Cloning and transcriptional analysis of a variant surface glycoprotein gene expression site in Trypanosoma brucei.
The variant surface glycoprotein (VSG) gene expression site in Trypanosoma brucei variant 117a has been mapped to a point about 40 kb upstream from the VSG gene. Sequences upstream from the previously identified [Cully, D.F. et al. (1985) Cell 42, 173-182] expression site associated gene (ESAG-I) have been cloned and a stable 1.3 kb transcript has been localized immediately 5' to ESAG-I. This transcript is in the same orientation and approximately as abundant as the ESAG-I message. A highly conserved region, of which at least 15 copies are present in the genome, has been identified further upstream. A stable transcript corresponding to this region was not detected in variant 117a, but a 1.7 kb transcript was detected in variant 221a. In isolated nuclei, representative sequences from the 117a, expression site were transcribed unidirectionally at similar rates, and transcription was insensitive to alpha-amanitin.
Gibbs
C P
CP
Laboratory of Molecular Parasitology, Rockefeller University, New York, NY 10021-6399.
Cross
G A
GA
D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D004262:DNA Restriction Enzymes; D005786:Gene Expression Regulation; D009693:Nucleic Acid Hybridization; D012313:RNA / Q000032:analysis; D014158:Transcription, Genetic; D014346:Trypanosoma brucei brucei / Q000235:genetics*; D014643:Variant Surface Glycoproteins, Trypanosoma / Q000235:genetics*
D014643:Variant Surface Glycoproteins, Trypanosoma; D012313:RNA; D004247:DNA; D004262:DNA Restriction Enzymes