Polycistronic transcripts in trypanosomes and their accumulation during heat shock: evidence for a precursor role in mRNA synthesis.
AUTOR(ES)
Muhich, M L
RESUMO
Maturation of mRNA precursors in trypanosomes involves an apparent trans splicing event in which a 39-nucleotide miniexon sequence, common to all trypanosome mRNAs, is joined to the 5' end of a protein-coding exon. We demonstrate that the processing machinery responsible for the maturation of tubulin mRNA precursors in Trypanosoma brucei can be disrupted by heat shock. This results in an accumulation of polycistronic RNA species and a decrease in the abundance of branched splicing intermediates. At normal temperatures, tubulin polycistronic transcripts were also detected and were shown in pulse-chase experiments to be abundantly synthesized and very rapidly turned over. These results, combined with results of the heat shock experiments, suggest that these polycistronic transcripts are the precursors of the (monocistronic) tubulin mRNAs of trypanosomes.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=365442Documentos Relacionados
- Effects of cycloheximide on thermotolerance expression, heat shock protein synthesis, and heat shock protein mRNA accumulation in rat fibroblasts.
- Recovery of protein synthesis after heat shock: prior heat treatment affects the ability of cells to translate mRNA.
- Discontinuous synthesis of mRNA in trypanosomes.
- Parvovirus RNA transcripts containing sequences not present in mature mRNA: a method for isolation of putative mRNA precursor sequences.
- Role of procollagen mRNA levels in controlling the rate of procollagen synthesis.