Identification and characterization of satellite DNAs present in the genus Thoropa (Anura, Amphibia)

• Grant number: 18/26507-8
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): March 01, 2019
• Effective date (End): December 31, 2019
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal researcher: Patricia Pasquali Parise Maltempi
• Grantee: Giselle Pessanha Pessoa
• Home Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

The repetitive sequences act in important processes and cellular arrangements, as, for example, in the evolutionary dynamics of the sex chromosomes and in the structuring of centromeric heterochromatin, besides providing relevant information on the speciation and phylogeny of related species. The most represented category of repetitive DNA in the genome is satellite DNA, which has been widely used as a marker in several cytogenetic studies on evolution and biological diversity. In anurans, cytogenetic studies are very scarce, especially considering their great diversity. In Thoropa miliaris (Anura: Cycloramphidae), these data are minimal, and nothing is known about the organization of the repetitive sequences in their genome. After applying the C bandage technique in the T. miliaris chromosomes of the populations of Santa Teresa (ES), Paraty (RJ) and São José do Barreiro (SP), a superabundance of centromeric heterochromatin was observed in the first one in relation to that in the last two populations, possibly indicating an accumulation of satellite DNA that would lead to the genetic isolation of the population of Santa Teresa (ES). It is proposed to characterize and locate, for the first time, satellite DNA sequences in T. miliaris from the population of Santa Teresa (ES) and locate them in their chromosomes. It's proposed, furthermore, to compare their organization with the populations of Paraty (RJ) and São José do Barreiro (SP), permiting to generate data that may help in understanding the genomic organization and, maybe, in future taxonomic studies of the species.