Variant specific transcripts from the co-transposed segments of variant surface glycoprotein genes in Trypanosoma brucei.
We examined steady-state transcripts from the sequences immediately upstream of the 1 and 11 variant surface glycoprotein (VSG) genes in Trypanosoma brucei of the IsTaR 1 serodeme. These sequences, the co-transposed segment, differ in size and sequence, and produce a variety of variant-specific polyadenylated transcripts. Most, if not all, of these transcripts, some of which may be precursors, contain the spliced leader (SL). Variant specific transcription extends from 5' of the co-transposed segment to 100-400 nucleotides downstream of the major VSG mRNA polyadenylation site. The 1 VSG mRNA has at least 2, and possibly 3, SL addition sites; the major site is 120 nucleotides downstream of the polyadenylation site identified by sequencing a cDNA from the co-transposed segment. Two general models for the production of the co-transposed segment transcripts are discussed.
Scholler
J K
JK
Seattle Biomedical Research Institute, WA 98109-1651.
Aline
R F
RF
Stuart
K D
KD
D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D021382:Protein Sorting Signals / Q000235:genetics; D012313:RNA / Q000235:genetics; D014158:Transcription, Genetic; D014346:Trypanosoma brucei brucei / Q000235:genetics*; D014643:Variant Surface Glycoproteins, Trypanosoma / Q000235:genetics*
D021382:Protein Sorting Signals; D014643:Variant Surface Glycoproteins, Trypanosoma; D012313:RNA; D004247:DNA; D004262:DNA Restriction Enzymes