Evolutionary Cytogenomics in Fishes with a focus on Primitive groups

• Grant number: 25/04495-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: October 01, 2025
• End date: July 31, 2030
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Marcelo de Bello Cioffi
• Grantee: Alan Moura de Oliveira
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Fish represent approximately half of all living vertebrates and are an extremely attractive model for the study of several evolutionary questions. In this project, we propose to perform cytogenomic studies on representatives of Sarcopterygii and non-teleostean Actinopterygii (Chondrostei, Cladistia and Holostei); basal groups within the phylogeny of fishes and termed as primitives. These groups constituted the main examples of "living fossils" mentioned by Darwin, a concept that persists in the present day. We specifically aim to i) study the long-term evolution of satellite DNA (satDNA) families; ii) elucidate the mechanisms of chromosome evolution occurring in these lineages, focusing on the Polypteridae family; and iii) obtain chromosome preparations of Piramboia L. paradoxa and perform indexing of its genome to chromosomes via Oligo-FISH. The methodological approaches of this proposal involve i) prospecting, characterization and chromosome mapping of all satellite DNA libraries (Satelitoma) of the target species; ii) chromosome mapping of several classes of repetitive sequences and comparative genomic hybridization (CGH); and iii) design and application of probes based on exclusive oligonucleotides for specific chromosomal regions (Oligo-FISH). Such approaches will enable a better understanding of the mechanisms of genomic and chromosome evolution occurring in fish and vertebrates as a whole. In parallel, the project will facilitate the integration of a network of local and international researchers, equally interested in the topic to be investigated, enabling its execution and the obtaining of promising results for cytogenetics and evolutionary genetics.