1
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Bramwell G, Schultz AG, Jennings G, Nini UN, Vanbeek C, Biro PA, Beckmann C, Dujon AM, Thomas F, Sherman CDH, Ujvari B. The effect of mitochondrial recombination on fertilization success in blue mussels. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169491. [PMID: 38154641 DOI: 10.1016/j.scitotenv.2023.169491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/12/2023] [Accepted: 12/17/2023] [Indexed: 12/30/2023]
Abstract
The presence of doubly uniparental inheritance (DUI) in bivalves represents a unique mode of mitochondrial transmission, whereby paternal (male-transmitted M-type) and maternal (female-transmitted F-type) haplotypes are transmitted to offspring separately. Male embryos retain both haplotypes, but the M-type is selectively removed from females. Due to the presence of heteroplasmy in males, mtDNA can recombine resulting in a 'masculinized' haplotype referred to as Mf-type. While mtDNA recombination is usually rare, it has been recorded in multiple mussel species across the Northern Hemisphere. Given that mitochondria are the powerhouse of the cell, different mtDNA haplotypes may have different selective advantages under diverse environmental conditions. This may be particularly important for sperm fitness and fertilization success. In this study we aimed to i) determine the presence, prevalence of the Mf-type in Australian blue mussels (Mytilus sp.) and ii) investigate the effect of Mf-mtDNA on sperm performance (a fitness correlate). We found a high prevalence of recombined mtDNA (≈35 %) located within the control region of the mitochondrial genome, which occurred only in specimens that contained Southern Hemisphere mtDNA. The presence of two female mitotypes were identified in the studied mussels, one likely originating from the Northern Hemisphere, and the other either representing the endemic M. planulatus species or introduced genotypes from the Southern Hemisphere. Despite having recombination events present in a third of the studied population, analysis of sperm performance indicated no difference in fertilization success related to mitotype.
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Affiliation(s)
- Georgina Bramwell
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia
| | - Aaron G Schultz
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia
| | - Geordie Jennings
- Queenscliff Marine Research Facility and Shellfish Hatchery, Victorian Fisheries Australia, Queenscliff, VIC, Australia
| | - Urmi Nishat Nini
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia
| | - Caitlin Vanbeek
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia
| | - Peter A Biro
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia
| | - Christa Beckmann
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia; School of Science, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia; Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Antoine M Dujon
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia; CREEC, MIVEGEC, UMR IRD 224-CNRS 5290-Université de Montpellier, Montpellier, France
| | - Frédéric Thomas
- CREEC, MIVEGEC, UMR IRD 224-CNRS 5290-Université de Montpellier, Montpellier, France
| | - Craig D H Sherman
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia; Queenscliff Marine Research Facility and Shellfish Hatchery, Victorian Fisheries Australia, Queenscliff, VIC, Australia
| | - Beata Ujvari
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia.
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2
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Kong H, Sokolova IM. Oxidative phosphorylation rather than glycolysis is the primary energy source for sperm motility in the mussels Mytilus edulis. Comp Biochem Physiol B Biochem Mol Biol 2024; 270:110909. [PMID: 37898360 DOI: 10.1016/j.cbpb.2023.110909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 10/30/2023]
Abstract
Broadcast-spawning marine mussels rely on high sperm motility for successful fertilization in the dynamic seawater environment. Mitochondria are typically considered the primary source of ATP generation via oxidative phosphorylation (OXPHOS); however, the ATP generation pathways of mussel sperm have not been fully characterized. To better understand the importance of both OXPHOS and glycolysis for mussel sperm function, we conducted experiments inhibiting these pathways in sperm from Mytilus edulis. Our results indicate that oligomycin, an inhibitor of the mitochondrial ATP synthase, immediately decreased sperm motility rate, velocity, and ATP content, while 2-deoxy-d-glucose, a glycolysis inhibitor, had no effect. The OXPHOS inhibitor rotenone also partially reduced sperm motility rate and velocity. Interestingly, no evidence was found for the inhibitors' effects on the content of energy-rich compounds (lipids, carbohydrates, and proteins) in the mussels' sperm, indicating only modest energy demand to fuel sperm motility. Based on these findings, we conclude that OXPHOS is the primary energy source for sperm motility in marine mussels. Our study sheds light on the intricacies of mussel sperm physiology and highlights the importance of understanding the energy requirements for successful fertilization in broadcast-spawning marine invertebrates.
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Affiliation(s)
- Hui Kong
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany
| | - Inna M Sokolova
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany; Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, Rostock, Germany.
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3
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Smith CH, Mejia-Trujillo R, Breton S, Pinto BJ, Kirkpatrick M, Havird JC. Mitonuclear Sex Determination? Empirical Evidence from Bivalves. Mol Biol Evol 2023; 40:msad240. [PMID: 37935058 PMCID: PMC10653589 DOI: 10.1093/molbev/msad240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/04/2023] [Accepted: 10/26/2023] [Indexed: 11/09/2023] Open
Abstract
Genetic elements encoded in nuclear DNA determine the sex of an individual in many animals. In certain bivalve lineages that possess doubly uniparental inheritance (DUI), mitochondrial DNA (mtDNA) has been hypothesized to contribute to sex determination. In these cases, females transmit a female mtDNA to all offspring, while male mtDNA (M mtDNA) is transmitted only from fathers to sons. Because M mtDNA is inherited in the same way as Y chromosomes, it has been hypothesized that mtDNA may be responsible for sex determination. However, the role of mitochondrial and nuclear genes in sex determination has yet to be validated in DUI bivalves. In this study, we used DNA, RNA, and mitochondrial short noncoding RNA (sncRNA) sequencing to explore the role of mitochondrial and nuclear elements in the sexual development pathway of the freshwater mussel Potamilus streckersoni (Bivalvia: Unionida). We found that the M mtDNA sheds a sncRNA partially within a male-specific mitochondrial gene that targets a pathway hypothesized to be involved in female development and mitophagy. RNA-seq confirmed the gene target was significantly upregulated in females, supporting a direct role of mitochondrial sncRNAs in gene silencing. These findings support the hypothesis that M mtDNA inhibits female development. Genome-wide patterns of genetic differentiation and heterozygosity did not support a nuclear sex-determining region, although we cannot reject that nuclear factors are involved with sex determination. Our results provide further evidence that mitochondrial loci contribute to diverse, nonrespiratory functions and additional insights into an unorthodox sex-determining system.
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Affiliation(s)
- Chase H Smith
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | | | - Sophie Breton
- Department of Biological Sciences, University of Montreal, Montreal, Canada
| | - Brendan J Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, USA
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, USA
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Justin C Havird
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
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4
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Liu X, Sigwart JD, Sun J. Phylogenomic analyses shed light on the relationships of chiton superfamilies and shell-eye evolution. MARINE LIFE SCIENCE & TECHNOLOGY 2023; 5:525-537. [PMID: 38045544 PMCID: PMC10689665 DOI: 10.1007/s42995-023-00207-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 11/01/2023] [Indexed: 12/05/2023]
Abstract
Mollusca is the second-largest animal phylum with over 100,000 extant species representing eight classes. Across 1000 extant species in the class Polyplacophora, chitons have a relatively constrained morphology but with some notable deviations. Several genera possess "shell eyes", i.e., true eyes with a lens and retina that are embedded within the dorsal shells. The phylogeny of the major chiton clades is mostly well established, in a set of superfamily-level and higher level taxa supported by various approaches, including morphological studies, multiple gene markers, mitogenome-phylogeny, and phylotranscriptomic approaches. However, one critical lineage has remained unclear, namely Schizochiton which was controversially suggested as being the potential independent origin of chiton shell eyes. Here, with the draft genome sequencing of Schizochiton incisus (superfamily Schizochitonoidea) plus assemblies of transcriptome data from other polyplacophorans, we present phylogenetic reconstructions using both mitochondrial genomes and phylogenomic approaches with multiple methods. We found that phylogenetic trees from mitogenomic data are inconsistent, reflecting larger scale confounding factors in molluscan mitogenomes. However, a consistent and robust topology was generated with protein-coding genes using different models and methods. Our results support Schizochitonoidea as the sister group to other Chitonoidea in Chitonina, in agreement with the established classification. Combined with evidence from fossils, our phylogenetic results suggest that the earliest origin of shell eyes is in Schizochitonoidea, and that these structures were also gained secondarily in other genera in Chitonoidea. Our results have generated a holistic review of the internal relationship within Polyplacophora, and a better understanding of the evolution of Polyplacophora.
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Affiliation(s)
- Xu Liu
- Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003 China
- Laoshan Laboratory, Qingdao, 266237 China
| | - Julia D. Sigwart
- Department of Marine Zoology, Senckenberg Research Institute and Natural History Museum Frankfurt, 60325 Frankfurt Am Main, Germany
| | - Jin Sun
- Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, 266003 China
- Laoshan Laboratory, Qingdao, 266237 China
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5
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Debelli A, Kienzle L, Khorami HH, Angers A, Breton S. Validation of the male-specific ORF of the paternally-transmitted mtDNA in Mytilus edulis as a protein-coding gene. Gene 2023; 879:147586. [PMID: 37356740 DOI: 10.1016/j.gene.2023.147586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/14/2023] [Accepted: 06/20/2023] [Indexed: 06/27/2023]
Abstract
There appears to be an additional set of sex-specific mtDNA-encoded proteins in bivalve species with doubly uniparental mitochondrial inheritance that may be involved in the transmission of the female and male mitogenomes. In the marine mussel Mytilus edulis, the translation of the female-specific open reading frame (F-ORF) was demonstrated but the translation of the male-specific ORF (M-ORF) remains to be shown. Here we validate the male-specific ORF of the paternal mitogenome in M. edulis as a protein-coding gene. The M-ORF protein was detected only in male gonads and localized in sperm mitochondria and acrosome, suggesting that it is involved in a key sperm function in Mytilus edulis.
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Affiliation(s)
- Alizée Debelli
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Laura Kienzle
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Hajar Hosseini Khorami
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Annie Angers
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Sophie Breton
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada.
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6
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Smith CH, Mejia-Trujillo R, Breton S, Pinto BJ, Kirkpatrick M, Havird JC. Mitonuclear sex determination? Empirical evidence from bivalves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.05.547839. [PMID: 37461691 PMCID: PMC10349986 DOI: 10.1101/2023.07.05.547839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
Genetic elements encoded in nuclear DNA determine the sex of an individual in many animals. In bivalves, however, mitochondrial DNA (mtDNA) has been hypothesized to contribute to sex determination in lineages that possess doubly uniparental inheritance (DUI). In these cases, females transmit a female mtDNA (F mtDNA) to all offspring, while male mtDNA (M mtDNA) is transmitted only from fathers to sons. Because M mtDNA is inherited in the same way as Y chromosomes, it has been hypothesized that mtDNA may be responsible for sex determination. However, the role of mitochondrial and nuclear genes in sex determination has yet to be validated in DUI bivalves. In this study, we used DNA, RNA, and mitochondrial short non-coding RNA (sncRNA) sequencing to explore the role of mitochondrial and nuclear elements in the sexual development pathway of the freshwater mussel Potamilus streckersoni (Bivalvia: Unionida). We found that the M mtDNA shed a sncRNA partially within a male-specific mitochondrial gene that targeted pathways hypothesized to be involved in female development and mitophagy. RNA-seq confirmed the gene target was significantly upregulated in females, supporting a direct role of mitochondrial sncRNAs in gene silencing. These findings support the hypothesis that M mtDNA inhibits female development. Genome-wide patterns of genetic differentiation and heterozygosity did not support a nuclear sex determining region, although we cannot reject that nuclear factors are involved with sex determination. Our results provide further evidence that mitochondrial loci contribute to diverse, non-respiratory functions and provide a first glimpse into an unorthodox sex determining system.
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Affiliation(s)
- Chase H. Smith
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | | | - Sophie Breton
- Department of Biological Sciences, University of Montreal, Montreal, Canada
| | - Brendan J. Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ USA
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ USA
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI USA
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Justin C. Havird
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
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7
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Smith CH, Pinto BJ, Kirkpatrick M, Hillis DM, Pfeiffer JM, Havird JC. A tale of two paths: The evolution of mitochondrial recombination in bivalves with doubly uniparental inheritance. J Hered 2023; 114:199-206. [PMID: 36897956 PMCID: PMC10212130 DOI: 10.1093/jhered/esad004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 01/19/2023] [Indexed: 03/12/2023] Open
Abstract
In most animals, mitochondrial DNA is strictly maternally inherited and non-recombining. One exception to this pattern is called doubly uniparental inheritance (DUI), a phenomenon involving the independent transmission of female and male mitochondrial genomes. DUI is known only from the molluskan class Bivalvia. The phylogenetic distribution of male-transmitted mitochondrial DNA (M mtDNA) in bivalves is consistent with several evolutionary scenarios, including multiple independent gains, losses, and varying degrees of recombination with female-transmitted mitochondrial DNA (F mtDNA). In this study, we use phylogenetic methods to test M mtDNA origination hypotheses and infer the prevalence of mitochondrial recombination in bivalves with DUI. Phylogenetic modeling using site concordance factors supported a single origin of M mtDNA in bivalves coupled with recombination acting over long evolutionary timescales. Ongoing mitochondrial recombination is present in Mytilida and Venerida, which results in a pattern of concerted evolution of F mtDNA and M mtDNA. Mitochondrial recombination could be favored to offset the deleterious effects of asexual inheritance and maintain mitonuclear compatibility across tissues. Cardiida and Unionida have gone without recent recombination, possibly due to an extension of the COX2 gene in male mitochondrial DNA. The loss of recombination could be connected to the role of M mtDNA in sex determination or sexual development. Our results support that recombination events may occur throughout the mitochondrial genomes of DUI species. Future investigations may reveal more complex patterns of inheritance of recombinants, which could explain the retention of signal for a single origination of M mtDNA in protein-coding genes.
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Affiliation(s)
- Chase H Smith
- Department of Integrative Biology, University of Texas, Austin, TX, United States
| | - Brendan J Pinto
- Center for Evolutionary Medicine & Public Health, Arizona State University, Tempe, AZ, United States
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, United States
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas, Austin, TX, United States
| | - David M Hillis
- Department of Integrative Biology, University of Texas, Austin, TX, United States
| | - John M Pfeiffer
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, United States
- Department of Integrative Biology, University of Texas, Austin, TX, United States
| | - Justin C Havird
- Department of Integrative Biology, University of Texas, Austin, TX, United States
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8
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Martínez M, Harms L, Abele D, Held C. Mitochondrial Heteroplasmy and PCR Amplification Bias Lead to Wrong Species Delimitation with High Confidence in the South American and Antarctic Marine Bivalve Aequiyoldia eightsii Species Complex. Genes (Basel) 2023; 14:genes14040935. [PMID: 37107693 PMCID: PMC10138075 DOI: 10.3390/genes14040935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/29/2023] Open
Abstract
The species delimitation of the marine bivalve species complex Aequiyoldia eightsii in South America and Antarctica is complicated by mitochondrial heteroplasmy and amplification bias in molecular barcoding. In this study, we compare different data sources (mitochondrial cytochrome c oxidase subunit I (COI) sequences; nuclear and mitochondrial SNPs). Whilst all the data suggest that populations on either side of the Drake Passage belong to different species, the picture is less clear within Antarctic populations, which harbor three distinct mitochondrial lineages (p-dist ≈ 6%) that coexist in populations and in a subset of individuals with heteroplasmy. Standard barcoding procedures lead to amplification bias favoring either haplotype unpredictably and thus overestimate the species richness with high confidence. However, nuclear SNPs show no differentiation akin to the trans-Drake comparison, suggesting that the Antarctic populations represent a single species. Their distinct haplotypes likely evolved during periods of temporary allopatry, whereas recombination eroded similar differentiation patterns in the nuclear genome after secondary contact. Our study highlights the importance of using multiple data sources and careful quality control measures to avoid bias and increase the accuracy of molecular species delimitation. We recommend an active search for mitochondrial heteroplasmy and haplotype-specific primers for amplification in DNA-barcoding studies.
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Affiliation(s)
- Mariano Martínez
- Functional Ecology, Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, 27570 Bremerhaven, Germany
- Oceanografía y Ecología Marina, Instituto de Ecología y Ciencias Ambientales, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay
| | - Lars Harms
- Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, 27570 Bremerhaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Ammerländer Herrstrasse 231, 26129 Oldenburg, Germany
| | - Doris Abele
- Functional Ecology, Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Christoph Held
- Functional Ecology, Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, 27570 Bremerhaven, Germany
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9
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Mito-nuclear coevolution and phylogenetic artifacts: the case of bivalve mollusks. Sci Rep 2022; 12:11040. [PMID: 35773462 PMCID: PMC9247169 DOI: 10.1038/s41598-022-15076-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 06/17/2022] [Indexed: 11/08/2022] Open
Abstract
Mito-nuclear phylogenetic discordance in Bivalvia is well known. In particular, the monophyly of Amarsipobranchia (Heterodonta + Pteriomorphia), retrieved from mitochondrial markers, contrasts with the monophyly of Heteroconchia (Heterodonta + Palaeoheterodonta), retrieved from nuclear markers. However, since oxidative phosphorylation nuclear markers support the Amarsipobranchia hypothesis instead of the Heteroconchia one, interacting subunits of the mitochondrial complexes ought to share the same phylogenetic signal notwithstanding the genomic source, which is different from the signal obtained from other nuclear markers. This may be a clue of coevolution between nuclear and mitochondrial genes. In this work we inferred the phylogenetic signal from mitochondrial and nuclear oxidative phosphorylation markers exploiting different phylogenetic approaches and added two more datasets for comparison: genes of the glycolytic pathway and genes related to the biogenesis of regulative small noncoding RNAs. All trees inferred from mitochondrial and nuclear subunits of the mitochondrial complexes support the monophyly of Amarsipobranchia, regardless of the phylogenetic pipeline. However, not every single marker agrees with this topology: this is clearly visible in nuclear subunits that do not directly interact with the mitochondrial counterparts. Overall, our data support the hypothesis of a coevolution between nuclear and mitochondrial genes for the oxidative phosphorylation. Moreover, we suggest a relationship between mitochondrial topology and different nucleotide composition between clades, which could be associated to the highly variable gene arrangement in Bivalvia.
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10
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Tassé M, Choquette T, Angers A, Stewart DT, Pante E, Breton S. The longest mitochondrial protein in metazoans is encoded by the male-transmitted mitogenome of the bivalve Scrobicularia plana. Biol Lett 2022; 18:20220122. [PMID: 35673874 PMCID: PMC9174706 DOI: 10.1098/rsbl.2022.0122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Cytochrome c oxidase subunit II (COX2) is one of the three mitochondrially encoded proteins of the complex IV of the respiratory chain that catalyses the reduction of oxygen to water. The cox2 gene spans about 690 base pairs in most animal species and produces a protein composed of approximately 230 amino acids. We discovered an extreme departure from this pattern in the male-transmitted mitogenome of the bivalve Scrobicularia plana with doubly uniparental inheritance (DUI) of mitochondrial DNA (mtDNA), which possesses an important in-frame insertion of approximately 4.8 kb in its cox2 gene. This feature—an enlarged male cox2 gene—is found in many species with DUI; the COX2 protein can be up to 420 amino acids long. Through RT-PCRs, immunoassays and comparative genetics, the evolution and functionality of this insertion in S. plana were characterized. The in-frame insertion is conserved among individuals from different populations and bears the signature of purifying selection seemingly indicating maintenance of functionality. Its transcription and translation were confirmed: this gene produces a polypeptide of 1892 amino acids, making it the largest metazoan COX2 protein known to date. We hypothesize that these extreme modifications in the COX2 protein affect the metabolism of mitochondria containing the male-transmitted mtDNA in Scrobicularia plana.
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Affiliation(s)
- Mélanie Tassé
- Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
| | - Thierry Choquette
- Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
| | - Annie Angers
- Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
| | | | - Eric Pante
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France
| | - Sophie Breton
- Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
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11
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Baeza JA, García-De León FJ. Are we there yet? Benchmarking low-coverage nanopore long-read sequencing for the assembling of mitochondrial genomes using the vulnerable silky shark Carcharhinus falciformis. BMC Genomics 2022; 23:320. [PMID: 35459089 PMCID: PMC9027416 DOI: 10.1186/s12864-022-08482-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 03/18/2022] [Indexed: 12/28/2022] Open
Abstract
Background Whole mitochondrial genomes are quickly becoming markers of choice for the exploration of within-species genealogical and among-species phylogenetic relationships. Most often, ‘primer walking’ or ‘long PCR’ strategies plus Sanger sequencing or low-pass whole genome sequencing using Illumina short reads are used for the assembling of mitochondrial chromosomes. In this study, we first confirmed that mitochondrial genomes can be sequenced from long reads using nanopore sequencing data exclusively. Next, we examined the accuracy of the long-reads assembled mitochondrial chromosomes when comparing them to a ‘gold’ standard reference mitochondrial chromosome assembled using Illumina short-reads sequencing. Results Using a specialized bioinformatics tool, we first produced a short-reads mitochondrial genome assembly for the silky shark C. falciformis with an average base coverage of 9.8x. The complete mitochondrial genome of C. falciformis was 16,705 bp in length and 934 bp shorter than a previously assembled genome (17,639 bp in length) that used bioinformatics tools not specialized for the assembly of mitochondrial chromosomes. Next, low-pass whole genome sequencing using a MinION ONT pocket-sized platform plus customized de-novo and reference-based workflows assembled and circularized a highly accurate mitochondrial genome in the silky shark Carcharhinus falciformis. Indels at the flanks of homopolymer regions explained most of the dissimilarities observed between the ‘gold’ standard reference mitochondrial genome (assembled using Illumina short reads) and each of the long-reads mitochondrial genome assemblies. Although not completely accurate, mitophylogenomics and barcoding analyses (using entire mitogenomes and the D-Loop/Control Region, respectively) suggest that long-reads assembled mitochondrial genomes are reliable for identifying a sequenced individual, such as C. falciformis, and separating the same individual from others belonging to closely related congeneric species. Conclusions This study confirms that mitochondrial genomes can be sequenced from long-reads nanopore sequencing data exclusively. With further development, nanopore technology can be used to quickly test in situ mislabeling in the shark fin fishing industry and thus, improve surveillance protocols, law enforcement, and the regulation of this fishery. This study will also assist with the transferring of high-throughput sequencing technology to middle- and low-income countries so that international scientists can explore population genomics in sharks using inclusive research strategies. Lastly, we recommend assembling mitochondrial genomes using specialized assemblers instead of other assemblers developed for bacterial and/or nuclear genomes.
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Affiliation(s)
- J Antonio Baeza
- Department of Biological Sciences, 132 Long Hall, Clemson University, Clemson, SC, 29634, USA. .,Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Fort Pierce, Florida, 34949, USA. .,Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281, Coquimbo, Chile.
| | - F J García-De León
- Laboratorio de Genética para la Conservación, Centro de Investigaciones Biológicas del Noroeste, S.C., La Paz, Baja California Sur, Mexico
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12
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Breton S, Stewart DT, Brémaud J, Havird JC, Smith CH, Hoeh WR. Did doubly uniparental inheritance (DUI) of mtDNA originate as a cytoplasmic male sterility (CMS) system? Bioessays 2022; 44:e2100283. [PMID: 35170770 PMCID: PMC9083018 DOI: 10.1002/bies.202100283] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/26/2022] [Accepted: 01/31/2022] [Indexed: 01/10/2023]
Abstract
Animal and plant species exhibit an astonishing diversity of sexual systems, including environmental and genetic determinants of sex, with the latter including genetic material in the mitochondrial genome. In several hermaphroditic plants for example, sex is determined by an interaction between mitochondrial cytoplasmic male sterility (CMS) genes and nuclear restorer genes. Specifically, CMS involves aberrant mitochondrial genes that prevent pollen development and specific nuclear genes that restore it, leading to a mixture of female (male-sterile) and hermaphroditic individuals in the population (gynodioecy). Such a mitochondrial-nuclear sex determination system is thought to be rare outside plants. Here, we present one possible case of CMS in animals. We hypothesize that the only exception to the strict maternal mtDNA inheritance in animals, the doubly uniparental inheritance (DUI) system in bivalves, might have originated as a mitochondrial-nuclear sex-determination system. We document and explore similarities that exist between DUI and CMS, and we propose various ways to test our hypothesis.
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Affiliation(s)
- Sophie Breton
- Département des sciences biologiques, Université de Montréal, Montréal, Québec, Canada
| | - Donald T Stewart
- Department of Biology, Acadia University, Wolfville, Nova Scotia, Canada
| | - Julie Brémaud
- Département des sciences biologiques, Université de Montréal, Montréal, Québec, Canada
| | - Justin C Havird
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Chase H Smith
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Walter R Hoeh
- Department of Biological Sciences, Kent State University, Kent, Ohio, USA
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13
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McCartney MA, Auch B, Kono T, Mallez S, Zhang Y, Obille A, Becker A, Abrahante JE, Garbe J, Badalamenti JP, Herman A, Mangelson H, Liachko I, Sullivan S, Sone ED, Koren S, Silverstein KAT, Beckman KB, Gohl DM. The genome of the zebra mussel, Dreissena polymorpha: a resource for comparative genomics, invasion genetics, and biocontrol. G3 (BETHESDA, MD.) 2022; 12:6460334. [PMID: 34897429 PMCID: PMC9210306 DOI: 10.1093/g3journal/jkab423] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/02/2021] [Indexed: 02/07/2023]
Abstract
The zebra mussel, Dreissena polymorpha, continues to spread from its native range in Eurasia to Europe and North America, causing billions of dollars in damage and dramatically altering invaded aquatic ecosystems. Despite these impacts, there are few genomic resources for Dreissena or related bivalves. Although the D. polymorpha genome is highly repetitive, we have used a combination of long-read sequencing and Hi-C-based scaffolding to generate a high-quality chromosome-scale genome assembly. Through comparative analysis and transcriptomics experiments, we have gained insights into processes that likely control the invasive success of zebra mussels, including shell formation, synthesis of byssal threads, and thermal tolerance. We identified multiple intact steamer-like elements, a retrotransposon that has been linked to transmissible cancer in marine clams. We also found that D. polymorpha have an unusual 67 kb mitochondrial genome containing numerous tandem repeats, making it the largest observed in Eumetazoa. Together these findings create a rich resource for invasive species research and control efforts.
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Affiliation(s)
- Michael A McCartney
- Department of Fisheries, Wildlife and Conservation Biology, Minnesota Aquatic Invasive Species Research Center, University of Minnesota, St. Paul, MN 55108, USA
| | - Benjamin Auch
- University of Minnesota Genomics Center, Minneapolis, MN 55455, USA
| | - Thomas Kono
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sophie Mallez
- Department of Fisheries, Wildlife and Conservation Biology, Minnesota Aquatic Invasive Species Research Center, University of Minnesota, St. Paul, MN 55108, USA
| | - Ying Zhang
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Angelico Obille
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Aaron Becker
- University of Minnesota Genomics Center, Minneapolis, MN 55455, USA
| | - Juan E Abrahante
- University of Minnesota Informatics Institute, Minneapolis, MN 55455, USA
| | - John Garbe
- University of Minnesota Genomics Center, Minneapolis, MN 55455, USA
| | | | - Adam Herman
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | | - Eli D Sone
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada.,Department of Materials Science & Engineering, University of Toronto, Toronto, ON M5S 3E4 Canada.,Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada
| | - Sergey Koren
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, Bethesda, MD 20892, USA
| | - Kevin A T Silverstein
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | | | - Daryl M Gohl
- University of Minnesota Genomics Center, Minneapolis, MN 55455, USA.,Department of Genetics, Cell Biology, and Developmental Biology, University of Minnesota, Minneapolis, MN 55455, USA
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14
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Dégletagne C, Abele D, Glöckner G, Alric B, Gruber H, Held C. Presence of male mitochondria in somatic tissues and their functional importance at the whole animal level in the marine bivalve Arctica islandica. Commun Biol 2021; 4:1104. [PMID: 34545198 PMCID: PMC8452683 DOI: 10.1038/s42003-021-02593-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 08/16/2021] [Indexed: 02/08/2023] Open
Abstract
Metazoans normally possess a single lineage of mitochondria inherited from the mother (♀-type mitochondria) while paternal mitochondria are absent or eliminated in fertilized eggs. In doubly uniparental inheritance (DUI), which is specific to the bivalve clade including the ocean quahog, Arctica islandica, ♂-type mitochondria are retained in male gonads and, in a few species, small proportions of ♂-type mitochondria co-exist with ♀-type in somatic tissues. To the best of our knowledge, we report, for the first time in metazoan, the natural occurrence of male and female individuals with exclusively ♂-type mitochondria in somatic tissues of the bivalve A. islandica. Mitochondrial genomes differ by ~5.5% at DNA sequence level. Exclusive presence of ♂-type mitochondria affects mitochondrial complexes partially encoded by mitochondrial genes and leads to a sharp drop in respiratory capacity. Through a combination of whole mitochondrial genome sequencing and molecular assays (gene presence and expression), we demonstrate that 1) 11% of individuals of an Icelandic population appear homoplasmic for ♂-type mitochondria in somatic tissues, 2) ♂-type mitochondrial genes are transcribed and 3) individuals with ♂-type mitochondria in somatic cells lose 30% of their wild-type respiratory capacity. This mitochondrial pattern in A. islandica is a special case of DUI, highlighted in individuals from both sexes with functional consequences at cellular and conceivably whole animal level.
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Affiliation(s)
- Cyril Dégletagne
- grid.10894.340000 0001 1033 7684Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany ,grid.7849.20000 0001 2150 7757Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, Villeurbanne, France
| | - Doris Abele
- grid.10894.340000 0001 1033 7684Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
| | - Gernot Glöckner
- grid.6190.e0000 0000 8580 3777Institute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - Benjamin Alric
- grid.7849.20000 0001 2150 7757Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, Villeurbanne, France
| | - Heike Gruber
- grid.419520.b0000 0001 2222 4708Max Planck Institute for Evolutionary Biology, Department of Evolutionary Theory, Plön, Germany
| | - Christoph Held
- grid.10894.340000 0001 1033 7684Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
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15
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Piccinini G, Iannello M, Puccio G, Plazzi F, Havird JC, Ghiselli F. Mitonuclear Coevolution, but not Nuclear Compensation, Drives Evolution of OXPHOS Complexes in Bivalves. Mol Biol Evol 2021; 38:2597-2614. [PMID: 33616640 PMCID: PMC8136519 DOI: 10.1093/molbev/msab054] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In Metazoa, four out of five complexes involved in oxidative phosphorylation (OXPHOS) are formed by subunits encoded by both the mitochondrial (mtDNA) and nuclear (nuDNA) genomes, leading to the expectation of mitonuclear coevolution. Previous studies have supported coadaptation of mitochondria-encoded (mtOXPHOS) and nuclear-encoded OXPHOS (nuOXPHOS) subunits, often specifically interpreted with regard to the “nuclear compensation hypothesis,” a specific form of mitonuclear coevolution where nuclear genes compensate for deleterious mitochondrial mutations due to less efficient mitochondrial selection. In this study, we analyzed patterns of sequence evolution of 79 OXPHOS subunits in 31 bivalve species, a taxon showing extraordinary mtDNA variability and including species with “doubly uniparental” mtDNA inheritance. Our data showed strong and clear signals of mitonuclear coevolution. NuOXPHOS subunits had concordant topologies with mtOXPHOS subunits, contrary to previous phylogenies based on nuclear genes lacking mt interactions. Evolutionary rates between mt and nuOXPHOS subunits were also highly correlated compared with non-OXPHO-interacting nuclear genes. Nuclear subunits of chimeric OXPHOS complexes (I, III, IV, and V) also had higher dN/dS ratios than Complex II, which is formed exclusively by nuDNA-encoded subunits. However, we did not find evidence of nuclear compensation: mitochondria-encoded subunits showed similar dN/dS ratios compared with nuclear-encoded subunits, contrary to most previously studied bilaterian animals. Moreover, no site-specific signals of compensatory positive selection were detected in nuOXPHOS genes. Our analyses extend the evidence for mitonuclear coevolution to a new taxonomic group, but we propose a reconsideration of the nuclear compensation hypothesis.
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Affiliation(s)
- Giovanni Piccinini
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Mariangela Iannello
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Guglielmo Puccio
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Federico Plazzi
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Justin C Havird
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Fabrizio Ghiselli
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
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16
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Ghiselli F, Iannello M, Piccinini G, Milani L. Bivalve molluscs as model systems for studying mitochondrial biology. Integr Comp Biol 2021; 61:1699-1714. [PMID: 33944910 DOI: 10.1093/icb/icab057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The class Bivalvia is a highly successful and ancient taxon including ∼25,000 living species. During their long evolutionary history bivalves adapted to a wide range of physicochemical conditions, habitats, biological interactions, and feeding habits. Bivalves can have strikingly different size, and despite their apparently simple body plan, they evolved very different shell shapes, and complex anatomic structures. One of the most striking features of this class of animals is their peculiar mitochondrial biology: some bivalves have facultatively anaerobic mitochondria that allow them to survive prolonged periods of anoxia/hypoxia. Moreover, more than 100 species have now been reported showing the only known evolutionarily stable exception to the strictly maternal inheritance of mitochondria in animals, named doubly uniparental inheritance. Mitochondrial activity is fundamental to eukaryotic life, and thanks to their diversity and uncommon features, bivalves represent a great model system to expand our knowledge about mitochondrial biology, so far limited to a few species. We highlight recent works studying mitochondrial biology in bivalves at either genomic or physiological level. A link between these two approaches is still missing, and we believe that an integrated approach and collaborative relationships are the only possible ways to be successful in such endeavour.
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Affiliation(s)
- Fabrizio Ghiselli
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Italy
| | - Mariangela Iannello
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Italy
| | - Giovanni Piccinini
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Italy
| | - Liliana Milani
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Italy
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17
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Ghiselli F, Gomes-Dos-Santos A, Adema CM, Lopes-Lima M, Sharbrough J, Boore JL. Molluscan mitochondrial genomes break the rules. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200159. [PMID: 33813887 DOI: 10.1098/rstb.2020.0159] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The first animal mitochondrial genomes to be sequenced were of several vertebrates and model organisms, and the consistency of genomic features found has led to a 'textbook description'. However, a more broad phylogenetic sampling of complete animal mitochondrial genomes has found many cases where these features do not exist, and the phylum Mollusca is especially replete with these exceptions. The characterization of full mollusc mitogenomes required considerable effort involving challenging molecular biology, but has created an enormous catalogue of surprising deviations from that textbook description, including wide variation in size, radical genome rearrangements, gene duplications and losses, the introduction of novel genes, and a complex system of inheritance dubbed 'doubly uniparental inheritance'. Here, we review the extraordinary variation in architecture, molecular functioning and intergenerational transmission of molluscan mitochondrial genomes. Such features represent a great potential for the discovery of biological history, processes and functions that are novel for animal mitochondrial genomes. This provides a model system for studying the evolution and the manifold roles that mitochondria play in organismal physiology, and many ways that the study of mitochondrial genomes are useful for phylogeny and population biology. This article is part of the Theo Murphy meeting issue 'Molluscan genomics: broad insights and future directions for a neglected phylum'.
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Affiliation(s)
- Fabrizio Ghiselli
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Italy
| | - André Gomes-Dos-Santos
- CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, and Department of Biology, Faculty of Sciences, University of Porto, Portugal
| | - Coen M Adema
- Center for Evolutionary and Theoretical Immunology, Department of Biology, University of New Mexico, Albuquerque, USA
| | - Manuel Lopes-Lima
- CIBIO/InBIO, Research Center in Biodiversity and Genetic Resources, University of Porto, Vairão, Portugal
| | - Joel Sharbrough
- Department of Biology, Colorado State University, Fort Collins, USA
| | - Jeffrey L Boore
- Providence St Joseph Health and the Institute for Systems Biology, Seattle, USA
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18
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Mortz M, Levivier A, Lartillot N, Dufresne F, Blier PU. Long-Lived Species of Bivalves Exhibit Low MT-DNA Substitution Rates. Front Mol Biosci 2021; 8:626042. [PMID: 33791336 PMCID: PMC8005583 DOI: 10.3389/fmolb.2021.626042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 01/28/2021] [Indexed: 01/21/2023] Open
Abstract
Bivalves represent valuable taxonomic group for aging studies given their wide variation in longevity (from 1–2 to >500 years). It is well known that aging is associated to the maintenance of Reactive Oxygen Species homeostasis and that mitochondria phenotype and genotype dysfunctions accumulation is a hallmark of these processes. Previous studies have shown that mitochondrial DNA mutation rates are linked to lifespan in vertebrate species, but no study has explored this in invertebrates. To this end, we performed a Bayesian Phylogenetic Covariance model of evolution analysis using 12 mitochondrial protein-coding genes of 76 bivalve species. Three life history traits (maximum longevity, generation time and mean temperature tolerance) were tested against 1) synonymous substitution rates (dS), 2) conservative amino acid replacement rates (Kc) and 3) ratios of radical over conservative amino acid replacement rates (Kr/Kc). Our results confirm the already known correlation between longevity and generation time and show, for the first time in an invertebrate class, a significant negative correlation between dS and longevity. This correlation was not as strong when generation time and mean temperature tolerance variations were also considered in our model (marginal correlation), suggesting a confounding effect of these traits on the relationship between longevity and mtDNA substitution rate. By confirming the negative correlation between dS and longevity previously documented in birds and mammals, our results provide support for a general pattern in substitution rates.
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Affiliation(s)
- Mathieu Mortz
- Institut Des Sciences De La Mer De Rimouski, Université Du Québec à Rimouski, Rimouski, QC, Canada
| | - Aurore Levivier
- Institut Des Sciences De La Mer De Rimouski, Université Du Québec à Rimouski, Rimouski, QC, Canada
| | - Nicolas Lartillot
- Laboratoire De Biométrie et Biologie Evolutive, UMR CNRS, Université Lyon 1, Villeurbanne, France
| | - France Dufresne
- Laboratoire D'écologie Moléculaire, Département De Biologie, Université Du Québec à Rimouski, Rimouski, QC, Canada.,Laboratoire De Physiologie Intégrative Et Evolutive, Département De Biologie, Université Du Québec à Rimouski, Rimouski, QC, Canada
| | - Pierre U Blier
- Laboratoire De Physiologie Intégrative Et Evolutive, Département De Biologie, Université Du Québec à Rimouski, Rimouski, QC, Canada
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19
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Klapper R, Schröder U. Verification of authenticity: A rapid identification method for commercial scallop species through multiplex real-time PCR. Food Control 2021. [DOI: 10.1016/j.foodcont.2020.107574] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Baeza JA. Yes, we can use it: a formal test on the accuracy of low-pass nanopore long-read sequencing for mitophylogenomics and barcoding research using the Caribbean spiny lobster Panulirus argus. BMC Genomics 2020; 21:882. [PMID: 33297960 PMCID: PMC7726883 DOI: 10.1186/s12864-020-07292-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 11/28/2020] [Indexed: 12/11/2022] Open
Abstract
Background Whole mitogenomes or short fragments (i.e., 300–700 bp of the cox1 gene) are the markers of choice for revealing within- and among-species genealogies. Protocols for sequencing and assembling mitogenomes include ‘primer walking’ or ‘long PCR’ followed by Sanger sequencing or Illumina short-read low-coverage whole genome (LC-WGS) sequencing with or without prior enrichment of mitochondrial DNA. The aforementioned strategies assemble complete and accurate mitochondrial genomes but are time consuming and/or expensive. In this study, I first tested whether mitogenomes can be sequenced from long-read nanopore sequencing data exclusively. Second, I explored the accuracy of the long-read assembled genomes by comparing them to a ‘gold’ standard reference mitogenome retrieved from the same individual using Illumina sequencing. Third and lastly, I tested if the long-read assemblies are useful for mitophylogenomics and barcoding research. To accomplish these goals, I used the Caribbean spiny lobster Panulirus argus, an ecologically relevant species in shallow water coral reefs and target of the most lucrative fishery in the greater Caribbean region. Results LC-WGS using a MinION ONT device and various de-novo and reference-based assembly pipelines retrieved a complete and highly accurate mitogenome for the Caribbean spiny lobster Panulirus argus. Discordance between each of the long-read assemblies and the reference mitogenome was mostly due to indels at the flanks of homopolymer regions. Although not ‘perfect’, phylogenetic analyses using entire mitogenomes or a fragment of the cox1 gene demonstrated that mitogenomes assembled using long reads reliably identify the sequenced specimen as belonging to P. argus and distinguish it from other related species in the same genus, family, and superorder. Conclusions This study serves as a proof-of-concept for the future implementation of in-situ surveillance protocols using the MinION to detect mislabeling in P. argus across its supply chain. Mislabeling detection will improve fishery management in this overexploited lobster. This study will additionally aid in decreasing costs for exploring meta-population connectivity in the Caribbean spiny lobster and will aid with the transfer of genomics technology to low-income countries.
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Affiliation(s)
- J Antonio Baeza
- Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC, 29634, USA. .,Smithsonian Marine Station at Fort Pierce, 701 Seaway Drive, Fort Pierce, Florida, 34949, USA. .,Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile.
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21
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Xu R, Pan L, Yang Y, Zhou Y. Characterizing transcriptome in female scallop Chlamys farreri provides new insights into the molecular mechanisms of reproductive regulation during ovarian development and spawn. Gene 2020; 758:144967. [PMID: 32707299 DOI: 10.1016/j.gene.2020.144967] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 07/06/2020] [Accepted: 07/17/2020] [Indexed: 10/23/2022]
Abstract
Bivalve mollusks are descendants of an early-Cambrian lineage and have successfully evolved unique strategies for reproduction. Nonetheless, the molecular mechanisms underlying reproductive regulation in mollusks remain to be elucidated. In this study, transcriptomes of ovary at four reproductive stages in female Chlamys farreri were characterized by RNA-Seq. Regarding signaling pathways, ECM-receptor interaction pathway, mTOR signaling pathway, Fanconi anemia pathway, FoxO signaling pathway, Wnt signaling pathway and Hedgehog signaling pathway were enriched during ovarian development processes. In addition, pathways related to energy metabolism such as Nitrogen metabolism and Arachidonic acid metabolism were enriched at spawn stage. Interestingly, Neuroactive ligand-receptor interaction was significantly enriched involved in ovarian development and spawn, and indicated the potential functions of nervous system on reproductive regulation in C. farreri. What's more, this study identified and characterized fourteen genes involved in "sex hormones synthesis and regulation", "ovarian development and spawn" and "maternal immunity" during the four reproductive stages in C. farreri. We determined that CYP17 uniquely affected gamete release by influencing the physiological balance among the steroid hormones and showed that receptors of the 5-HT and GABA neurotransmitters were tightly associated with ovarian maturation. Furthermore, to the best of our knowledge, this is the first study to report the maternal effect gene Zar1 in bivalve mollusks, likewise the maternal immunity genes displayed coordinated and cooperative expression during reproductive periods, which strengthened the environmental adaptation mechanisms of bivalves. Taken together, this study provides the first dynamic transcriptomic analysis of C. farreri at four key reproductive stages, which will assist in revealing the molecular mechanisms underlying bivalves on reproductive regulation in ovarian development and spawn.
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Affiliation(s)
- Ruiyi Xu
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
| | - Luqing Pan
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China.
| | - Yingying Yang
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
| | - Yueyao Zhou
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
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22
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Lubośny M, Przyłucka A, Śmietanka B, Burzyński A. Semimytilus algosus: first known hermaphroditic mussel with doubly uniparental inheritance of mitochondrial DNA. Sci Rep 2020; 10:11256. [PMID: 32647112 PMCID: PMC7347871 DOI: 10.1038/s41598-020-67976-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 06/11/2020] [Indexed: 11/08/2022] Open
Abstract
Doubly uniparental inheritance (DUI) of mitochondrial DNA is a rare phenomenon occurring in some freshwater and marine bivalves and is usually characterized by the mitochondrial heteroplasmy of male individuals. Previous research on freshwater Unionida mussels showed that hermaphroditic species do not have DUI even if their closest gonochoristic counterparts do. No records showing DUI in a hermaphrodite have ever been reported. Here we show for the first time that the hermaphroditic mussel Semimytilus algosus (Mytilida), very likely has DUI, based on the complete sequences of both mitochondrial DNAs and the distribution of mtDNA types between male and female gonads. The two mitogenomes show considerable divergence (34.7%). The presumably paternal M type mitogenome dominated the male gonads of most studied mussels, while remaining at very low or undetectable levels in the female gonads of the same individuals. If indeed DUI can function in the context of simultaneous hermaphroditism, a change of paradigm regarding its involvement in sex determination is needed. It is apparently associated with gonadal differentiation rather than with sex determination in bivalves.
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Affiliation(s)
- Marek Lubośny
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland.
| | - Aleksandra Przyłucka
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
| | - Beata Śmietanka
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
| | - Artur Burzyński
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
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23
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Morphology of Mitochondria in Syncytial Annelid Female Germ-Line Cyst Visualized by Serial Block-Face SEM. Int J Cell Biol 2020; 2020:7483467. [PMID: 32395131 PMCID: PMC7199535 DOI: 10.1155/2020/7483467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/11/2019] [Accepted: 08/04/2019] [Indexed: 11/23/2022] Open
Abstract
Mitochondria change their morphology and distribution depending on the metabolism and functional state of a cell. Here, we analyzed the mitochondria and selected structures in female germ-line cysts in a representative of clitellate annelids – the white worm Enchytraeus albidus in which each germ cell has one cytoplasmic bridge that connects it to a common cytoplasmic mass. Using serial block-face scanning electron microscopy (SBEM), we prepared three-dimensional ultrastructural reconstructions of the entire selected compartments of a cyst at the advanced stage of oogenesis, i.e. the nurse cell, cytophore, and cytoplasmic bridges of all 16 cells (15 nurse cells and oocyte). We revealed extensive mitochondrial networks in the nurse cells, cytophore and mitochondria that pass through the cytoplasmic bridges, which indicates that a mitochondrial network can extend throughout the entire cyst. The dynamic hyperfusion state was suggested for such mitochondrial aggregations. We measured the mitochondria distribution and revealed their polarized distribution in the nurse cells and more abundant accumulation within the cytophore compared to the nurse cell. A close association of mitochondrial networks with dispersed nuage material, which seems to be the structural equivalent of a Balbiani body, not described in clitellate annelids so far, was also revealed.
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24
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Soroka M. Doubly uniparental inheritance of mitochondrial DNA in freshwater mussels: History and status of the European species. J ZOOL SYST EVOL RES 2020. [DOI: 10.1111/jzs.12381] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Sato K, Kano Y, Setiamarga DHE, Watanabe HK, Sasaki T. Molecular phylogeny of protobranch bivalves and systematic implications of their shell microstructure. ZOOL SCR 2020. [DOI: 10.1111/zsc.12419] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Kei Sato
- Waseda University Tokyo Japan
- The University Museum The University of Tokyo Tokyo Japan
| | - Yasunori Kano
- Atmosphere and Ocean Research Institute The University of Tokyo Chiba Japan
| | - Davin H. E. Setiamarga
- The University Museum The University of Tokyo Tokyo Japan
- National Institute of Technology Wakayama College Gobo Japan
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Klucnika A, Ma H. A battle for transmission: the cooperative and selfish animal mitochondrial genomes. Open Biol 2020; 9:180267. [PMID: 30890027 PMCID: PMC6451365 DOI: 10.1098/rsob.180267] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The mitochondrial genome is an evolutionarily persistent and cooperative component of metazoan cells that contributes to energy production and many other cellular processes. Despite sharing the same host as the nuclear genome, the multi-copy mitochondrial DNA (mtDNA) follows very different rules of replication and transmission, which translate into differences in the patterns of selection. On one hand, mtDNA is dependent on the host for its transmission, so selections would favour genomes that boost organismal fitness. On the other hand, genetic heterogeneity within an individual allows different mitochondrial genomes to compete for transmission. This intra-organismal competition could select for the best replicator, which does not necessarily give the fittest organisms, resulting in mito-nuclear conflict. In this review, we discuss the recent advances in our understanding of the mechanisms and opposing forces governing mtDNA transmission and selection in bilaterians, and what the implications of these are for mtDNA evolution and mitochondrial replacement therapy.
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Affiliation(s)
- Anna Klucnika
- 1 Wellcome Trust/Cancer Research UK Gurdon Institute , Tennis Court Road, Cambridge CB2 1QN , UK.,2 Department of Genetics, University of Cambridge , Downing Street, Cambridge CB2 3EH , UK
| | - Hansong Ma
- 1 Wellcome Trust/Cancer Research UK Gurdon Institute , Tennis Court Road, Cambridge CB2 1QN , UK.,2 Department of Genetics, University of Cambridge , Downing Street, Cambridge CB2 3EH , UK
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Passamonti M, Plazzi F. Doubly Uniparental Inheritance and beyond: The contribution of the Manila clamRuditapes philippinarum. J ZOOL SYST EVOL RES 2020. [DOI: 10.1111/jzs.12371] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Marco Passamonti
- Department of Biological, Geological, and Environmental Sciences University of Bologna Bologna Italy
| | - Federico Plazzi
- Department of Biological, Geological, and Environmental Sciences University of Bologna Bologna Italy
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Capt C, Bouvet K, Guerra D, Robicheau BM, Stewart DT, Pante E, Breton S. Unorthodox features in two venerid bivalves with doubly uniparental inheritance of mitochondria. Sci Rep 2020; 10:1087. [PMID: 31974502 PMCID: PMC6978325 DOI: 10.1038/s41598-020-57975-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/09/2020] [Indexed: 12/02/2022] Open
Abstract
In animals, strictly maternal inheritance (SMI) of mitochondria is the rule, but one exception (doubly uniparental inheritance or DUI), marked by the transmission of sex-specific mitogenomes, has been reported in bivalves. Associated with DUI is a frequent modification of the mitochondrial cox2 gene, as well as additional sex-specific mitochondrial genes not involved in oxidative phosphorylation. With the exception of freshwater mussels (for 3 families of the order Unionida), these DUI-associated features have only been shown in few species [within Mytilidae (order Mytilida) and Veneridae (order Venerida)] because of the few complete sex-specific mitogenomes published for these orders. Here, we present the complete sex-specific mtDNAs of two recently-discovered DUI species in two families of the order Venerida, Scrobicularia plana (Semelidae) and Limecola balthica (Tellinidae). These species display the largest differences in genome size between sex-specific mitotypes in DUI species (>10 kb), as well as the highest mtDNA divergences (sometimes reaching >50%). An important in-frame insertion (>3.5 kb) in the male cox2 gene is partly responsible for the differences in genome size. The S. plana cox2 gene is the largest reported so far in the Kingdom Animalia. The mitogenomes may be carrying sex-specific genes, indicating that general mitochondrial features are shared among DUI species.
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Affiliation(s)
- Charlotte Capt
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada.
| | - Karim Bouvet
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada
| | - Davide Guerra
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada
| | | | - Donald T Stewart
- Department of Biology, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | - Eric Pante
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000, La Rochelle, France
| | - Sophie Breton
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada.
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Lubośny M, Śmietanka B, Przyłucka A, Burzyński A. Highly divergent mitogenomes ofGeukensia demissa(Bivalvia, Mytilidae) with extreme AT content. J ZOOL SYST EVOL RES 2020. [DOI: 10.1111/jzs.12354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marek Lubośny
- Department of Genetics and Marine Biotechnology Institute of Oceanology Polish Academy of Sciences Sopot Poland
| | - Beata Śmietanka
- Department of Genetics and Marine Biotechnology Institute of Oceanology Polish Academy of Sciences Sopot Poland
| | - Aleksandra Przyłucka
- Department of Genetics and Marine Biotechnology Institute of Oceanology Polish Academy of Sciences Sopot Poland
| | - Artur Burzyński
- Department of Genetics and Marine Biotechnology Institute of Oceanology Polish Academy of Sciences Sopot Poland
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Guerra D, Lopes-Lima M, Froufe E, Gan HM, Ondina P, Amaro R, Klunzinger MW, Callil C, Prié V, Bogan AE, Stewart DT, Breton S. Variability of mitochondrial ORFans hints at possible differences in the system of doubly uniparental inheritance of mitochondria among families of freshwater mussels (Bivalvia: Unionida). BMC Evol Biol 2019; 19:229. [PMID: 31856711 PMCID: PMC6923999 DOI: 10.1186/s12862-019-1554-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 12/09/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Supernumerary ORFan genes (i.e., open reading frames without obvious homology to other genes) are present in the mitochondrial genomes of gonochoric freshwater mussels (Bivalvia: Unionida) showing doubly uniparental inheritance (DUI) of mitochondria. DUI is a system in which distinct female-transmitted and male-transmitted mitotypes coexist in a single species. In families Unionidae and Margaritiferidae, the transition from dioecy to hermaphroditism and the loss of DUI appear to be linked, and this event seems to affect the integrity of the ORFan genes. These observations led to the hypothesis that the ORFans have a role in DUI and/or sex determination. Complete mitochondrial genome sequences are however scarce for most families of freshwater mussels, therefore hindering a clear localization of DUI in the various lineages and a comprehensive understanding of the influence of the ORFans on DUI and sexual systems. Therefore, we sequenced and characterized eleven new mitogenomes from poorly sampled freshwater mussel families to gather information on the evolution and variability of the ORFan genes and their protein products. RESULTS We obtained ten complete plus one almost complete mitogenome sequence from ten representative species (gonochoric and hermaphroditic) of families Margaritiferidae, Hyriidae, Mulleriidae, and Iridinidae. ORFan genes are present only in DUI species from Margaritiferidae and Hyriidae, while non-DUI species from Hyriidae, Iridinidae, and Mulleriidae lack them completely, independently of their sexual system. Comparisons among the proteins translated from the newly characterized ORFans and already known ones provide evidence of conserved structures, as well as family-specific features. CONCLUSIONS The ORFan proteins show a comparable organization of secondary structures among different families of freshwater mussels, which supports a conserved physiological role, but also have distinctive family-specific features. Given this latter observation and the fact that the ORFans can be either highly mutated or completely absent in species that secondarily lost DUI depending on their respective family, we hypothesize that some aspects of the connection among ORFans, sexual systems, and DUI may differ in the various lineages of unionids.
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Affiliation(s)
- Davide Guerra
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC Canada
| | - Manuel Lopes-Lima
- CIBIO/InBIO - Research Center in Biodiversity and Genetic Resources, University of Porto, Campus Agrário de Vairão, Vairão, Portugal
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Matosinhos, Portugal
| | - Elsa Froufe
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Matosinhos, Portugal
| | - Han Ming Gan
- Deakin Genomics Centre, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria Australia
| | - Paz Ondina
- Departamento de Zooloxía, Xenética e Antropoloxía Física, Facultade de Veterinaria, Universidade de Santiago de Compostela, Campus de Lugo, Lugo, Spain
| | - Rafaela Amaro
- Departamento de Zooloxía, Xenética e Antropoloxía Física, Facultade de Veterinaria, Universidade de Santiago de Compostela, Campus de Lugo, Lugo, Spain
| | - Michael W. Klunzinger
- BWG Environmental, Brisbane, QLD Australia
- Mollusca, Department of Aquatic Zoology, Western Australian Museum, Welshpool, WA Australia
- School of Veterinary and Biological Sciences, Murdoch University, Perth, WA Australia
| | - Claudia Callil
- ECOBiv - Ecology and Conservation of Bivalves Research Group, Department of Biology and Zoology, Federal University of Mato Grosso, Cuiabá, MT Brazil
| | - Vincent Prié
- Institut Systématique Evolution Biodiversité ISYEB - Muséum National d’Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, France
| | | | | | - Sophie Breton
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC Canada
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Capt C, Renaut S, Stewart DT, Johnson NA, Breton S. Putative Mitochondrial Sex Determination in the Bivalvia: Insights From a Hybrid Transcriptome Assembly in Freshwater Mussels. Front Genet 2019; 10:840. [PMID: 31572447 PMCID: PMC6754070 DOI: 10.3389/fgene.2019.00840] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/13/2019] [Indexed: 11/13/2022] Open
Abstract
Bivalves exhibit an astonishing diversity of sexual systems, with genetic and environmental determinants of sex, and possibly the only example of mitochondrial genes influencing sex determination pathways in animals. In contrast to all other animal species in which strict maternal inheritance (SMI) of mitochondria is the rule, bivalves possess a system known as doubly uniparental inheritance (DUI) of mitochondria in which maternal and paternal mitochondria (and their corresponding female-transmitted or F mtDNA and male-transmitted or M mtDNA genomes) are transmitted within a species. Species with DUI also possess sex-associated mtDNA-encoded proteins (in addition to the typical set of 13), which have been hypothesized to play a role in sex determination. In this study, we analyzed the sex-biased transcriptome in gonads of two closely-related freshwater mussel species with different reproductive and mitochondrial transmission modes: the gonochoric, DUI species, Utterbackia peninsularis, and the hermaphroditic, SMI species, Utterbackia imbecillis. Through comparative analysis with other DUI and non-DUI bivalve transcriptomes already available, we identify common male and female-specific genes, as well as SMI and DUI-related genes, that are probably involved in sex determination and mitochondrial inheritance in this animal group. Our results contribute to the understanding of what could be the first animal sex determination system involving the mitochondrial genome.
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Affiliation(s)
- Charlotte Capt
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada
| | - Sébastien Renaut
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada.,Centre de la Science de la Biodiversité du Québec, Université de Montréal, Montréal, QC, Canada
| | | | - Nathan A Johnson
- Wetland and Aquatic Research Center, U.S. Geological Survey, Gainesville, FL, United States
| | - Sophie Breton
- Department of Biological Sciences, Université de Montréal, Montréal, QC, Canada
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Sun CH, Liu DW, Huang YL, Zhou YW, Hou SL, Lu CH. Genetic diversity analysis of Peking gecko ( Gekko swinhonis) in mid-Eastern China based on mitochondrial COI and Cyt b gene sequences. MITOCHONDRIAL DNA PART B-RESOURCES 2019; 4:2156-2158. [PMID: 33365452 PMCID: PMC7687432 DOI: 10.1080/23802359.2019.1623724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
To understand the genetic diversity of Peking gecko (Gekko swinhonis) populations in its endemic region, 60 individuals were sampled from Lushan, Qi, and Linying counties in Henan Province, China. Through PCR amplification and Sanger sequencing, 120 sequences with lengths of 652 bp (COI) and 739 bp (Cyt b) were obtained, and nine haplotypes were detected for each gene. Overall, results indicated that Peking gecko populations in China have high genetic diversity and significant genetic differentiation. This study provides necessary scientific basis for the protection of Peking gecko germplasm resources.
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Affiliation(s)
- Cheng-He Sun
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
| | - Da-Wei Liu
- Forest Police Identification Center of National Forestry Administration, Nanjing Forest Police College, Nanjing, China
| | - Ya-Lin Huang
- Forest Police Identification Center of National Forestry Administration, Nanjing Forest Police College, Nanjing, China
| | - Yong-Wu Zhou
- Forest Police Identification Center of National Forestry Administration, Nanjing Forest Police College, Nanjing, China
| | - Sen-Lin Hou
- Forest Police Identification Center of National Forestry Administration, Nanjing Forest Police College, Nanjing, China
| | - Chang-Hu Lu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
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Andrade M, De Marchi L, Pretti C, Chiellini F, Morelli A, Figueira E, Rocha RJM, Soares AMVM, Freitas R. The impacts of warming on the toxicity of carbon nanotubes in mussels. MARINE ENVIRONMENTAL RESEARCH 2019; 145:11-21. [PMID: 30771907 DOI: 10.1016/j.marenvres.2019.01.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 01/25/2019] [Accepted: 01/27/2019] [Indexed: 06/09/2023]
Abstract
With the increased production and research on nanoparticles, the presence of carbon nanotubes (CNTs) in aquatic systems is very likely to increase. Although it has been shown that CNTs may cause toxicity in marine organisms, to our knowledge, the possible impacts under global temperature increase is still unknown. For this reason, biochemical and physiological impacts induced in Mytilus galloprovincialis due to the presence of functionalized multi-walled CNTs (f-MWCNTs) and increased temperature were investigated in the present study. The mussels exposed to increased temperature alone presented higher metabolic capacity and expenditure of glycogen as an energy resource to fuel up defense mechanisms and thus preventing oxidative damage. Contrarily, organisms exposed to f-MWCNTs alone seemed not stressed enough to demonstrate differences in the metabolism capacity. Furthermore, f-MWCNTs seemed not able to significantly activate their antioxidant and biotransformation enzymes, which in turn may led to oxidative damage in the cells especially when organisms were exposed to a warmer temperature. In fact, at higher temperature, the antioxidant response of organisms exposed to f-MWCNTs was not effective and oxidative damage levels were observed. Nevertheless, no additive or synergetic effects were observed when mussels were exposed to both stressors simultaneously.
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Affiliation(s)
- Madalena Andrade
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Lucia De Marchi
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Carlo Pretti
- Department of Veterinary Sciences, University of Pisa, San Piero a Grado, Pisa, 56122, Italy; Consortium for the Interuniversity Center of Marine Biology and Applied Ecology, Livorno, Italy
| | - Federica Chiellini
- Department of Chemistry and Industrial Chemistry, University of Pisa, Udr INSTM Pisa, Pisa, 56126, Italy
| | - Andrea Morelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, Udr INSTM Pisa, Pisa, 56126, Italy
| | - Etelvina Figueira
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Rui J M Rocha
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Amadeu M V M Soares
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Rosa Freitas
- Department of Biology & Center for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193, Aveiro, Portugal.
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Patnaik BB, Chung JM, Hwang HJ, Sang MK, Park JE, Min HR, Cho HC, Dewangan N, Baliarsingh S, Kang SW, Park SY, Jo YH, Park HS, Kim WJ, Han YS, Lee JS, Lee YS. Transcriptome analysis of air-breathing land slug, Incilaria fruhstorferi reveals functional insights into growth, immunity, and reproduction. BMC Genomics 2019; 20:154. [PMID: 30808280 PMCID: PMC6390351 DOI: 10.1186/s12864-019-5526-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 02/11/2019] [Indexed: 01/27/2023] Open
Abstract
Background Incilaria (= Meghimatium) fruhstorferi is an air-breathing land slug found in restricted habitats of Japan, Taiwan and selected provinces of South Korea (Jeju, Chuncheon, Busan, and Deokjeokdo). The species is on a decline due to depletion of forest cover, predation by natural enemies, and collection. To facilitate the conservation of the species, it is important to decide on a number of traits related to growth, immunity and reproduction addressing fitness advantage of the species. Results The visceral mass transcriptome of I. fruhstorferi was enabled using the Illumina HiSeq 4000 sequencing platform. According to BUSCO (Benchmarking Universal Single-Copy Orthologs) method, the transcriptome was considered complete with 91.8% of ortholog genes present (Single: 70.7%; Duplicated: 21.1%). A total of 96.79% of the raw read sequences were processed as clean reads. TransDecoder identified 197,271 contigs that contained candidate-coding regions. Of a total of 50,230 unigenes, 34,470 (68.62% of the total unigenes) annotated to homologous proteins in the Protostome database (PANM-DB). The GO term and KEGG pathway analysis indicated genes involved in metabolism, phosphatidylinositol signalling system, aminobenzoate degradation, and T-cell receptor signalling pathway. Many genes associated with molluscan innate immunity were categorized under pathogen recognition receptor, TLR signalling pathway, MyD88 dependent pathway, endogenous ligands, immune effectors, antimicrobial peptides, apoptosis, and adaptation-related. The reproduction-associated unigenes showed homology to protein fem-1, spermatogenesis-associated protein, sperm associated antigen, and testis expressed sequences, among others. In addition, we identified key growth-related genes categorized under somatotrophic axis, muscle growth, chitinases and collagens. A total of 4822 Simple Sequence Repeats (SSRs) were also identified from the unigene sequences of I. fruhstorferi. Conclusions This is the first available genomic information for non-model land slug, I. fruhstorferi focusing on genes related to growth, immunity, and reproduction, with additional focus on microsatellites and repeating elements. The transcriptome provides access to greater number of traits of unknown relevance in the species that could be exploited for in-depth analyses of evolutionary plasticity and making informed choices during conservation planning. This would be appropriate for understanding the dynamics of the species on a priority basis considering the ecological, health, and social benefits. Electronic supplementary material The online version of this article (10.1186/s12864-019-5526-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bharat Bhusan Patnaik
- School of Biotech Sciences, Trident Academy of Creative Technology (TACT), F2-B, Chandaka Industrial Estate, Chandrasekharpur, Bhubaneswar, Odisha, 751024, India
| | - Jong Min Chung
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Hee Ju Hwang
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Min Kyu Sang
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Jie Eun Park
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Hye Rin Min
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Hang Chul Cho
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Neha Dewangan
- School of Biotech Sciences, Trident Academy of Creative Technology (TACT), F2-B, Chandaka Industrial Estate, Chandrasekharpur, Bhubaneswar, Odisha, 751024, India
| | - Snigdha Baliarsingh
- School of Biotech Sciences, Trident Academy of Creative Technology (TACT), F2-B, Chandaka Industrial Estate, Chandrasekharpur, Bhubaneswar, Odisha, 751024, India
| | - Se Won Kang
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 181, Ipsin-gil, Jungeup-si, Jeollabuk-do, 56212, South Korea
| | - So Young Park
- Nakdonggang National Institute of Biological Resources, Biodiversity Conservation and Change Research Division, 137, Donam-2-gil, Sangju-si, Gyeongsangbuk-do, 37242, South Korea
| | - Yong Hun Jo
- College of Agriculture and Life Science, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Hong Seog Park
- Research Institute, GnC BIO Co., LTD, 621-6 Banseok-dong, Yuseong-gu, Daejeon, 34069, Republic of Korea
| | - Wan Jong Kim
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Yeon Soo Han
- College of Agriculture and Life Science, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Jun Sang Lee
- Institute of Basic Science, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea
| | - Yong Seok Lee
- Department of Life Science and Biotechnology, College of Natural Sciences, Soonchunhyang University, 22 Soonchunhyangro, Shinchang-myeon, Asan, Chungchungnam-do, 31538, South Korea.
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Chacón GM, Arias‐Pérez A, Freire R, Martínez L, Nóvoa S, Naveira H, Insua A. Evidence of doubly uniparental inheritance of the mitochondrial
DNA
in
Polititapes rhomboides
(Bivalvia, Veneridae): Evolutionary and population genetic analysis of F and M mitotypes. J ZOOL SYST EVOL RES 2019. [DOI: 10.1111/jzs.12267] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Ginna M. Chacón
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
| | - Alberto Arias‐Pérez
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
| | - Ruth Freire
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
| | - Luisa Martínez
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
| | - Susana Nóvoa
- Centro de Cultivos Marinos de Ribadeo‐CIMAXunta de Galicia Ribadeo (Lugo) Spain
| | - Horacio Naveira
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
| | - Ana Insua
- Departamento de Bioloxía‐Facultade de Ciencias and Centro de Investigacións Científicas Avanzadas (CICA)Universidade da Coruña A Coruña Spain
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Doubly Uniparental Inheritance of mtDNA: An Unappreciated Defiance of a General Rule. ADVANCES IN ANATOMY EMBRYOLOGY AND CELL BIOLOGY 2019; 231:25-49. [DOI: 10.1007/102_2018_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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37
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Chase EE, Robicheau BM, Hoeh WR, Harris JL, Stewart DT, Breton S. The complete male-type mitochondrial genomes of the Fatmucket, Lampsilis siliquoidea, and the endangered Arkansas Fatmucket, Lampsilis powellii. Mitochondrial DNA B Resour 2019. [DOI: 10.1080/23802359.2018.1536459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- E. E. Chase
- Department of Biology, Acadia University, Wolfville, Canada
| | - B. M. Robicheau
- Department of Biology, Life Science Centre, Dalhousie University, Halifax, Canada
| | - W. R. Hoeh
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - J. L. Harris
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR, USA
| | - D. T. Stewart
- Department of Biology, Acadia University, Wolfville, Canada
| | - S. Breton
- Department of Biological Sciences, University of Montreal, Montreal, Canada
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Plazzi F, Passamonti M. Footprints of unconventional mitochondrial inheritance in bivalve phylogeny: Signatures of positive selection on clades with doubly uniparental inheritance. J ZOOL SYST EVOL RES 2018. [DOI: 10.1111/jzs.12253] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Federico Plazzi
- Department of Biological, Geological and Environmental Sciences University of Bologna Bologna Italy
| | - Marco Passamonti
- Department of Biological, Geological and Environmental Sciences University of Bologna Bologna Italy
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Towards a global phylogeny of freshwater mussels (Bivalvia: Unionida): Species delimitation of Chinese taxa, mitochondrial phylogenomics, and diversification patterns. Mol Phylogenet Evol 2018; 130:45-59. [PMID: 30308278 DOI: 10.1016/j.ympev.2018.09.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 08/18/2018] [Accepted: 09/28/2018] [Indexed: 11/20/2022]
Abstract
The Yangtze River Basin in China is one of the global hotspots of freshwater mussel (order Unionida) diversity with 68 nominal species. Few studies have tested the validity of these nominal species. Some taxa from the Yangtze unionid fauna have not been adequately examined using molecular data and well-positioned phylogenetically with respect to the global Unionida. We evaluated species boundaries of Chinese freshwater mussels, and disentangled their phylogenetic relationships within the context of the global freshwater mussels based on the multi-locus data and complete mitochondrial genomes. Moreover, we produced the time-calibrated phylogeny of Unionida and explored patterns of diversification. COI barcode data suggested the existence of 41 phylogenetic distinct species from our sampled 40 nominal taxa inhabiting the middle and lower reaches of the Yangtze River. Maximum likelihood and Bayesian inference analyses on three loci (COI, 16S, and 28S) and complete mitochondrial genomes showed that the subfamily Unioninae sensu stricto was paraphyletic, and the subfamily Anodontinae should be subsumed under Unioninae. In addition, we described two new tribes (Aculamprotulini tribe nov. and Lepidodesmini tribe nov.) in the subfamily Unioninae and one new genus (Parvasolenaiagen. nov.) in the subfamily Gonideinae. Molecular dating analysis suggested freshwater mussels diversified at 346.1 Mya (HPD = 286.6-409.9). The global diversification rate for Unionida was estimated to be 0.025 species/Myr. Our study found only a single well-supported rate shift in Unionida diversification, occurring at the base of the subfamily Ambleminae. The evolution of active host-attraction may have triggered the burst of speciation in Ambleminae, and the environment and geography of the Mississippi River Basin likely sustained this radiation.
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40
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Śmietanka B, Lubośny M, Przyłucka A, Gérard K, Burzyński A. Mitogenomics of Perumytilus purpuratus (Bivalvia: Mytilidae) and its implications for doubly uniparental inheritance of mitochondria. PeerJ 2018; 6:e5593. [PMID: 30245933 PMCID: PMC6149501 DOI: 10.7717/peerj.5593] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 08/14/2018] [Indexed: 12/29/2022] Open
Abstract
Animal mitochondria are usually inherited through the maternal lineage. The exceptional system allowing fathers to transmit their mitochondria to the offspring exists in some bivalves. Its taxonomic spread is poorly understood and new mitogenomic data are needed to fill the gap. Here, we present for the first time the two divergent mitogenomes from Chilean mussel Perumytilus purpuratus. The existence of these sex-specific mitogenomes confirms that this species has the doubly uniparental inheritance (DUI) of mitochondria. The genetic distance between the two mitochondrial lineages in P. purpuratus is not only much bigger than in the Mytilus edulis species complex but also greater than the distance observed in Musculista senhousia, the only other DUI-positive member of the Mytilidae family for which both complete mitochondrial genomes were published to date. One additional, long ORF (open reading frame) is present exclusively in the maternal mitogenome of P. purpuratus. This ORF evolves under purifying selection, and will likely be a target for future DUI research.
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Affiliation(s)
- Beata Śmietanka
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
| | - Marek Lubośny
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
| | - Aleksandra Przyłucka
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
| | - Karin Gérard
- Centro de Investigacion Gaia-Antartica, Departamento de Recursos Naturales, Universidad de Magallanes, Punta Arenas, Chile.,Laboratorio de Ecosistemas Marinos Antárticos y Subantárticos, Universidad de Magallanes, Punta Arenas, Chile
| | - Artur Burzyński
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
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41
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Robicheau BM, Chase EE, Hoeh WR, Harris JL, Stewart DT, Breton S. Evaluating the utility of the female-specific mitochondrial f-orf gene for population genetic, phylogeographic and systematic studies in freshwater mussels (Bivalvia: Unionida). PeerJ 2018; 6:e5007. [PMID: 29915706 PMCID: PMC6004104 DOI: 10.7717/peerj.5007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 05/29/2018] [Indexed: 12/19/2022] Open
Abstract
Freshwater mussels (order: Unionida) represent one of the most critically imperilled groups of animals; consequently, there exists a need to establish a variety of molecular markers for population genetics and systematic studies in this group. Recently, two novel mitochondrial protein-coding genes were described in unionoids with doubly uniparental inheritance of mtDNA. These genes are the f-orf in female-transmitted mtDNA and the m-orf in male-transmitted mtDNA. In this study, whole F-type mitochondrial genome sequences of two morphologically similar Lampsilis spp. were compared to identify the most divergent protein-coding regions, including the f-orf gene, and evaluate its utility for population genetic and phylogeographic studies in the subfamily Ambleminae. We also tested whether the f-orf gene is phylogenetically informative at the species level. Our preliminary results indicated that the f-orf gene could represent a viable molecular marker for population- and species-level studies in freshwater mussels.
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Affiliation(s)
- Brent M Robicheau
- Department of Biology, Acadia University, Wolfville, Canada.,Current affiliation: Department of Biology, Life Science Centre, Dalhousie University, Halifax, Canada
| | - Emily E Chase
- Department of Biology, Acadia University, Wolfville, Canada
| | - Walter R Hoeh
- Department of Biological Sciences, Kent State University, Kent, United States of America
| | - John L Harris
- Department of Biological Sciences, Arkansas State University, Jonesboro, United States of America
| | | | - Sophie Breton
- Department of Biological Sciences, University of Montreal, Montreal, Canada
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42
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Stewart DT, Sinclair-Waters M, Rice A, Bunker RA, Robicheau BM, Breton S. Distribution and frequency of mitochondrial DNA polymorphisms in blue mussel ( Mytilus edulis) populations of southwestern Nova Scotia (Canada). CAN J ZOOL 2018. [DOI: 10.1139/cjz-2017-0212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Atlantic blue mussel (Mytilus edulis Linnaeus, 1758) exhibits doubly uniparental inheritance of mitochondrial (mt) DNA. Females are usually homoplasmic for a female-transmitted mt genome (the F type) and males are heteroplasmic for an F type and a male-transmitted mt genome (the M type). F types can undergo “role-reversal” events, resulting in new male-transmitted mtDNA genomes known as recently masculinized (RM) types that co-occur in populations with evolutionarily older standard-male (SM) types. Phylogenetic analyses have shown that RM types periodically replace SM types. It has also been shown that sperm with RM mtDNA have greater swimming velocity and more efficient components of the electron transport chain compared to sperm with SM mtDNA, thus leading to the hypothesis that RM sperm may have a selective advantage over SM sperm. The present study examines the distribution of RM and SM mitotypes in male M. edulis (n = 225) from 13 localities in southwestern Nova Scotia (Canada). The SM type was more common in all populations, with the proportion of RM types ranging from 0% to 24.1%. The highest proportion of RM types was observed in an aquaculture operation. Analyses of additional populations are required to evaluate the selective pressures affecting the geographic distribution of RM and SM mitotypes in M. edulis.
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Affiliation(s)
- Donald T. Stewart
- Department of Biology, Acadia University, Wolfville, NS B4P 2R6, Canada
| | | | - Alexandra Rice
- Department of Biology, Acadia University, Wolfville, NS B4P 2R6, Canada
| | - Ryan A. Bunker
- Department of Biology, Acadia University, Wolfville, NS B4P 2R6, Canada
| | | | - Sophie Breton
- Department of Biology, Acadia University, Wolfville, NS B4P 2R6, Canada
- Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada
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43
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Mikkelsen NT, Kocot KM, Halanych KM. Mitogenomics reveals phylogenetic relationships of caudofoveate aplacophoran molluscs. Mol Phylogenet Evol 2018; 127:429-436. [PMID: 29702218 DOI: 10.1016/j.ympev.2018.04.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 01/16/2018] [Accepted: 04/20/2018] [Indexed: 11/28/2022]
Abstract
The worm-shaped, shell-less aplacophoran molluscs Caudofoveata and Solenogastres have recently received attention as part of the clade Aculifera, but relationships within these two lineages are still largely unknown. Here, we use complete mitochondrial genomes to shed light on higher-level relationships within Caudofoveata. Mitochondrial genomes have been sequenced for many diverse molluscs, but only two mitochondrial genomes from aplacophoran molluscs (the caudofoveates Scutopus ventrolineatus and Chaetoderma nitidulum) are available to date. We sequenced and assembled complete or near complete mitochondrial genomes of five additional species of Caudofoveata (Falcidens acutargatus, Falcidens halanychi, Scutopus robustus, Psilodens balduri and Spathoderma clenchi) and one species of Solenogastres (Neomenia carinata) for comparison to available mitochondrial genomes of aculiferans. Comparison of mitochondrial gene order among different lineages revealed a highly conserved order of protein coding genes corresponding to the hypothesized ancestral gene order for Mollusca. Unique arrangements of tRNAs were found among lineages of aculiferan molluscs as well as among caudofoveate taxa. Phylogenetic analyses of amino acid sequences for the 13 protein-coding genes recovered a monophyletic Aplacophora. Within Caudofoveata, Chaetodermatidae, but not Limifossoridae, was recovered monophyletic. Taken together, our results suggest that mitochondrial genomes can serve as useful molecular markers for aculiferan phylogenetics, especially for more recent phylogenetic events.
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Affiliation(s)
- Nina T Mikkelsen
- University Museum of Bergen, University of Bergen, 5020 Bergen, Norway; Department of Biology, University of Bergen, 5020 Bergen, Norway.
| | - Kevin M Kocot
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA; Department of Biological Sciences and Alabama Museum of Natural History, The University of Alabama, Tuscaloosa, AL 35487, USA(1)
| | - Kenneth M Halanych
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
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44
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Ozawa G, Shimamura S, Takaki Y, Takishita K, Ikuta T, Barry JP, Maruyama T, Fujikura K, Yoshida T. Ancient Occasional Host Switching of Maternally Transmitted Bacterial Symbionts of Chemosynthetic Vesicomyid Clams. Genome Biol Evol 2018; 9:2226-2236. [PMID: 28922872 PMCID: PMC5604134 DOI: 10.1093/gbe/evx166] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2017] [Indexed: 11/22/2022] Open
Abstract
Vesicomyid clams in deep-sea chemosynthetic ecosystems harbor sulfur-oxidizing bacteria in their gill epithelial cells. These symbionts, which are vertically transmitted, are species-specific and thought to have cospeciated with their hosts. However, recent studies indicate incongruent phylogenies between some vesicomyid clams and their symbionts, suggesting that symbionts are horizontally transmitted. To more precisely understand the evolution of vesicomyid clams and their symbionts, we compared the evolution of vesicomyid clams and their symbionts through phylogenetic analyses using multi-gene data sets. Many clades in the phylogenetic trees of 13 host species (Abyssogena mariana, Ab. phaseoliformis, Akebiconcha kawamurai, Calyptogena fausta, C. laubieri, C. magnifica, C. nautilei, C. pacifica, Isorropodon fossajaponicum, Phreagena kilmeri, Ph. okutanii, Ph. soyoae, and Pliocardia stearnsii) and their symbionts were well resolved. Six of the 13 host-symbiont pairs (C. fausta, C. magnifica, C. pacifica, Ph. kilmeri, Ph. okutanii, and Ph. soyoae, and their respective symbionts) showed topological congruence. However, the remaining seven pairs (Ak. kawamurai, Ab mariana, Ab. phaseoliformis, C. laubieri, C. nautilei, I. fossajaponicum, and Pl. stearnsii and their corresponding symbionts) showed incongruent topologies, which were supported by the approximately unbiased and Bayes factor tests. Coevolution analyses indicated that six pairs cospeciated, whereas host switching events occurred in the remaining seven pairs. Markedly, multiple host switching events may have occurred in the lineages from the common ancestral symbiont of C. pacifica and C. fausta. Our phylogenetic and coevolution analyses provide additional evidence for host switching during the evolution of vesicomyids.
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Affiliation(s)
- Genki Ozawa
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan.,Department of Marine Biosciences, School of Marine Biosciences, Kitasato University, Minami-ku, Sagamihara, Kanagawa, Japan
| | - Shigeru Shimamura
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - Yoshihiro Takaki
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - Kiyotaka Takishita
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - Tetsuro Ikuta
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - James P Barry
- Monterey Bay Aquarium Research Institute, Moss Landing, Monterey, California
| | - Tadashi Maruyama
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - Katsunori Fujikura
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan
| | - Takao Yoshida
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Natsushima-cho, Yokosuka, Kanagawa, Japan.,Department of Marine Biosciences, School of Marine Biosciences, Kitasato University, Minami-ku, Sagamihara, Kanagawa, Japan
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45
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Punzi E, Milani L, Ghiselli F, Passamonti M. Lose it or keep it: (how bivalves can provide) insights into mitochondrial inheritance mechanisms. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2018; 330:41-51. [PMID: 29393570 DOI: 10.1002/jez.b.22788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/02/2017] [Accepted: 01/09/2018] [Indexed: 01/22/2023]
Abstract
The strictly maternal inheritance (SMI) is a pattern of mitochondrial inheritance observed across the whole animal kingdom. However, some interesting exceptions are known for the class Bivalvia, in which several species show an unusual pattern called doubly uniparental inheritance (DUI) whose outcome is a heteroplasmic pool of mtDNA in males. Even if DUI has been studied for long, its molecular basis has not been established yet. The aim of this work is to select classes of proteins known to be involved in the maintenance of SMI and to compare their features in two clam species differing for their mitochondrial inheritance mechanism, that is, the SMI species Ruditapes decussatus and the DUI species Ruditapes philippinarum. Data have been obtained from the transcriptomes of male and female ripe gonads of both species. Our analysis focused on nucleases and polymerases, ubiquitination and ubiquitin-like modifier pathways, and proteins involved in autophagy and mitophagy. For each protein group of interest, transcription bias (male or female), annotation, and mitochondrial targeting (when appropriate) were assessed. We did not find evidence supporting a role of nucleases/polymerases or autophagic machinery in the enforcement of SMI in R. decussatus. On the other hand, ubiquitinating enzymes with the expected features have been retrieved, providing us with two alternative testable models for mitochondrial inheritance mechanisms at the molecular level.
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Affiliation(s)
- Elisabetta Punzi
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Liliana Milani
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Fabrizio Ghiselli
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Marco Passamonti
- Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
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46
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Liu X, Cao Y, Xue T, Wu R, Zhou Y, Zhou C, Zanatta DT, Ouyang S, Wu X. Genetic structure and diversity of Nodularia douglasiae (Bivalvia: Unionida) from the middle and lower Yangtze River drainage. PLoS One 2017; 12:e0189737. [PMID: 29261733 PMCID: PMC5738091 DOI: 10.1371/journal.pone.0189737] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 11/30/2017] [Indexed: 11/19/2022] Open
Abstract
The Yangtze River drainage in China is among the most species rich rivers for freshwater mussels (order Unionida) on Earth with at least 68 species known. The freshwater mussels of the Yangtze River face a variety of threats with indications that species are declining in abundance and area of occupancy. This study represents the first analyses of the genetic structure and diversity for the common and widespread freshwater mussel Nodularia douglasiae based on microsatellite DNA genotypes and mitochondrial DNA sequences. Phylogenetic analysis a fragment of the COI mitochondrial gene indicated that N. douglasiae collected from across the middle and lower Yangtze River drainage are monophyletic with N. douglasiae from Japan, Russia, and South Korea. The results of the analysis of both the mtDNA and microsatellite datasets indicated that the seven collection locations of N. douglasiae in the middle and lower Yangtze River drainage showed high genetic diversity, significant genetic differentiation and genetic structure, and stable population dynamics over time. Moreover, we found that the connections among tributaries rivers and lakes in the Yangtze River drainage were important in maintaining gene flow among locations that N. douglasiae inhabits. An understanding of the genetic structure and diversity of a widespread species like N. douglasiae could be used as a surrogate to better understand the populations of other freshwater mussel species that are more rare in the Yangtze River drainage. At the same time, these results could provide a basis for the protection of genetic diversity and management of unionid mussels diversity and other aquatic organisms in the system.
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Affiliation(s)
- Xiongjun Liu
- Poyang Lake Key Laboratory of Environment and Resource Utilization (Nanchang University), Ministry of Education, Nanchang, People’s Republic of China
- School of Resource, Environment and Chemical Engineering, Nanchang University, Nanchang, People’s Republic of China
| | - Yanling Cao
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
| | - Taotao Xue
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
| | - Ruiwen Wu
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
| | - Yu Zhou
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
| | - Chunhua Zhou
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
| | - David T. Zanatta
- Central Michigan University, Institute for Great Lakes Research, Biology Department, Biosciences 2408, Mount Pleasant, MI, United States of America
- * E-mail: (DTZ); (SO); (XW)
| | - Shan Ouyang
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
- * E-mail: (DTZ); (SO); (XW)
| | - Xiaoping Wu
- Poyang Lake Key Laboratory of Environment and Resource Utilization (Nanchang University), Ministry of Education, Nanchang, People’s Republic of China
- School of Resource, Environment and Chemical Engineering, Nanchang University, Nanchang, People’s Republic of China
- School of Life Sciences, Nanchang University, Nanchang, People’s Republic of China
- * E-mail: (DTZ); (SO); (XW)
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47
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Coppola F, Almeida Â, Henriques B, Soares AMVM, Figueira E, Pereira E, Freitas R. Biochemical impacts of Hg in Mytilus galloprovincialis under present and predicted warming scenarios. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 601-602:1129-1138. [PMID: 28599369 DOI: 10.1016/j.scitotenv.2017.05.201] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 05/21/2017] [Accepted: 05/22/2017] [Indexed: 06/07/2023]
Abstract
The interest in the consequences of climate change on the physiological and biochemical functioning of marine organisms is increasing, but the indirect and interactive effects resulting from warming on bioconcentration and responsiveness to pollutants are still poorly explored, particularly in terms of cellular responses. The present study investigated the impacts of Hg in Mytilus galloprovincialis under control (17°C) and warming (21°C) conditions, assessing mussels Hg bioconcentration capacity, metabolic and oxidative status after 14 and 28days of exposure. Results obtained showed greater impacts in mussels exposed for 28days in comparison to 14days of exposure. Furthermore, our findings revealed that the increase in temperature from 17 to 21°C reduced the bioconcentration of Hg by M. galloprovincialis, which may explain higher mortality rates at 17°C in comparison to 21°C. Lower Hg concentration at 21°C in mussels tissue may result from valves closure for longer periods, identified by reduced energy reserves consumption at higher temperature, which in turn might also contributed to higher oxidative stress in organisms exposed to this condition. The highest LPO levels observed in mussels exposed to higher temperatures alone indicate that warming conditions will greatly affect M. galloprovincialis. Furthermore, the present study showed that the impacts induced by the combination of Hg and warming were similar to the ones caused by increased temperature acting alone, mainly due to increased antioxidant defenses in organisms under combined effects of Hg and warming, suggesting that warming was the factor that mostly contributed to oxidative stress in mussels. Although higher mortality was observed in individuals exposed to 17°C and Hg compared to organisms exposed to Hg at 21°C, the oxidative stress induced at higher temperature may generate negative consequences on mussels reproductive and feeding capacity, growth and, consequently, on population maintenance and dynamics.
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Affiliation(s)
- Francesca Coppola
- Biology Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Ângela Almeida
- Biology Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Bruno Henriques
- Chemistry Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal; CIIMAR, Interdisciplinary Centre of Marine and Environmental Research , Rua dos Bragas 289, 4050-123 Porto, Portugal
| | | | - Etelvina Figueira
- Biology Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Eduarda Pereira
- Chemistry Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Rosa Freitas
- Biology Department & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
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48
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Soroka M, Burzyński A. Hermaphroditic freshwater mussel Anodonta cygnea does not have supranumerary open reading frames in the mitogenome. Mitochondrial DNA B Resour 2017; 2:862-864. [PMID: 33474013 PMCID: PMC7800200 DOI: 10.1080/23802359.2017.1407705] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 11/17/2017] [Indexed: 11/10/2022] Open
Abstract
The complete mitogenome of Anodonta cygnea is 15,613 bp long. This compact, circular molecule contains the set of 37 genes, typical for invertebrate mitogenomes, in the same order and orientation as in maternally inherited genomes of other bivalves from the same subfamily. There are only two unassigned regions longer than 200 bp (266 bp and 274 bp) and no indication of any supranumerary open reading frames.
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Affiliation(s)
- Marianna Soroka
- Department of Genetics, Faculty of Biology, University of Szczecin, Szczecin, Poland
| | - Artur Burzyński
- Department of Genetics and Marine Biotechnology, Institute of Oceanology Polish Academy of Sciences, Sopot, Poland
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49
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Mioduchowska M, Kaczmarczyk A, Zając K, Zając T, Sell J. Gender-Associated Mitochondrial DNA Heteroplasmy in Somatic Tissues of the Endangered Freshwater Mussel Unio crassus (Bivalvia: Unionidae): Implications for Sex Identification and Phylogeographical Studies. ACTA ACUST UNITED AC 2017; 325:610-625. [PMID: 28102008 DOI: 10.1002/jez.2055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 10/11/2016] [Accepted: 10/24/2016] [Indexed: 11/11/2022]
Abstract
Some bivalve species possess two independent mitochondrial DNA lineages: maternally (F-type) and paternally (M-type) inherited. This phenomenon is called doubly uniparental inheritance. It is generally agreed that F-type mtDNA is typically present in female somatic and gonadal tissues as well as in male somatic tissues, whereas the M-type mtDNA occurs only in male germ line and gonadal tissue. In the present study, the mtDNA heteroplasmy (for both F and M genomes) in male somatic tissues of Unio crassus (Philipsson, 1788), species threatened with extinction, has been confirmed. Taking advantage from the presence of Mcox1 marker only in male somatic tissues, we developed a new method of sex identification in this endangered species, using nondestructive tissue sampling. Probability of correct sex identification was estimated at 97.5%. The present study is the first report on gender-associated mitochondrial DNA heteroplasmy in male somatic tissues of thick-shelled river mussel and first approach to U. crassus sex identification at molecular level. Our study also confirmed the utility of paternally inherited Mcox1 gene fragment as a complementary molecular tool for resolving phylogeographical relationships among populations of thick-shelled river mussel.
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Affiliation(s)
| | | | - Katarzyna Zając
- Institute of Nature Conservation, Polish Academy of Sciences, 31-120 Krakow, Poland
| | - Tadeusz Zając
- Institute of Nature Conservation, Polish Academy of Sciences, 31-120 Krakow, Poland
| | - Jerzy Sell
- Department of Genetics, University of Gdansk, 80-308 Gdansk, Poland
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50
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Sun S, Li Q, Kong L, Yu H. Multiple reversals of strand asymmetry in molluscs mitochondrial genomes, and consequences for phylogenetic inferences. Mol Phylogenet Evol 2017; 118:222-231. [PMID: 29038046 DOI: 10.1016/j.ympev.2017.10.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 10/08/2017] [Accepted: 10/12/2017] [Indexed: 01/05/2023]
Abstract
Strand asymmetry in nucleotide composition is a remarkable feature of animal mitochondrial genomes. The strand-specific bias in the nucleotide composition of the mtDNA has been known to be highly problematic for phylogenetic analyses. Here, the strand asymmetry was compared across 140 mollusc species and analyzed for a mtDNA fragment including twelve protein-coding genes. The analyses show that almost all species in Gastropoda (except Heterobranchia) and all species in Bivalvia present reversals of strand bias. The skew values on individual genes for all codon positions (P123), third codon positions (P3), and fourfold redundant third codon positions (P4FD) indicated that CG skews are the best indicators of strand asymmetry. The differences in the patterns of strand asymmetry significantly influenced the amino acid composition of the encoded proteins. These biases are most striking for the amino acids Valine, Cysteine, Asparagine and Threonines, which appear to have evolved asymmetrical exchanges in response to shifts in nucleotide composition. Molluscs with strong variability of genome architectures (ARs) are usually characterized by a reversal of the usual strand bias. Phylogenetic analyses show that reversals of asymmetric mutational constraints have consequences on the phylogenetic inferences, as taxa characterized by reverse strand bias (Heterobranchia and Bivalvia) tend to group together due to long-branch attraction (LBA) artifacts. Neutral Transitions Excluded (NTE) model did not overcome the problem of heterogeneous biases present in molluscs mt genomes, suggested it may not be appropriate for molluscs mt genome data. Further refinement phylogenetic models may help us better understand internal relationships among these diverse organisms.
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Affiliation(s)
- Shao'e Sun
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
| | - Qi Li
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, China.
| | - Lingfeng Kong
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
| | - Hong Yu
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China
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