Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae)
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
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Data(s) |
20/05/2014
20/05/2014
25/07/2011
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Resumo |
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Background: The Characidium (a Neotropical fish group) have a conserved diploid number (2n = 50), but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR). In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography.Results: A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location.Conclusions: The results from dual-color fluorescence in situ hybridization (dual-color FISH) using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish. |
Formato |
8 |
Identificador |
http://dx.doi.org/10.1186/1471-2156-12-65 Bmc Genetics. London: Biomed Central Ltd., v. 12, p. 8, 2011. 1471-2156 http://hdl.handle.net/11449/18734 10.1186/1471-2156-12-65 WOS:000294203600001 WOS000294203600001.pdf |
Idioma(s) |
eng |
Publicador |
Biomed Central Ltd. |
Relação |
BMC Genetics |
Direitos |
openAccess |
Tipo |
info:eu-repo/semantics/article |