Transcription rate modulation through the Trypanosoma cruzi life cycle occurs in parallel with changes in nuclear organisation

Transcription rate modulation through the Trypanosoma cruzi life cycle occurs in parallel with changes in nuclear organisation

Autor Elias, MCQB Google Scholar
Marques-Porto, R. Google Scholar
Freymuller, E. Google Scholar
Schenkman, S. Google Scholar
Instituição Universidade Federal de São Paulo (UNIFESP)
Resumo In trypanosomes transcription occurs as large polycistronic units, with trans-splicing and polyadenylation generating each individual mRNA. There are no defined RNA. polymerase II promoters and mRNA stabilisation is most likely the process controlling levels of differentially expressed mRNAs, since no selective modulation of gene activity has even been reported at the transcriptional level. Here, we show a large decrease in the transcription rates by RNA polymerases I and II when proliferative forms of Trypanosoma cruzi (epimastigotes and amastigotes) transform into non-proliferative and infective forms (trypomastigotes). We also show that these changes in transcription occur in parallel with modifications in the nuclear structure. While nuclei of proliferative forms are round, contain small amounts of peripheral heterochromatin and a large nucleolus, nuclei of trypomastigotes are elongated, the nucleolus disappears and the heterochromatin occupies most of the nuclear compartment. the decrease in the transcription parallels the nucleolus disassembly, as seen by the dispersion of nucleolar antigens. As T. cruzi cycles continuously through proliferative and infective forms, the molecular mechanisms involved in the control of nuclear organisation and chromatin remodelling can be revealed by this system. (C) 2001 Elsevier Science B.V. All rights reserved.
Palavra-chave nucleolus
transcription
Trypanosoma cruzi
nucleus organisation
Idioma Inglês
Data de publicação 2001-01-15
Publicado em Molecular and Biochemical Parasitology. Amsterdam: Elsevier B.V., v. 112, n. 1, p. 79-90, 2001.
ISSN 0166-6851 (Sherpa/Romeo, fator de impacto)
Publicador Elsevier B.V.
Extensão 79-90
Fonte http://dx.doi.org/10.1016/S0166-6851(00)00349-2
Direito de acesso Acesso restrito
Tipo Artigo
Web of Science WOS:000167033100009
Endereço permanente http://repositorio.unifesp.br/handle/11600/26474

Exibir registro completo




Arquivo

Arquivo Tamanho Formato Visualização

Não existem arquivos associados a este item.

Este item está nas seguintes coleções

Buscar


Navegar

Minha conta