Comparative cytogenetics among Leporinus friderici and Leporellus vittatus populations (Characiformes, Anostomidae): focus on repetitive DNA elements

By

Dulz, Thais
Lorscheider, Carla
Nascimento, Viviane
Noleto, Rafael
Moreira-Filho, Orlando
Nogaroto, Viviane
Vicari, Marcelo Ricardo

Type

Article

Date of Publication

2019

Original Publication

Comparative cytogenetics : international journal of plant & animal cytogenetics, karyosystematics and molecular systematics

Volume

13

Series / Issue

Issue: 2

Pages

105-120

Subjects

Chromosomal differentiation , karyotype evolution , retrotransposon , ribosomal DNA

Contributed by

Pensoft Publishers

Language

English

Published by

St. Petersburg, Russia [Published] with technical support of Zoological Institute RAS [2007]-

Identifiers

DOI: https://doi.org/10.3897/CompCytogen.v13i2.33764

 

Abstract

Anostomidae are a neotropical fish family rich in number of species. Cytogenetically, they show a conserved karyotype with 2n = 54 chromosomes, although they present intraspecific/interspecific variations in the number and chromosomal location of repetitive DNA sequences. The aim of the present study was to perform a comparative description of the karyotypes of two populations of Leporinusfriderici Bloch, 1794 and three populations of Leporellusvittatus Valenciennes, 1850. We used conventional cytogenetic techniques allied to fluorescence in situ hybridization, using 18S ribosomal DNA (rDNA) and 5S rDNA, a general telomere sequence for vertebrates (TTAGGG)n and retrotransposon (RTE) Rex1 probes. The anostomids in all studied populations presented 2n = 54 chromosomes, with a chromosome formula of 32m + 22sm for L.friderici and 28m + 26sm for L.vittatus. Variations in the number and location of the 5S and 18S rDNA chromosomal sites were observed between L.friderici and L.vittatus populations and species. Accumulation of Rex1 was observed in the terminal region of most chromosomes in all populations, and telomere sequences were located just on all ends of the 54 chromosomes in all populations. The intraspecific and intergeneric chromosomal changes occurred in karyotype differentiation, indicating that minor chromosomal rearrangements had present in anostomid species diversification.