Yano A.,French National Institute for Agricultural Research |
Guyomard R.,French National Institute for Agricultural Research |
Nicol B.,French National Institute for Agricultural Research |
Jouanno E.,French National Institute for Agricultural Research |
And 7 more authors.
Current Biology | Year: 2012
Since the discovery of Sry in mammals [1, 2], few other master sex-determining genes have been identified in vertebrates [3-7]. To date, all of these genes have been characterized as well-known factors in the sex differentiation pathway, suggesting that the same subset of genes have been repeatedly and independently selected throughout evolution as master sex determinants [8, 9]. Here, we characterized in rainbow trout an unknown gene expressed only in the testis, with a predominant expression during testicular differentiation. This gene is a male-specific genomic sequence that is colocalized along with the sex-determining locus. This gene, named sdY for sexually dimorphic on the Y chromosome, encodes a protein that displays similarity to the C-terminal domain of interferon regulatory factor 9. The targeted inactivation of sdY in males using zinc-finger nuclease induces ovarian differentiation, and the overexpression of sdY in females using additive transgenesis induces testicular differentiation. Together, these results demonstrate that sdY is a novel vertebrate master sex-determining gene not related to any known sex-differentiating gene. These findings highlight an unexpected evolutionary plasticity in vertebrate sex determination through the demonstration that master sex determinants can arise from the de novo evolution of genes that have not been previously implicated in sex differentiation. © 2012 Elsevier Ltd.
Demars J.,French National Institute for Agricultural Research |
Demars J.,Laboratoire Of Genetique Cellulaire |
Fabre S.,French National Institute for Agricultural Research |
Fabre S.,Laboratoire Of Genetique Cellulaire |
And 15 more authors.
PLoS Genetics | Year: 2013
Some sheep breeds are naturally prolific, and they are very informative for the studies of reproductive genetics and physiology. Major genes increasing litter size (LS) and ovulation rate (OR) were suspected in the French Grivette and the Polish Olkuska sheep populations, respectively. To identify genetic variants responsible for the highly prolific phenotype in these two breeds, genome-wide association studies (GWAS) followed by complementary genetic and functional analyses were performed. Highly prolific ewes (cases) and normal prolific ewes (controls) from each breed were genotyped using the Illumina OvineSNP50 Genotyping Beadchip. In both populations, an X chromosome region, close to the BMP15 gene, harbored clusters of markers with suggestive evidence of association at significance levels between 1E-05 and 1E-07. The BMP15 candidate gene was then sequenced, and two novel non-conservative mutations called FecXGr and FecXO were identified in the Grivette and Olkuska breeds, respectively. The two mutations were associated with the highly prolific phenotype (pFecX Gr = 5.98E-06 and pFecX O = 2.55E-08). Homozygous ewes for the mutated allele showed a significantly increased prolificacy (FecXGr/FecXGr, LS = 2.50±0.65 versus FecX+/FecXGr, LS = 1.93±0.42, p<1E-03 and FecXO/FecXO, OR = 3.28±0.85 versus FecX+/FecXO, OR = 2.02±0.47, p<1E-03). Both mutations are located in very well conserved motifs of the protein and altered the BMP15 signaling activity in vitro using a BMP-responsive luciferase test in COV434 granulosa cells. Thus, we have identified two novel mutations in the BMP15 gene associated with increased LS and OR. Notably, homozygous FecXGr/FecXGr Grivette and homozygous FecXO/FecXO Olkuska ewes are hyperprolific in striking contrast with the sterility exhibited by all other known homozygous BMP15 mutations. Our results bring new insights into the key role played by the BMP15 protein in ovarian function and could contribute to a better understanding of the pathogenesis of women′s fertility disorders. © 2013 Demars et al.
Tosser-Klopp G.,French National Institute for Agricultural Research |
Tosser-Klopp G.,Laboratoire Of Genetique Cellulaire |
Bardou P.,French National Institute for Agricultural Research |
Bardou P.,Laboratoire Of Genetique Cellulaire |
And 63 more authors.
PLoS ONE | Year: 2014
The success of Genome Wide Association Studies in the discovery of sequence variation linked to complex traits in humans has increased interest in high throughput SNP genotyping assays in livestock species. Primary goals are QTL detection and genomic selection. The purpose here was design of a 50-60,000 SNP chip for goats. The success of a moderate density SNP assay depends on reliable bioinformatic SNP detection procedures, the technological success rate of the SNP design, even spacing of SNPs on the genome and selection of Minor Allele Frequencies (MAF) suitable to use in diverse breeds. Through the federation of three SNP discovery projects consolidated as the International Goat Genome Consortium, we have identified approximately twelve million high quality SNP variants in the goat genome stored in a database together with their biological and technical characteristics. These SNPs were identified within and between six breeds (meat, milk and mixed): Alpine, Boer, Creole, Katjang, Saanen and Savanna, comprising a total of 97 animals. Whole genome and Reduced Representation Library sequences were aligned on >10 kb scaffolds of the de novo goat genome assembly. The 60,000 selected SNPs, evenly spaced on the goat genome, were submitted for oligo manufacturing (Illumina, Inc) and published in dbSNP along with flanking sequences and map position on goat assemblies (i.e. scaffolds and pseudo-chromosomes), sheep genome V2 and cattle UMD3.1 assembly. Ten breeds were then used to validate the SNP content and 52,295 loci could be successfully genotyped and used to generate a final cluster file. The combined strategy of using mainly whole genome Next Generation Sequencing and mapping on a contig genome assembly, complemented with Illumina design tools proved to be efficient in producing this GoatSNP50 chip. Advances in use of molecular markers are expected to accelerate goat genomic studies in coming years. Copyright: © 2014 Tosser-Klopp et al.
Fresard L.,French National Institute for Agricultural Research |
Fresard L.,Laboratoire Of Genetique Cellulaire |
Morisson M.,French National Institute for Agricultural Research |
Morisson M.,Laboratoire Of Genetique Cellulaire |
And 6 more authors.
Genetics Selection Evolution | Year: 2013
Little is known about epigenetic mechanisms in birds with the exception of the phenomenon of dosage compensation of sex chromosomes, although such mechanisms could be involved in the phenotypic variability of birds, as in several livestock species. This paper reviews the literature on epigenetic mechanisms that could contribute significantly to trait variability in birds, and compares the results to the existing knowledge of epigenetic mechanisms in mammals. The main issues addressed in this paper are: (1) Does genomic imprinting exist in birds? (2) How does the embryonic environment influence the adult phenotype in avian species? (3) Does the embryonic environment have an impact on phenotypic variability across several successive generations? The potential for epigenetic studies to improve the performance of individual animals through the implementation of limited changes in breeding conditions or the addition of new parameters in selection models is still an open question. © 2013 Frésard et al.; licensee BioMed Central Ltd.
Bonnet A.,French National Institute for Agricultural Research |
Bonnet A.,Laboratoire Of Genetique Cellulaire |
Cabau C.,French National Institute for Agricultural Research |
Bouchez O.,French National Institute for Agricultural Research |
And 12 more authors.
BMC Genomics | Year: 2013
Background: Successful early folliculogenesis is crucial for female reproductive function. It requires appropriate gene specific expression of the different types of ovarian cells at different developmental stages. To date, most gene expression studies on the ovary were conducted in rodents and did not distinguish the type of cell. In mono-ovulating species, few studies have addressed gene expression profiles and mainly concerned human oocytes.Results: We used a laser capture microdissection method combined with RNA-seq technology to explore the transcriptome in oocytes and granulosa cells (GCs) during development of the sheep ovarian follicle. We first documented the expression profile of 15 349 genes, then focused on the 5 129 genes showing differential expression between oocytes and GCs. Enriched functional categories such as oocyte meiotic arrest and GC steroid synthesis reflect two distinct cell fates. We identified the implication of GC signal transduction pathways such as SHH, WNT and RHO GTPase. In addition, signaling pathways (VEGF, NOTCH, IGF1, etc.) and GC transzonal projections suggest the existence of complex cell-cell interactions. Finally, we highlighted several transcription regulators and specifically expressed genes that likely play an important role in early folliculogenesis.Conclusions: To our knowledge, this is the first comprehensive exploration of transcriptomes derived from in vivo oocytes and GCs at key stages in early follicular development in sheep. Collectively, our data advance our understanding of early folliculogenesis in mono-ovulating species and will be a valuable resource for unraveling human ovarian dysfunction such as premature ovarian failure (POF). © 2013 Bonnet et al.; licensee BioMed Central Ltd.
Sallet E.,French National Institute for Agricultural Research |
Sallet E.,French National Center for Scientific Research |
Roux B.,French National Institute for Agricultural Research |
Roux B.,French National Center for Scientific Research |
And 20 more authors.
DNA Research | Year: 2013
The availability of next-generation sequences of transcripts from prokaryotic organisms offers the opportunity to design a new generation of automated genome annotation tools not yet available for prokaryotes. In this work, we designed EuGene-P, the first integrative prokaryotic gene finder tool which combines a variety of high-throughput data, including oriented RNA-Seq data, directly into the prediction process. This enables the automated prediction of coding sequences (CDSs), untranslated regions, transcription start sites (TSSs) and non-coding RNA (ncRNA, sense and antisense) genes. EuGene-P was used to comprehensively and accurately annotate the genome of the nitrogen-fixing bacterium Sinorhizobium meliloti strain 2011, leading to the prediction of 6308 CDSs as well as 1876 ncRNAs. Among them, 1280 appeared as antisense to a CDS, which supports recent findings that antisense transcription activity is widespread in bacteria. Moreover, 4077 TSSs upstream of protein-coding or non-coding genes were precisely mapped providing valuable data for the study of promoter regions. By looking for RpoE2-binding sites upstream of annotated TSSs, we were able to extend the S. meliloti RpoE2 regulon by ~3-fold. Altogether, these observations demonstrate the power of EuGene-P to produce a reliable and high-resolution automatic annotation of prokaryotic genomes. © 2013 © The Author 2013. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.