INVESTIGADORES
CAMPO Vanina Andrea
congresos y reuniones científicas
Título:
Role of Trypanosoma cruzi polypirimidine tract binding protein in dicistronic pre-mRNA processing
Autor/es:
CAMPO VA; DE GAUDENZI JG; IZCOVICH R; COLLAERT V; FRASCH, ACC
Lugar:
Mendoza
Reunión:
Congreso; XLVIII Reunión Anual SAIB; 2012
Institución organizadora:
Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular
Resumen:
Trypanosome gene expression clusters are co-transcribed by RNAPII to yield polycistronic pre-mRNAs. During mRNA maturation, polycistrons are processed into monocistrons by two coupled reactions, trans-splicing at the 5′ and polyadenylation at the 3′ end. We have previously observed that alternative trans-splicing can produce dicistronic pre-RNA molecules or transcripts with long 3?untranslated regions. These pre-RNAs should be processed by a post-transcriptional trans-splicing event to produce mature mRNAs. Our hypothesis is that trans-splicing is a regulated process serving as another mechanism for gene expression regulation. We focus in the identification of pre-RNA molecules and the analysis of trans-splicing regulation factors. In this context, we have previously described a dicistronic unit containing coding sequences for two U-rich RNA binding proteins. Now, we found that dicistronic RNAs from parasites transfected with fusion-tagged recombinant constructs are not translated into protein products. Furthermore, DRBD4, a trypanosome homologue of the PTB splicing regulator, is involved in the dicistronic processing. Finally, sequence analysis of a cDNA library obtained from co-immunoprecipitated DRBD4-associated RNAs allowed for the identification of 24 target transcripts, including 15 new putative dicistronic units, most of them coding for hypothetical and RNA-binding proteins.