Gonad transcriptome analysis of pearl oyster Pinctada margaritifera: identification of potential sex differentiation and sex determining genes

BMC Genomics

Gilles Le Moullac²  Yannick Gueguen²  Nabila Gaertner-Mazouni⁵  Emeline Lhuillier¹  Christophe Klopp³  Peva Levy²  Arnaud Huvet⁴  Vaihiti Teaniniuraitemoana² 

[1] Present address : GeT-Purpan, GenoToul, UDEAR UMR 1065 CNRS/UPS/U1056 INSERM, CHU PURPAN, Place du Dr Baylac, TSA 40031, 31059 Toulouse Cedex 9, France;Ifremer, UMR 241 EIO, Labex CORAIL, BP 7004, 98719 Taravao, Tahiti, Polynésie Française;INRA, Sigenae, UR875, Auzeville, BP 52627, 31326 Castanet-Tolosan, France;Ifremer, UMR 6539 LEMAR, BP 70, 29280 Plouzané, France;Université de la Polynésie Française, UMR 241 EIO, Labex CORAIL, BP 6570, 98702 Faa’a, Tahiti, Polynésie Française

关键词: Sex determinism;    Differential expression;    Transcriptome;    Gametogenesis;    Pinctada margaritifera;   

Others  :  1216572
DOI  :  10.1186/1471-2164-15-491

 received in 2014-01-23, accepted in 2014-06-13,  发布年份 2014

【 摘 要 】

Background

Black pearl farming is based on culture of the blacklip pearl oyster Pinctada margaritifera (Mollusca, lophotrochozoa), a protandrous hermaphrodite species. At first maturation, all individuals are males. The female sex appears progressively from two years old, which represents a limitation for broodstock conditioning for aquaculture production. In marine mollusks displaying hermaphroditic features, data on sexual determinism and differentiation, including the molecular sex determining cascade, are scarce. To increase genomic resources and identify the molecular mechanisms whereby gene expression may act in the sexual dimorphism of P. margaritifera, we performed gonad transcriptome analysis.

Results

The gonad transcriptome of P. margaritifera was sequenced from several gonadic samples of males and females at different development stages, using a Next-Generation-Sequencing method and RNAseq technology. After Illumina sequencing, assembly and annotation, we obtained 70,147 contigs of which 62.2% shared homologies with existing protein sequences, and 9% showed functional annotation with Gene Ontology terms. Differential expression analysis identified 1,993 differentially expressed contigs between the different categories of gonads. Clustering methods of samples revealed that the sex explained most of the variation in gonad gene expression. K-means clustering of differentially expressed contigs showed 815 and 574 contigs were more expressed in male and female gonads, respectively. The analysis of these contigs revealed the presence of known specific genes coding for proteins involved in sex determinism and/or differentiation, such as dmrt and fem-1 like for males, or foxl2 and vitellogenin for females. The specific gene expression profiles of pmarg-fem1-like, pmarg-dmrt and pmarg-foxl2 in different reproductive stages (undetermined, sexual inversion and regression) suggest that these three genes are potentially involved in the sperm-oocyte switch in P. margaritifera.

Conclusions

The study provides a new transcriptomic tool to study reproduction in hermaphroditic marine mollusks. It identifies sex differentiation and potential sex determining genes in P. margaritifera, a protandrous hermaphrodite species.

【 授权许可】

   
2014 Teaniniuraitemoana et al.; licensee BioMed Central Ltd.

【 图 表 】

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