Trans splicing is the physiological process by which mature mRNA molecules are synthesized in trypanosomes, supported by the presence of minRNA that can be released by a debranching extract.
The 5' ends of trypanosome mRNAs consist of an identical sequence of 35 nucleotides. This "mini-exon" sequence is derived from the 5' end of a 137 nucleotide RNA (medRNA). The remainder of each mRNA is derived from a protein-coding exon that is not linked to the mini-exon. We propose that medRNA is spliced in trans to de-novo-initiated transcripts of protein-coding genes. This trans splicing model predicts that the downstream portion of medRNA will be part of a branched structure and then be released as a free product (minRNA). We demonstrate that significant levels of minRNA exist in trypanosome RNA. Furthermore, minRNA can be released from high molecular weight RNA by a HeLa cell S100 "debranching" extract. We conclude that trans splicing is the physiological process by which mature mRNA molecules are synthesized in trypanosomes.
Sutton et al. (1986) studied Trypanosome RNA splicing. Trans splicing is the physiological process by which mature mRNA molecules are synthesized in trypanosomes, supported by the presence of minRNA that can be released by a debranching extract.