Resumo

SEGURA-VALDEZ, María de Lourdes et al. Intranuclear organization of SR proteins in vertebrates. TIP [online]. 2007, vol.10, n.2, pp.65-69. ISSN 1405-888X.

ln eukaryotes, mRNA is produced as a primary transcript or pre-mRNA which matures in a three step process: 1st) addition of the 7 meG group to end 5'; 2nd) end 3' polyadenylation; 3rd) splicing. For these steps to take place, several factors are required. The cellular organization of such factors corresponds to a distribution called speckled pattern as observed by means of an epifluorescence microscopy. In addition, the morphology of this pattern presents some changes in relation to transcriptional and splicing activities in both culture and tissue cells, in the study reported here, we employed indirect immunofluorescence with monoclonal antibodies against SR proteins. It was shown that the speckled pattern is present in the cells of all vertebrates analyzed. Moreover, the pattern is also present in the hemichordate Balanoglossus. The results suggest that the speckled pattern may be a nuclear characteristic of nonmammal chordates.

Palavras-chave : Nucleus; SR proteins; speckles; splicing; vertebrates.