Delimiting the Origin of a B Chromosome by FISH Mapping, Chromosome Painting and DNA Sequence Analysis in Astyanax paranae (Teleostei, Characiformes)

Silva, Duilio M. Z. de A. [UNESP]Pansonato-Alves, Jose Carlos [UNESP]Utsunomia, Ricardo [UNESP]Araya-Jaime, Cristian [UNESP]Ruiz-Ruano, Francisco J.Daniel, Sandro Natal [UNESP]Hashimoto, Diogo Teruo [UNESP]Oliveira, Claudio [UNESP]Camacho, Juan Pedro M.Porto-Foresti, Fabio [UNESP]Foresti, Fausto [UNESP]2014-12-032014-12-032014-04-15Plos One. San Francisco: Public Library Science, v. 9, n. 4, 10 p., 2014.1932-6203http://hdl.handle.net/11449/112082Supernumerary (B) chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH) is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism.10engDelimiting the Origin of a B Chromosome by FISH Mapping, Chromosome Painting and DNA Sequence Analysis in Astyanax paranae (Teleostei, Characiformes)Artigo10.1371/journal.pone.0094896WOS:000336922600105Acesso abertoWOS000336922600105.pdf3815338174165832