Transcriptome analysis of common snook (Centropomus undecimalis) gonadal development under sex steroid treatments

• Grant number: 19/19874-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: October 01, 2019
• End date: March 31, 2020
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Marine Fishing Resources
• Principal Investigator: Rafael Henrique Nóbrega
• Grantee: Juliana Morena Bonita Ricci
• Supervisor: Manfred Schartl
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Institution abroad: Universität Würzburg, Germany
• Associated to the scholarship: 18/16595-7 - Kisspeptins and its role in reproduction and gonadal development in teleost fish., BP.DR

Abstract

The common snook (Centropomus undecimalis) is a protandrous hermaphrodite fish with high value commercial and potential to finfish farming. One of the bottlenecks in the production of common snook consists in obtaining the captive females. For this reason, a broodstock management in controlling sex ratios by manipulating sex change is necessary. Previous experiment was performed using diet supplemented with sex steroids 17a-methyltestosterone (MT, 60 mg kg-1) and 17b-estradiol (E2, 100mg kg-1) to feed sexually undifferentiated juveniles during 45 days. Treatment with E2 resulted in gonadal morphological remodeling which resembled ovarian differentiation, while treatment with MT showed more advanced signs of testicular differentiation when compared with the control group. In order to explore the molecular mechanisms of sex differentiation, the aim of this project is to compare the gonads transcriptome profiling under different sex steroid treatments using RNA-Seq technology. Transcriptome sequences will be mapped to the reference genome. Transcripts will be quantified as expected read counts and differentially expressed genes (DEGs) among the groups will be detected. The results of this study will provide contributions to sex gonadal development. We expect to find DEGs among the groups and expand our current understanding of developmental pathways and the role of sex-related genes involved in testicular and ovarian differentiation of this species. (AU)