1
|
Polinski JM, Castellano KR, Buckley KM, Bodnar AG. Genomic signatures of exceptional longevity and negligible aging in the long-lived red sea urchin. Cell Rep 2024; 43:114021. [PMID: 38564335 DOI: 10.1016/j.celrep.2024.114021] [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: 08/08/2023] [Revised: 02/12/2024] [Accepted: 03/15/2024] [Indexed: 04/04/2024] Open
Abstract
The red sea urchin (Mesocentrotus franciscanus) is one of the Earth's longest-living animals, reported to live more than 100 years with indeterminate growth, life-long reproduction, and no increase in mortality rate with age. To understand the genetic underpinnings of longevity and negligible aging, we constructed a chromosome-level assembly of the red sea urchin genome and compared it to that of short-lived sea urchin species. Genome-wide syntenic alignments identified chromosome rearrangements that distinguish short- and long-lived species. Expanded gene families in long-lived species play a role in innate immunity, sensory nervous system, and genome stability. An integrated network of genes under positive selection in the red sea urchin was involved in genomic regulation, mRNA fidelity, protein homeostasis, and mitochondrial function. Our results implicated known longevity genes in sea urchin longevity but also revealed distinct molecular signatures that may promote long-term maintenance of tissue homeostasis, disease resistance, and negligible aging.
Collapse
Affiliation(s)
| | | | | | - Andrea G Bodnar
- Gloucester Marine Genomics Institute, Gloucester, MA 01930, USA.
| |
Collapse
|
2
|
Vacquier VD, Hamdoun A. Cold storage and cryopreservation methods for spermatozoa of the sea urchins Lytechinus pictus and Strongylocentrotus purpuratus. Dev Dyn 2024. [PMID: 38340021 DOI: 10.1002/dvdy.691] [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: 10/04/2023] [Revised: 12/06/2023] [Accepted: 12/10/2023] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND Sea urchins have contributed greatly to knowledge of fertilization, embryogenesis, and cell biology. However, until now, they have not been genetic model organisms because of their long generation times and lack of tools for husbandry and gene manipulation. We recently established the sea urchin Lytechinus pictus, as a multigenerational model Echinoderm, because of its relatively short generation time of 4-6 months and ease of laboratory culture. To take full advantage of this new multigenerational species, methods are needed to biobank and share genetically modified L. pictus sperm. RESULTS Here, we describe a method, based on sperm ion physiology that maintains L. pictus and Strongylocentrotus purpuratus sperm fertilizable for at least 5-10 weeks when stored at 0°C. We also describe a new method to cryopreserve sperm of both species. Sperm of both species can be frozen and thawed at least twice and still give rise to larvae that undergo metamorphosis. CONCLUSIONS The simple methods we describe work well for both species, achieving >90% embryo development and producing larvae that undergo metamorphosis to juvenile adults. We hope that these methods will be useful to others working on marine invertebrate sperm.
Collapse
Affiliation(s)
- Victor D Vacquier
- Center for Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| | - Amro Hamdoun
- Center for Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| |
Collapse
|
3
|
Pieplow CA, Furze AR, Wessel GM. A case of hermaphroditism in the gonochoristic sea urchin, Strongylocentrotus purpuratus, reveals key mechanisms of sex determination†. Biol Reprod 2023; 108:960-973. [PMID: 36943312 PMCID: PMC10266946 DOI: 10.1093/biolre/ioad036] [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: 11/22/2022] [Revised: 01/20/2023] [Accepted: 03/08/2023] [Indexed: 03/23/2023] Open
Abstract
Sea urchins are usually gonochoristic, with all of their five gonads either testes or ovaries. Here, we report an unusual case of hermaphroditism in the purple sea urchin, Strongylocentrotus purpuratus. The hermaphrodite is self-fertile, and one of the gonads is an ovotestis; it is largely an ovary with a small segment containing fully mature sperm. Molecular analysis demonstrated that each gonad producedviable gametes, and we identified for the first time a somatic sex-specific marker in this phylum: Doublesex and mab-3 related transcription factor 1 (DMRT1). This finding also enabled us to analyze the somatic tissues of the hermaphrodite, and we found that the oral tissues (including gut) were out of register with the aboral tissues (including tube feet) enabling a genetic lineage analysis. Results from this study support a genetic basis of sex determination in sea urchins, the viability of hermaphroditism, and distinguish gonad determination from somatic tissue organization in the adult.
Collapse
Affiliation(s)
- Cosmo A Pieplow
- Department of Molecular Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Aidan R Furze
- Department of Molecular Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Gary M Wessel
- Department of Molecular Biology and Biochemistry, Brown University, Providence, RI, USA
| |
Collapse
|
4
|
de Santiago WGA, Muñoz-Alvarez AI, Díaz-Martínez JP, Benítez-Villalobos F. Resemblances in the early development of two sea urchins: Toxopneustes roseus (Euechinoidea: Echinacea) and Rhyncholampas pacificus (Euechinoidea: Irregularia) from different habitats in the southern Mexican Pacific. Dev Biol 2023; 499:1-9. [PMID: 37085002 DOI: 10.1016/j.ydbio.2023.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 04/10/2023] [Accepted: 04/18/2023] [Indexed: 04/23/2023]
Abstract
Sea urchins play a key role in the marine environment, contributing to maintain a balance in benthic ecosystems. Toxopneustes roseus acts as a regulator of rhodolith beds and is a key species as a bioturbation promoter, while Rhyncholampas pacificus moderates the detritus content of sediment through various mechanisms and contributes to accelerating the circulation of organic matter. However, nothing is known about their early development, so the objective of this research is to characterize the embryonic and larval development of specimens of the two species from the southern Mexican Pacific and identify the causes that produce their differences. The embryonic development of T. roseus lasted approximately 20 h; the echinopluteus larva appeared at 23 h and culminated in around 12 days with an eight-armed larva. Metamorphosis was reached at 18 days. The embryonic development of R. pacificus lasted about 15 h; the larva emerged at 20 h and culminated in about two days with an eight-armed larva. The metamorphosis was completed in 9 days. The reproductive output of both species determines their development time and the structure of their larvae; therefore, the energy of R. pacificus is invested in reaching metamorphosis earlier to ensure that its larvae, which are not very abundant, settle and recruit to the population. Regarding T. roseus, the longest permanence in the plankton is efficiently maintained by its numerous larvae through the presence of mobile arms and the shift of the swimming function to the epauletes. This is the first work that characterizes the early development of a species of the genus Toxopneustes and of the only living species of the genus Ryncholampas. The information generated in this work is essential to gaining knowledge about these groups of echinoids, especially the effect of the environment on their early development.
Collapse
Affiliation(s)
- Walter Germán Alonso de Santiago
- División de Estudios de Posgrado, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico; Laboratorio de Ecología del Desarrollo, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico
| | - Astrid Itzel Muñoz-Alvarez
- Laboratorio de Ecología del Desarrollo, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico
| | - Julia Patricia Díaz-Martínez
- Laboratorio de Ecología del Desarrollo, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico
| | - Francisco Benítez-Villalobos
- Laboratorio de Ecología del Desarrollo, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico; Instituto de Recursos, Universidad del Mar (UMAR), Campus Puerto Ángel, Distrito de San Pedro Pochutla, Puerto Ángel, Oaxaca, C.P. 70902, Mexico.
| |
Collapse
|
5
|
Formery L, Wakefield A, Gesson M, Toisoul L, Lhomond G, Gilletta L, Lasbleiz R, Schubert M, Croce JC. Developmental atlas of the indirect-developing sea urchin Paracentrotus lividus: From fertilization to juvenile stages. Front Cell Dev Biol 2022; 10:966408. [DOI: 10.3389/fcell.2022.966408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/26/2022] [Indexed: 11/13/2022] Open
Abstract
The sea urchin Paracentrotus lividus has been used as a model system in biology for more than a century. Over the past decades, it has been at the center of a number of studies in cell, developmental, ecological, toxicological, evolutionary, and aquaculture research. Due to this previous work, a significant amount of information is already available on the development of this species. However, this information is fragmented and rather incomplete. Here, we propose a comprehensive developmental atlas for this sea urchin species, describing its ontogeny from fertilization to juvenile stages. Our staging scheme includes three periods divided into 33 stages, plus 15 independent stages focused on the development of the coeloms and the adult rudiment. For each stage, we provide a thorough description based on observations made on live specimens using light microscopy, and when needed on fixed specimens using confocal microscopy. Our descriptions include, for each stage, the main anatomical characteristics related, for instance, to cell division, tissue morphogenesis, and/or organogenesis. Altogether, this work is the first of its kind providing, in a single study, a comprehensive description of the development of P. lividus embryos, larvae, and juveniles, including details on skeletogenesis, ciliogenesis, myogenesis, coelomogenesis, and formation of the adult rudiment as well as on the process of metamorphosis in live specimens. Given the renewed interest for the use of sea urchins in ecotoxicological, developmental, and evolutionary studies as well as in using marine invertebrates as alternative model systems for biomedical investigations, this study will greatly benefit the scientific community and will serve as a reference for specialists and non-specialists interested in studying sea urchins.
Collapse
|
6
|
Barone V, Lyons DC. Live imaging of echinoderm embryos to illuminate evo-devo. Front Cell Dev Biol 2022; 10:1007775. [PMID: 36187474 PMCID: PMC9521734 DOI: 10.3389/fcell.2022.1007775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
Echinoderm embryos have been model systems for cell and developmental biology for over 150 years, in good part because of their optical clarity. Discoveries that shaped our understanding of fertilization, cell division and cell differentiation were only possible because of the transparency of sea urchin eggs and embryos, which allowed direct observations of intracellular structures. More recently, live imaging of sea urchin embryos, coupled with fluorescence microscopy, has proven pivotal to uncovering mechanisms of epithelial to mesenchymal transition, cell migration and gastrulation. However, live imaging has mainly been performed on sea urchin embryos, while echinoderms include numerous experimentally tractable species that present interesting variation in key aspects of morphogenesis, including differences in embryo compaction and mechanisms of blastula formation. The study of such variation would allow us not only to understand how tissues are formed in echinoderms, but also to identify which changes in cell shape, cell-matrix and cell-cell contact formation are more likely to result in evolution of new embryonic shapes. Here we argue that adapting live imaging techniques to more echinoderm species will be fundamental to exploit such an evolutionary approach to the study of morphogenesis, as it will allow measuring differences in dynamic cellular behaviors - such as changes in cell shape and cell adhesion - between species. We briefly review existing methods for live imaging of echinoderm embryos and describe in detail how we adapted those methods to allow long-term live imaging of several species, namely the sea urchin Lytechinus pictus and the sea stars Patiria miniata and Patiriella regularis. We outline procedures to successfully label, mount and image early embryos for 10–16 h, from cleavage stages to early blastula. We show that data obtained with these methods allows 3D segmentation and tracking of individual cells over time, the first step to analyze how cell shape and cell contact differ among species. The methods presented here can be easily adopted by most cell and developmental biology laboratories and adapted to successfully image early embryos of additional species, therefore broadening our understanding of the evolution of morphogenesis.
Collapse
|
7
|
Lineage tracing shows that cell size asymmetries predict the dorsoventral axis in the sea star embryo. BMC Biol 2022; 20:179. [PMID: 35971116 PMCID: PMC9380389 DOI: 10.1186/s12915-022-01359-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/23/2022] [Indexed: 11/21/2022] Open
Abstract
Background Cell size asymmetries are often linked to cell fate decisions, due to cell volumes and cell fate determinants being unequally partitioned during asymmetric cell divisions. A clear example is found in the sea urchin embryo, where a characteristic and obvious unequal 4th cleavage generates micromeres, which are necessary for mesendoderm cell fate specification. Unlike sea urchin development, sea star development is generally thought to have only equal cleavage. However, subtle cell size asymmetries can be observed in sea star embryos; whether those cell size asymmetries are consistently produced during sea star development and if they are involved in cell fate decisions remains unknown. Results Using confocal live imaging of early embryos we quantified cell size asymmetries in 16-cell stage embryos of two sea star species, Patiria miniata and Patiriella regularis. Using photoconversion to perform lineage tracing, we find that the position of the smallest cells of P. miniata embryos is biased toward anterior ventral tissues. However, both blastomere dissociation and mechanical removal of one small cell do not prevent dorsoventral (DV) axis formation, suggesting that embryos compensate for the loss of those cells and that asymmetrical partitioning of maternal determinants is not strictly necessary for DV patterning. Finally, we show that manipulating cell size to introduce artificial cell size asymmetries is not sufficient to direct the positioning of the future DV axis in P. miniata embryos. Conclusions Our results show that although cell size asymmetries are consistently produced during sea star early cleavage and are predictive of the DV axis, they are not necessary to instruct DV axis formation. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01359-3.
Collapse
|
8
|
Vyas H, Schrankel CS, Espinoza JA, Mitchell KL, Nesbit KT, Jackson E, Chang N, Lee Y, Warner J, Reitzel A, Lyons DC, Hamdoun A. Generation of a homozygous mutant drug transporter (ABCB1) knockout line in the sea urchin Lytechinus pictus. Development 2022; 149:275601. [PMID: 35666622 PMCID: PMC9245184 DOI: 10.1242/dev.200644] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/05/2022] [Indexed: 11/20/2022]
Abstract
ABSTRACT
Sea urchins are premier model organisms for the study of early development. However, the lengthy generation times of commonly used species have precluded application of stable genetic approaches. Here, we use the painted sea urchin Lytechinus pictus to address this limitation and to generate a homozygous mutant sea urchin line. L. pictus has one of the shortest generation times of any currently used sea urchin. We leveraged this advantage to generate a knockout mutant of the sea urchin homolog of the drug transporter ABCB1, a major player in xenobiotic disposition for all animals. Using CRISPR/Cas9, we generated large fragment deletions of ABCB1 and used these readily detected deletions to rapidly genotype and breed mutant animals to homozygosity in the F2 generation. The knockout larvae are produced according to expected Mendelian distribution, exhibit reduced xenobiotic efflux activity and can be grown to maturity. This study represents a major step towards more sophisticated genetic manipulation of the sea urchin and the establishment of reproducible sea urchin animal resources.
Collapse
Affiliation(s)
- Himanshu Vyas
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Catherine S. Schrankel
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Jose A. Espinoza
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Kasey L. Mitchell
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Katherine T. Nesbit
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Elliot Jackson
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Nathan Chang
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Yoon Lee
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Jacob Warner
- University of North Carolina Wilmington 2 Department of Biology and Marine Biology , , Wilmington, NC 28403-5915 , USA
| | - Adam Reitzel
- University of North Carolina Charlotte 3 Department of Biological Sciences , , Charlotte, NC 28223-0001 , USA
| | - Deirdre C. Lyons
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| | - Amro Hamdoun
- Center for Marine Biotechnology and Biomedicine 1 , , , La Jolla, CA 92093-0202 , USA
- Scripps Institution of Oceanography 1 , , , La Jolla, CA 92093-0202 , USA
- University of California San Diego 1 , , , La Jolla, CA 92093-0202 , USA
| |
Collapse
|
9
|
Tokanai K, Kamei Y, Minokawa T. An easy and rapid staining method for confocal microscopic observation and reconstruction of three-dimensional images of echinoderm larvae and juveniles. Dev Growth Differ 2021; 63:478-487. [PMID: 34747504 DOI: 10.1111/dgd.12758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/17/2021] [Accepted: 09/28/2021] [Indexed: 01/18/2023]
Abstract
The morphologies of the internal organs of echinoderm larvae and juveniles are difficult to study using conventional optical microscopes because of their structural complexity and opaqueness. This paper describes an easy and rapid protocol involving Nile blue staining followed by benzyl alcohol/benzyl benzoate (BABB) clearing to overcome this limitation. This method was developed for a three-dimensional (3D) analysis of the internal structures of advanced larvae and juveniles of echinoderms (the sea lily Metacrinus rotundus, the sea urchin Hemicentrotus pulcherrimus, and the sand dollar Scaphechinus mirabilis) and is suitable for obtaining serial optical images by confocal microscopy without the use of specific antibodies or special reagents for labeling. Nile blue is an easy-to-use stain that offers several advantages for confocal microscopy such as it can stain various tissues with strong fluorescent signals without substantial bleaching during observation. We found that the strong fluorescence signal of Nile blue quickly yielded clear high-resolution optical section images for 3D reconstruction. BABB clearing rendered opaque larvae highly transparent. The clearing procedure was also easy and quick. During the process, agarose embedding prior to staining and clearing was found to be critical for handling the samples of less than 500-μm length and stabilizing their orientations. To conclude, the protocol described is useful for performing a rapid and accurate 3D morphological analysis of echinoderm larvae and juveniles.
Collapse
Affiliation(s)
- Kohei Tokanai
- Research Center for Marine Biology, Graduate School of Life Sciences, Tohoku University, Aomori, Japan
| | - Yasuhiro Kamei
- Spectrography and Bioimaging Facility, National Institute for Basic Biology Core Research Facilities, National Institute for Basic Biology, Aichi, Japan
| | - Takuya Minokawa
- Research Center for Marine Biology, Graduate School of Life Sciences, Tohoku University, Aomori, Japan
| |
Collapse
|
10
|
Vacquier VD, Hamdoun A. New techniques for creating parthenogenetic larvae of the sea urchin Lytechinus pictus for gene expression studies. Dev Dyn 2021; 250:1828-1833. [PMID: 34042247 DOI: 10.1002/dvdy.377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/21/2021] [Accepted: 05/13/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Sea urchins are model organisms for studying the spatial-temporal control of gene activity during development. The Southern California species, Lytechinus pictus, has a sequenced genome and can be raised in the laboratory from egg to egg in 4 to 5 months. RESULTS Here, we present new techniques for generating parthenogenetic larvae of this species and include a gallery of photomicrographs of morphologically abnormal larvae that could be used for transcriptomic analysis. CONCLUSIONS Comparison of gene expression in parthenogenotes to larvae produced by fertilization could provide novel insights into gene expression controls contributed by sperm in this important model organism. Knowledge gained from transcriptomics of sea urchin parthenogenotes could contribute to parthenogenetic studies of mammalian embryos.
Collapse
Affiliation(s)
- Victor D Vacquier
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| | - Amro Hamdoun
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| |
Collapse
|
11
|
Warner JF, Lord JW, Schreiter SA, Nesbit KT, Hamdoun A, Lyons DC. Chromosomal-Level Genome Assembly of the Painted Sea Urchin Lytechinus pictus: A Genetically Enabled Model System for Cell Biology and Embryonic Development. Genome Biol Evol 2021; 13:evab061. [PMID: 33769486 PMCID: PMC8085125 DOI: 10.1093/gbe/evab061] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2021] [Indexed: 02/06/2023] Open
Abstract
The painted urchin Lytechinus pictus is a sea urchin in the family Toxopneustidae and one of several sea urchin species that are routinely used as an experimental research organism. Recently, L. pictus has emerged as a tractable model system for establishing transgenic sea urchin lines due to its amenability to long term laboratory culture. We present the first published genome of L. pictus. This chromosomal-level assembly was generated using Illumina sequencing in conjunction with Oxford Nanopore Technologies long read sequencing and HiC chromatin conformation capture sequencing. The 998.9-Mb assembly exhibits high contiguity and has a scaffold length N50 of 46.0 Mb with 97% of the sequence assembled into 19 chromosomal-length scaffolds. These 19 scaffolds exhibit a high degree of synteny compared with the 19 chromosomes of a related species Lytechinus variegatus. Ab initio and transcript evidence gene modeling, combined with sequence homology, identified 28,631 gene models that capture 92% of BUSCO orthologs. This annotation strategy was validated by manual curation of gene models for the ABC transporter superfamily, which confirmed the completeness and accuracy of the annotations. Thus, this genome assembly, in conjunction with recent high contiguity assemblies of related species, positions L. pictus as an exceptional model system for comparative functional genomics and it will be a key resource for the developmental, toxicological, and ecological biology scientific communities.
Collapse
Affiliation(s)
- Jacob F Warner
- Department of Biology and Marine Biology, University of North Carolina Wilmington, North Carolina, USA
| | - James W Lord
- Department of Biology and Marine Biology, University of North Carolina Wilmington, North Carolina, USA
| | - Samantha A Schreiter
- Department of Biology and Marine Biology, University of North Carolina Wilmington, North Carolina, USA
| | - Katherine T Nesbit
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| | - Amro Hamdoun
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| | - Deirdre C Lyons
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA
| |
Collapse
|