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Arêdes DS, Rios T, Carvalho-Kelly LF, Braz V, Araripe LO, Bruno RV, Meyer-Fernandes JR, Ramos I, Gondim KC. Deficiency of Brummer lipase disturbs lipid mobilization and locomotion, and impairs reproduction due to defects in the eggshell ultrastructure in the insect vector Rhodnius prolixus. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159442. [PMID: 38042331 DOI: 10.1016/j.bbalip.2023.159442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 11/27/2023] [Accepted: 11/29/2023] [Indexed: 12/04/2023]
Abstract
Rhodnius prolixus is a hematophagous insect, which feeds on large and infrequent blood meals, and is a vector of trypanosomatids that cause Chagas disease. After feeding, lipids derived from blood meal are stored in the fat body as triacylglycerol, which is recruited under conditions of energy demand by lipolysis, where the first step is catalyzed by the Brummer lipase (Bmm), whose orthologue in mammals is the adipose triglyceride lipase (ATGL). Here, we investigated the roles of Bmm in adult Rhodnius prolixus under starvation, and after feeding. Its gene (RhoprBmm) was expressed in all the analyzed insect organs, and its transcript levels in the fat body were not altered by nutritional status. RNAi-mediated knockdown of RhoprBmm caused triacylglycerol retention in the fat body during starvation, resulting in larger lipid droplets and lower ATP levels compared to control females. The silenced females showed decreased flight capacity and locomotor activity. When RhoprBmm knockdown occurred before the blood meal and the insects were fed, the females laid fewer eggs, which collapsed and showed low hatching rates. Their hemolymph had reduced diacylglycerol content and vitellogenin concentration. The chorion (eggshell) of their eggs had no difference in hydrocarbon amounts or in dityrosine crosslinking levels compared to control eggs. However, it showed ultrastructural defects. These results demonstrated that Bmm activity is important not only to guarantee lipid mobilization to maintain energy homeostasis during starvation, but also for the production of viable eggs after a blood meal, by somehow contributing to the right formation of the egg chorion.
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Affiliation(s)
- Daniela Saar Arêdes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thamara Rios
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Valdir Braz
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luciana O Araripe
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Rafaela V Bruno
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - José Roberto Meyer-Fernandes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem - INCT-BEB/CNPq, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil.
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Vigoder FM, Araripe LO, Carvalho AB. Identification of the sex chromosome system in a sand fly species, Lutzomyia longipalpis s.l. G3 Genes|Genomes|Genetics 2021; 11:6310017. [PMID: 34849827 PMCID: PMC8496290 DOI: 10.1093/g3journal/jkab217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/10/2021] [Indexed: 11/13/2022]
Abstract
Abstract
In many animal species, sex determination is accomplished by heterogamety i.e., one of the sexes produces two types of gametes, which upon fertilization will direct the development toward males or females. Both male (“XY”) and female (“ZW”) heterogamety are known to occur and can be easily distinguished when the sex-chromosomes are morphologically different. However, this approach fails in cases of homomorphic sex chromosomes, such as the sand fly Lutzomyia longipalpis s.l. (Psychodidae, Diptera), which is the main vector of visceral leishmaniosis in Brazil. In order to identify the heterogametic sex in L. longipalpis s.l., we did a whole-genome sequencing of males and females separately and used the “Y chromosome Genome Scan” (YGS) method to find sex-specific sequences. Our results, which were confirmed by PCR, show that L. longipalpis s.l. has XY system. The YGS method can be especially useful in situations in which no morphological difference is observed in the sex-chromosomes or when fresh specimens are not readily available.
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Affiliation(s)
- Felipe M Vigoder
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS, Rio de Janeiro sl A2-075 21941-971, Brazil
| | - Luciana O Araripe
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Antonio Bernardo Carvalho
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS, Rio de Janeiro sl A2-075 21941-971, Brazil
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Santos-Araujo S, Bomfim L, Araripe LO, Bruno R, Ramos I, Gondim KC. Silencing of ATG6 and ATG8 promotes increased levels of triacylglycerol (TAG) in the fat body during prolonged starvation periods in the Chagas disease vector Rhodnius prolixus. Insect Biochem Mol Biol 2020; 127:103484. [PMID: 33022370 DOI: 10.1016/j.ibmb.2020.103484] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/18/2020] [Accepted: 09/29/2020] [Indexed: 06/11/2023]
Abstract
Rhodnius prolixus is an obligatorily hematophagous insect known as an important vector of Chagas disease. Autophagy is a conserved cellular mechanism that acts in response to nutrient starvation, where components of the cytoplasm are sequestered by a double membrane organelle, named autophagosome, which is targeted to fuse with the lysosome for degradation. Lipophagy is the process of lipid degradation by selective autophagy, where autophagosomes sequester lipid droplets and degrade triacylglycerol (TAG) generating free fatty acids for β-oxidation. Here, two essential genes of the autophagic pathway, Atg6/Beclin1 (RpAtg6) and Atg8/LC3 (RpAtg8), were silenced and the storage of lipids during starvation in Rhodnius prolixus was monitored. We found that RNAi knockdown of both RpAtg6 and RpAtg8 resulted in higher levels of TAG in the fat body and the flight muscle, 24 days after the blood meal, as well as a larger average diameter of the lipid droplets in the fat body, as seen by Nile Red staining under the confocal fluorescence microscope. Silenced starved insects had lower survival rates when compared to control insects. Accordingly, when examined during the starvation period for monitored activity, silenced insects had lower spontaneous locomotor activity and lower forced flight rates. Furthermore, we found that some genes involved in lipid metabolism had their expression levels altered in silenced insects, such as the Brummer lipase (down regulated) and the adipokinetic hormone receptor (up regulated), suggesting that, as previously observed in mammalian models, the autophagy and neutral lipolysis machineries are interconnected at the transcriptional level. Altogether, our data indicate that autophagy in the fat body is important to allow insects to mobilize energy from lipid stores.
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Affiliation(s)
- Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Larissa Bomfim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Luciana O Araripe
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz. Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Rafaela Bruno
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz. Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil.
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Araripe LO, Tao Y, Lemos B. Interspecific Y chromosome variation is sufficient to rescue hybrid male sterility and is influenced by the grandparental origin of the chromosomes. Heredity (Edinb) 2016; 116:516-22. [PMID: 26980343 DOI: 10.1038/hdy.2016.11] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 11/25/2015] [Accepted: 12/29/2015] [Indexed: 12/15/2022] Open
Abstract
Y chromosomes display population variation within and between species. Co-evolution within populations is expected to produce adaptive interactions between Y chromosomes and the rest of the genome. One consequence is that Y chromosomes from disparate populations could disrupt harmonious interactions between co-evolved genetic elements and result in reduced male fertility, sterility or inviability. Here we address the contribution of 'heterospecific Y chromosomes' to fertility in hybrid males carrying a homozygous region of Drosophila mauritiana introgressed in the Drosophila simulans background. In order to detect Y chromosome-autosome interactions, which may go unnoticed in a single-species background of autosomes, we constructed hybrid genotypes involving three sister species: Drosophila simulans, D. mauritiana, and D. sechellia. These engineered strains varied due to: (i) species origin of the Y chromosome (D. simulans or D. sechellia); (ii) location of the introgressed D. mauritiana segment on the D. simulans third chromosome, and (iii) grandparental genomic background (three genotypes of D. simulans). We find complex interactions between the species origin of the Y chromosome, the identity of the D. mauritiana segment and the grandparental genetic background donating the chromosomes. Unexpectedly, the interaction of the Y chromosome and one segment of D. mauritiana drastically reduced fertility in the presence of Ysim, whereas the fertility is partially rescued by the Y chromosome of D. sechellia when it descends from a specific grandparental genotype. The restoration of fertility occurs in spite of an autosomal and X-linked genome that is mostly of D. simulans origin. These results illustrate the multifactorial basis of genetic interactions involving the Y chromosome. Our study supports the hypothesis that the Y chromosome can contribute significantly to the evolution of reproductive isolation and highlights the conditional manifestation of infertility in specific genotypic combinations.
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Affiliation(s)
- L O Araripe
- Laboratório de Biologia Molecular de Insetos, Fundação Oswaldo Cruz, IOC, Rio de Janeiro, Brasil
| | - Y Tao
- Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, USA
| | - B Lemos
- Program in Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA, USA
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Araripe LO, Montenegro H, Lemos B, Hartl DL. Fine-scale genetic mapping of a hybrid sterility factor between Drosophila simulans and D. mauritiana: the varied and elusive functions of "speciation genes". BMC Evol Biol 2010; 10:385. [PMID: 21144061 PMCID: PMC3020225 DOI: 10.1186/1471-2148-10-385] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 12/14/2010] [Indexed: 11/10/2022] Open
Abstract
Background Hybrid male sterility (HMS) is a usual outcome of hybridization between closely related animal species. It arises because interactions between alleles that are functional within one species may be disrupted in hybrids. The identification of genes leading to hybrid sterility is of great interest for understanding the evolutionary process of speciation. In the current work we used marked P-element insertions as dominant markers to efficiently locate one genetic factor causing a severe reduction in fertility in hybrid males of Drosophila simulans and D. mauritiana. Results Our mapping effort identified a region of 9 kb on chromosome 3, containing three complete and one partial coding sequences. Within this region, two annotated genes are suggested as candidates for the HMS factor, based on the comparative molecular characterization and public-source information. Gene Taf1 is partially contained in the region, but yet shows high polymorphism with four fixed non-synonymous substitutions between the two species. Its molecular functions involve sequence-specific DNA binding and transcription factor activity. Gene agt is a small, intronless gene, whose molecular function is annotated as methylated-DNA-protein-cysteine S-methyltransferase activity. High polymorphism and one fixed non-synonymous substitution suggest this is a fast evolving gene. The gene trees of both genes perfectly separate D. simulans and D. mauritiana into monophyletic groups. Analysis of gene expression using microarray revealed trends that were similar to those previously found in comparisons between whole-genome hybrids and parental species. Conclusions The identification following confirmation of the HMS candidate gene will add another case study leading to understanding the evolutionary process of hybrid incompatibility.
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Affiliation(s)
- Luciana O Araripe
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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Abstract
The paucity of polymorphisms in single-copy genes on the Y chromosome of Drosophila contrasts with data indicating that this chromosome has polymorphic phenotypic effects on sex ratio, temperature sensitivity, behavior, and fitness. We show that the Y chromosome of D. melanogaster harbors substantial genetic diversity in the form of polymorphisms for genetic elements that differentially affect the expression of hundreds of X-linked and autosomal genes. The affected genes are more highly expressed in males, more meagerly expressed in females, and more highly divergent between species. Functionally, they affect microtubule stability, lipid and mitochondrial metabolism, and the thermal sensitivity of spermatogenesis. Our findings provide a mechanism for adaptive phenotypic variation associated with the Y chromosome.
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Affiliation(s)
- Bernardo Lemos
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Avenue, Cambridge, MA 02138, USA.
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David JR, Araripe LO, Bitner-Mathé BC, Capy P, Goñi B, Klaczko LB, Legout H, Martins MB, Vouidibio J, Yassin A, Moreteau B. Sexual dimorphism of body size and sternopleural bristle number: a comparison of geographic populations of an invasive cosmopolitan drosophilid. Genetica 2006; 128:109-22. [PMID: 17028944 DOI: 10.1007/s10709-005-5539-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2005] [Accepted: 11/28/2005] [Indexed: 10/24/2022]
Abstract
Zaprionus indianus is a cosmopolitan drosophilid, of Afrotropical origin, which has recently colonized South America. The sexual dimorphism (SD) of body size is low, males being almost as big as females. We investigated 10 natural populations, 5 from America and 5 from Africa, using the isofemale line technique. Three traits were measured on each fly: wing and thorax length and sternopleural bristle number. Two indices of SD were compared, and found to be highly correlated (r > 0.99). For the sake of simplicity, only the female/male (F/M) ratio was further considered. A significant genetic variability of SD was found in all cases, although with a low heritability (intra-class correlation of 0.13), about half the value found for the traits themselves. For size SD, we did not find any variation among continents or any latitudinal trend, and average values were 1.02 for wing length and 1.01 for thorax length. Bristle number SD was much greater (1.07). Among mass laboratory strains, SD was genetically much more variable than in recently collected populations, a likely consequence of laboratory drift. Altogether, SD, although genetically variable and prone to laboratory drift, is independent of size variations and presumably submitted to a stabilizing selection in nature.
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Affiliation(s)
- Jean R David
- CNRS, Lab. Populations, Génétique et Evolution, Gif sur Yvette Cedex, 91198, France.
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Araripe LO, Aprigliano P, Olifiers N, Borodin P, Cerqueira R. Comparative analysis of life-history traits in two species of C alomys (Rodentia: Sigmodontinae) in captivity / Analyse comparative des traits d'histoire de vie de deux espèces de Calomys (Rodentia: Sigmodontinae) en captivité. MAMMALIA 2006. [DOI: 10.1515/mamm.70.1-2.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractWe analyzed life-history traits (fertility, growth and rate of postnatal development) in captive-bred colonies of two closely related sympatric species: Calomys expulsus and C. tener (Rodentia, Sigmodontinae). We found significant differences between the species in growth rate and several reproductive traits. C. tener had a smaller litter size and litter mass, smaller proportion of litter mass to maternal mass, lower growth rate and higher infant mortality. We also found an apparent difference in correlation patterns of life history parameters between the two species of Calomys . The strong correlation between body size and fecundity found in other studies of life history traits and in selection experiments seems to be disrupted in C. tener . We found a significant positive correlation between maternal mass and litter size and mass only for C. expulsus, which means that in C. tener the fertility of females does not depend strongly on body mass. We discuss inbreeding depression and stress reactions as possible reasons for these results.
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Araripe LO, Aprigliano P, Olifiers N, Borodin P, Cerqueira R. Comparative analysis of life-history traits in two species of C alomys (Rodentia: Sigmodontinae) in captivity / Analyse comparative des traits d'histoire de vie de deux espèces de Calomys (Rodentia: Sigmodontinae) en captivité. MAMMALIA 2006. [DOI: 10.1515/mamm.2006.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractWe analyzed life-history traits (fertility, growth and rate of postnatal development) in captive-bred colonies of two closely related sympatric species: Calomys expulsus and C. tener (Rodentia, Sigmodontinae). We found significant differences between the species in growth rate and several reproductive traits. C. tener had a smaller litter size and litter mass, smaller proportion of litter mass to maternal mass, lower growth rate and higher infant mortality. We also found an apparent difference in correlation patterns of life history parameters between the two species of Calomys . The strong correlation between body size and fecundity found in other studies of life history traits and in selection experiments seems to be disrupted in C. tener . We found a significant positive correlation between maternal mass and litter size and mass only for C. expulsus, which means that in C. tener the fertility of females does not depend strongly on body mass. We discuss inbreeding depression and stress reactions as possible reasons for these results.
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David JR, Araripe LO, Bitner-Mathé BC, Capy P, Goñi B, Klaczko LB, Legout H, Martins MB, Vouidibio J, Yassin A, Moreteau B. Quantitative trait analysis and geographic variability of natural populations of Zaprionus indianus, a recent invader in Brazil. Heredity (Edinb) 2005; 96:53-62. [PMID: 16222328 DOI: 10.1038/sj.hdy.6800753] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Five natural samples of a recent South America invader, the drosophilid Zaprionus indianus, were investigated with the isofemale line technique. These samples were compared to five African mainland populations, investigated with the same method. The results were also compared to data obtained on mass cultures of other populations from Africa and India. Three quantitative traits were measured on both sexes, wing and thorax length and sternopleural bristle number. We did not find any latitudinal trend among the American samples, while a significant increase in body size with latitude was observed in the Indian and, to a lesser degree, in the African populations. American populations were also characterized by their bigger size. Genetic variability, estimated by the intraclass correlation among isofemale lines, was similar in American and African populations. The intraline, nongenetic variability was significantly less in the American samples, suggesting a better developmental stability, the origin of which is unclear. A positive relationship was evident between intraline variability of size traits and the wing-thorax length correlation. Altogether, our data suggest that the colonizing propagule introduced to Brazil had a fairly large size, preventing any bottleneck effect being detected. The big body size of American flies suggests that they came from a high-latitude African country. The lack of a latitudinal dine in America seems to be related to the short time elapsed since introduction. The very rapid spread of Z. indianus all over South America suggests that it might rapidly invade North America.
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Affiliation(s)
- J R David
- CNRS, Lab. Populations, Génétique et Evolution, 91198 Gif sur Yvette, France.
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David JR, Araripe LO, Chakir M, Legout H, Lemos B, Pétavy G, Rohmer C, Joly D, Moreteau B. Male sterility at extreme temperatures: a significant but neglected phenomenon for understanding Drosophila climatic adaptations. J Evol Biol 2005; 18:838-46. [PMID: 16033555 DOI: 10.1111/j.1420-9101.2005.00914.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The thermal range for viability is quite variable among Drosophila species and it has long been known that these variations are correlated with geographic distribution: temperate species are on average more cold tolerant but more heat sensitive than tropical species. At both ends of their viability range, sterile males have been observed in all species investigated so far. This symmetrical phenomenon restricts the temperature limits within which permanent cultures can be kept in the laboratory. Thermal heat sterility thresholds are very variable across species from 23 degrees C in heat sensitive species up to 31 degrees C in heat tolerant species. In Drosophila melanogaster, genetic variations are observed among geographic populations. Tropical populations are more tolerant to heat induced sterility and recover more rapidly than temperate ones. A genetic analysis revealed that about 50% of the difference observed between natural populations was due to the Y chromosome. Natural populations have not reached a selection limit, however: thermal tolerance was still increased by keeping strains at a high temperature, close to the sterility threshold. On the low temperature side, a symmetrical reverse phenomenon seems to exist: temperate populations are more tolerant to cold than tropical ones. Compared to Mammals, drosophilids exhibit two major differences: first, male sterility occurs not only at high temperature, but also at a low temperature; second, sterility thresholds are not evolutionarily constrained, but highly variable. Altogether, significant and sometimes major genetic variations have been observed between species, between geographic races of the same species, and even between strains kept in the laboratory under different thermal regimes. In each case, it is easily argued that the observed variations correspond to adaptations to climatic conditions, and that male sterility is a significant component of fitness and a target of natural selection.
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Affiliation(s)
- J R David
- CNRS, Laboratoire Populations, Génétique et Evolution, Gif-sur-Yvette Cedex, France.
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Aulchenko YS, Araripe LO, D'Andrea PS, Shishkin AA, Cerqueira R, Borodin PM, Axenovich TI. Inheritance of litter size at birth in the Brazilian grass mouse (Akodon cursor, Sigmodontinae, Rodentia). Genet Res (Camb) 2002; 80:55-62. [PMID: 12448858 DOI: 10.1017/s0016672302005724] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
By means of complex segregation analysis we studied the inheritance of litter size in two large pedigrees of captive-bred colonies of the Brazilian grass mouse Akodon cursor. Genetic analysis has revealed a highly significant influence of genetic factors on the variation of litter size (heritability, h2, was estimated as 0.44). The inheritance followed the classical polygene model: neither the major-gene model nor the polygene with unequal contribution model described the data significantly better.
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Affiliation(s)
- Yu S Aulchenko
- Institute of Cytology and Genetics, Russian Academy of Science, 630090 Novosibirsk, Russia
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