Isolation and identification of molecular markers linked to the W chromosome and analysis of expression of genes related to gonadal sex differentiation in Characidium (Characiformes: Crenuchidae)

• Grant number: 11/15646-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2012
• End date: September 30, 2013
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Lurdes Foresti de Almeida-Toledo
• Grantee: Carolina Pereira Gomes
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The Neotropical region, wihch includes to the countries of Central and South America, such as Brazil, is considered the richest in fish species in the world. With about 4030 species already described, only 62 were described with differentiated sex chromosomes including the genus Characidium, the richest in number of species of the Chrenuchidae family. Most of these species present, the mechanism of sex determination by chromosomes ZZ/ZW (female heterogametic) and carry the Nucleolar Organizer Regions (NORs). Besides that, most studies in the genus are limited to the cytogenetic characterization of sex chromosomes, with unknown molecular mechanisms that trigger the differentiation of males and famales. This project comprises two stages: first, the W chromosome is going to be microdissected, amplified using degenerate primers, cloned into a plasmid and then sequenced. DNA fragments/w-specific genes will in turn be used to develop genetic markers to distinguish PCR genotypic sex. In the second stage, the cDNA of genes encoding the transcription factor dmrt1 and hormone amh (anti-Mullerian hormone), important in the the development of the testes in males, and a gonadal aromatase cyp19a1a, enzyme responsible for converting testosterone to estradiol during ovarian differentiation will be cloned in C. shubart to then have analyzed the expression of mRNA during sexual differentiation by RT-PCR real time and ISH (in situ hybridization).

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

GOMES, Carolina Pereira. Reproduction in Characidium schubarti (Teleostei: Characiformes): analysis of captive breeding and of genes related to sex differentiation (dmrt1, cyp19a1a and amh. 2014. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.