Discontinuous synthesis of mRNA in trypanosomes.
AUTOR(ES)
Kooter, J M
RESUMO
Many trypanosome mRNAs have the same sequence of 35 nucleotides at their 5' end, encoded by a mini-exon located in 1.35-kb tandemly linked repeats. We have analysed nascent and steady-state mini-exon transcripts to determine how the mini-exon sequence is joined to the main part of trypanosome mRNAs. We show here that steady-state RNA from Trypanosoma brucei contains a transcript of 141 nucleotides that starts at the 5' border of the mini-exon. Isolated nuclei transcribe the segment corresponding to the 141 nucleotide RNA at a high rate; transcription of other areas of the 1.35-kb mini-exon repeat is approximately 750-fold lower. We propose that transcription of protein-coding genes in trypanosomes is discontinuous and involves the 141-nucleotide transcript as an intermediate.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=557698Documentos Relacionados
- Selection and Characterization of RNA Interference-Deficient Trypanosomes Impaired in Target mRNA Degradation
- Polygene transcripts are precursors to calmodulin mRNAs in trypanosomes.
- Alpha-amanitin-insensitive transcription of variant surface glycoprotein genes provides further evidence for discontinuous transcription in trypanosomes.
- Telomere conversion in trypanosomes.
- Polycistronic transcripts in trypanosomes and their accumulation during heat shock: evidence for a precursor role in mRNA synthesis.