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RESEARCH ARTICLE

Solea senegalensis vasa transcripts: molecular characterisation, tissue distribution and developmental expression profiles

Tiziana Pacchiarini A , Ismael Cross B , Ricardo B. Leite C , Paulo Gavaia C , Juan B. Ortiz-Delgado A , Pedro Pousão-Ferreira D , Laureana Rebordinos B , Carmen Sarasquete A and Elsa Cabrita A E
+ Author Affiliations
- Author Affiliations

A Institute of Marine Science of Andalusia- ICMAN.CSIC, Av Republica Saharaui, 2, 11510 Puerto Real, Cádiz, Spain.

B Laboratory of Genetics, Faculty of Marine Science and Environment, University of Cádiz, Pol. Rio San Pedro, 11510, Puerto Real, Cádiz, Spain.

C Center for Marine Science- CCMAR, University of Algarve, Campus Gambelas, 8000-139 Faro, Portugal.

D IPIMAR, Av. 5 Outubro, 8720-305 Olhão, Portugal.

E Corresponding author. Email: elsa.cabrita@icman.csic.es

Reproduction, Fertility and Development 25(4) 646-660 https://doi.org/10.1071/RD11240
Submitted: 20 September 2011  Accepted: 18 May 2012   Published: 26 July 2012

Abstract

The Vasa protein is an RNA helicase belonging the DEAD (Asp-Glu-Ala-Asp)-box family. The crucial role played by the vasa gene in the germ-cell lineage of both vertebrates and invertebrates has made this gene a useful molecular marker for germinal cells and a useful tool in surrogate broodstock production using primordial germ cell transplantation. With the aim of establishing a novel approach to improving Solea senegalensis broodstock management, the vasa gene in this species was characterised. Four S. senegalensis vasa transcripts were isolated: Ssvasa1, Ssvasa2, Ssvasa3 and Ssvasa4. Their phylogenetic relationship with other vasa homologues was determined confirming the high degree of conservation of this helicase throughout evolution. Our qPCR results showed that S. senegalensis vasa transcripts are prevalently expressed in gonads, with ovary-specific expression for Ssvasa3 and Ssvasa4. During embryonic and larval development, a switch between the longest and the shortest transcripts was observed. While Ssvasa1 and Ssvasa2 were maternally supplied, Ssvasa3 and Ssvasa4 depended on the de novo expression program of the growing juveniles, suggesting that vasa mRNA could be involved in Senegalese sole gonad differentiation. In situ hybridisation and immunohistochemical analysis performed in 150-days after hatching (DAH) larvae showed vasa product expression in the germinal region of early gonads. In our work we demonstrated the usefulness of Ssvasa mRNAs as molecular markers for primordial germ cells and germinal cells during embryonic development, larval ontogenesis and gonad differentiation. Furthermore, our results confirmed the potential of vasa to help investigate germinal cell biotechnology for Senegalese sole reproduction.

Additional keywords: development, ovary, primordial germ cells, testis, vasa expression.


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