title: Transcriptional and post-transcriptional control of tubulin gene expression in Trypanosoma cruzi.
abstract: We have shown that tubulin mRNA accumulation is regulated at the transcriptional level during metacyclogenesis of Trypanosoma cruzi, although the contribution of post-transcriptional mechanisms is also indicated. mRNA heterogeneity is not restricted to beta-tubulin, and differential regulation of alpha-tubulin mRNAs is observed during this stage of the parasite's life cycle. Treatment of epimastigotes with the microtubule-depolymerizing agent vinblastine resulted in growth inhibition and morphological alterations. Vinblastine also induced a rise in the pool of free tubulin subunits, concomitant with diminished tubulin synthesis and reduced mRNA levels. Tubulin gene transcription remained unaltered during vinblastine treatment, suggesting post-transcriptional control. These observations are in agreement with the autoregulatory model of tubulin gene expression described for a variety of cell types. We conclude that T. cruzi utilizes transcriptional and post-transcriptional control mechanisms for tubulin gene expression.
authors.affiliation: Instituto de Biofísíca Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil.
authors.forename: T P
authors.initials: TP
authors.lastname: Urményi
authors.forename: F T
authors.initials: FT
authors.lastname: De Castro
authors.forename: J F
authors.initials: JF
authors.lastname: Carvalho
authors.forename: W
authors.initials: W
authors.lastname: De Souza
authors.forename: E
authors.initials: E
authors.lastname: Rondinelli
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D005786:Gene Expression Regulation; D007700:Kinetics; D008854:Microscopy, Electron; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics; D014158:Transcription, Genetic; D014349:Trypanosoma cruzi / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D014404:Tubulin / Q000235:genetics*; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D014404:Tubulin; D014747:Vinblastine