Cytogenetic analysis of three species of the genus Haemulon (Teleostei: Haemulinae) from Margarita Island, Venezuela.
This paper describes the karyotype analysis of Haemulon aurolineatum, Haemulon bonariensis and Haemulon plumierii, by Giemsa staining, C-banding, Ag-staining and fluorescent in situ hybridization (FISH), to locate the 18S and 5S rRNA genes. Diploid modal count in the three species was 2n = 48 acrocentric elements. Except for pair 24, which exhibited an unmistakable secondary constriction in all three species, it was not possible to classify them as homologous to each other because differences in chromosome size were too slight between adjacent pairs within a size-graded series. Ag-NOR clusters were located in pair 24 in the three species with signal located on the secondary constriction of these chromosomes. C-banding demonstrated that the three species share the same distribution pattern of the constitutive heterochromatin with centromeric heterochromatic blocks in the 23 chromosome pairs and a pericentromeric block in pair 24 which is coincident with the NORs. FISH experiments showed that 18S rDNA sequences were located coincident with the Ag-NOR site in the three species; however, differences in both the number and chromosome distribution of 5S-rDNA cluster were detected among them. Our data suggest that chromosome evolution of Haemulon has been preserved from major changes in the karyotypic macrostructure, whereas microstructural changes have occurred.
Nirchio
Mauro
M
Escuela de Ciencias Aplicadas del Mar, Universidad de Oriente, Boca del Rio, Isla de Margarita, Apartado Postal 147, Venezuela. nirchio@cantv.net
Gaviria
Juan I
JI
Oliveira
Claudio
C
Ferreira
Irani Alves
IA
Martins
Cesar
C
D000818:Animals; D002871:Chromosome Banding; D004275:DNA, Ribosomal / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D010473:Perciformes / Q000235:genetics*; D012337:RNA, Ribosomal, 18S / Q000378:metabolism; D012341:RNA, Ribosomal, 5S / Q000378:metabolism; D013045:Species Specificity; D014687:Venezuela
D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S; D012341:RNA, Ribosomal, 5S