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. 1985 Apr;4(4):995–998. doi: 10.1002/j.1460-2075.1985.tb03729.x

Trypanosoma brucei: a surface antigen mRNA is discontinuously transcribed from two distinct chromosomes.

M Guyaux, A W Cornelissen, E Pays, M Steinert, P Borst
PMCID: PMC554290  PMID: 3839457

Abstract

The mRNAs for variant surface glycoproteins (VSGs) and many other proteins in Trypanosoma brucei start with the same sequence of 35 nucleotides, encoded by a separate mini-exon. There are approximately 200 mini-exon genes per trypanosome and these are highly clustered on large chromosomes. We have found two trypanosome variants that express a VSG gene located on a small, 225-kb chromosome. Each gene yields a mRNA containing the 35-nucleotide sequence even though the 225-kb chromosome does not contain a complete mini-exon gene. These results provide a strong support for the hypothesis that transcription of protein-coding genes in trypanosomes is discontinuous.

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