Bardella, Vanessa Bellini [UNESP]de Souza, Rosana Silistino [UNESP]Barrera San Martin, Juca AbramoTardeli de Jesus Andrade, Celia GuadalupeLaforga Vanzela, Andre LuisVilela de Azeredo-Oliveira, Maria Tercilia [UNESP]2014-05-202014-05-202012-12-01Cell Biology International. London: Portland Press Ltd, v. 36, n. 12, p. 1287-1291, 2012.1065-6995http://hdl.handle.net/11449/21557Cytogenetic studies in triatomines have described the occurrence of holokinetic chromosomes, heterochromatin distribution and the location of rDNA (ribosomal DNA) sites, but few aspects of nuclear organization in this group have been discussed. We have focused on ultrastructural and cytogenetic features and differences in cystic cells of seminiferous tubules between five species of Triatoma. Cystic cells showed evidence of polyploidy events and heterochromatic blocks appeared predominantly in the central region of the nuclei. Cytogenetic analyses showed that there was variation in chromocenter number between species, and that the central regions were AT-rich [DAPI(+) (4',6-diamidino-2-phenylindole(+))], whereas the periphery was CG-rich (CMA(+)). Another characteristic was the distribution of 45S rDNA, which differed according to the chromosomal location of this sequence. In all we have compared aspects of nuclear organization, polyploidy, heterochromatin, rDNA site distribution and methylation levels, as well as the relationships between five species of Triatoma from a cystic cell perspective.1287-1291enganti-5-methylcytosineHeterochromatinTEMpolyploidyrDNATriatominesArtigo10.1042/CBI20120064WOS:000311144500024Acesso restrito