Basic and molecular cytogenetic in Bergiaria westermanni (Siluriformes, Pimelodidae), with emphasis on B chromosomes

• Grant number: 15/04453-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2015
• End date: December 31, 2016
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Orlando Moreira Filho
• Grantee: Geovana de Cassia Malimpensa
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The order Siluriformes comprises the second largest group of fish in South America, with more than 3,000 species, of which 109 belong to the family Pimelodidae. The diploid number in Pimelodidae ranges from 2n = 50 in Callophysus macropterus, to 2n = 60 chromosomes in Conorhyncus conirostris. The Bergiaria genus (Pimelodidae) includes two species: Bergiaria westermanni and Bergiaria platana. Among the Pimelodidae, some species already have descriptions of B chromosomes in their karyotype, including Bergiaria westermanni. In this study will be performed classical cytogenetic techniques (conventional Giemsa staining, C-banding and silver nitrate impregnation - Ag-NOR) and molecular cytogenetic techniques (fluorescence in situ hybridization with probes of 18S and 5S rDNAs, (GATA)n and telomeric sequences, and H1 and H4 histones) in Bergiaria westermanni from the basin of the São Francisco river, aiming at the characterization of this species from the perspective of different chromosomal markers, with particular interest in B chromosomes, their constitution and frequency in the population. The results will be compared to the available data in the literature, in order to increase the knowledge of B chromosomes in this species and chromosomal evolution of Pimelodidae family.