title: A microarray-based analysis of gametogenesis in two Portuguese populations of the European clam Ruditapes decussatus.
abstract: The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed in four gonadal maturation stages from two different Portuguese wild populations, characterized by different responses to spawning induction when used as progenitors in hatchery. A comparison between the two populations elucidated a specific pathway involved in the recognition signals and binding between the oocyte and components of the sperm plasma membrane. We suggest that this pathway can explain part of the differences in terms of spawning induction success between the two populations. In addition, sexes and reproductive stages were compared and a correlation between mRNA levels and gonadal area was investigated. The lists of differentially expressed genes revealed that sex explains most of the variance in gonadal gene expression. Additionally, genes like Foxl2, vitellogenin, condensing 2, mitotic apparatus protein p62, Cep57, sperm associated antigens 6, 16 and 17, motile sperm domain containing protein 2, sperm surface protein Sp17, sperm flagellar proteins 1 and 2 and dpy-30, were identified as being correlated with the gonad area and therefore supposedly with the number and/or the size of the gametes produced.
authors.affiliation: IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France; IPMA, Olhão, Portugal.
authors.forename: Joana Teixeira
authors.initials: JT
authors.lastname: de Sousa
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Milan
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Bargelloni
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Pauletto
authors.affiliation: IPMA, Olhão, Portugal.
authors.forename: Domitília
authors.initials: D
authors.lastname: Matias
authors.affiliation: IPMA, Olhão, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Joaquim
authors.affiliation: IPMA, Olhão, Portugal.
authors.forename: Ana Margarete
authors.initials: AM
authors.lastname: Matias
authors.affiliation: IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France.
authors.forename: Virgile
authors.initials: V
authors.lastname: Quillien
authors.affiliation: IPMA, Olhão, Portugal.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Leitão
authors.affiliation: IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Huvet
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000145:classification / Q000235:genetics*; D005260:Female; D005718:Gametogenesis / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D056084:Genetic Fitness; D005854:Germ Cells / Q000378:metabolism; D006066:Gonads / Q000254:growth & development / Q000378:metabolism; D008297:Male; D046228:Microarray Analysis; D020411:Oligonucleotide Array Sequence Analysis; D058974:Phylogeography; D011174:Portugal; D012333:RNA, Messenger / Q000235:genetics*; D012098:Reproduction / Q000235:genetics; D012737:Sex Factors
chemical_list: D012333:RNA, Messenger