Artigo
Molecular organization of 5S rDNA in fishes of the genus Brycon
Fecha
2001-10-01Registro en:
Genome. Ottawa: Natl Research Council Canada, v. 44, n. 5, p. 893-902, 2001.
0831-2796
10.1139/gen-44-5-893
WOS:000171015300018
1926863917378909
8858800699425352
0000-0003-4600-0367
0000-0003-3534-974X
Autor
Universidade Estadual Paulista (Unesp)
Dalhousie Univ
Universidade Federal de São Carlos (UFSCar)
Resumen
There are few reports on the genomic organization of 5S rDNA in fish species. To characterize the 5S rDNA nucleotide sequence and chromosomal localization in the Neotropical fishes of the genus Brycon, 5S rDNA copies from seven species were generated by PCR. The nucleotide sequences of the coding region (5S rRNA gene) and the nontranscribed spacer (NTS) were determined, revealing that the 5S rRNA genes were highly conserved, while the NTSs were widely variable among the species analyzed. Moreover, two classes of NTS were detected in each species, characterized by base substitutions and insertions-deletions. Using fluorescence in situ hybridization (FISH), two 5S rDNA chromosome loci that could be related to the two 5S rDNA NTS classes were observed in at least one of the species studied. 5S rDNA sequencing and chromosomal localization permitted the characterization of Brycon spp. and suggest a higher similarity among some of them. The data obtained indicate that the 5S rDNA can be an useful genetic marker for species identification and evolutionary studies.