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The actin gene promoter of Trypanosoma brucei.

ABSTRACT: The actin genes of Trypanosoma brucei are transcribed constitutively during the parasite life-cycle, by a polymerase sensitive to alpha-amanitin. The start region of the actin gene transcription unit was mapped by virtue of the accumulation of promoter-proximal transcripts which occurs following moderate UV irradiation. This region, located about 4 kilobases upstream from the genes, was able to direct transient expression of the bacterial Chloramphenicol Acetyl Transferase (CAT) gene in both bloodstream and procyclic forms of the parasite. The essential region of the promoter was defined by deletion, and appeared to be within 600 bp upstream from the putative transcription start site. It does not share significant homology with the other trypanosome promoters described so far (VSG, procyclin, rDNA), which all direct alpha-amanitin resistant transcription.

SUBMITTER: Ben Amar MF

PROVIDER: S-EPMC329038 | biostudies-other | 1991 Nov

REPOSITORIES: biostudies-other

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The actin gene promoter of Trypanosoma brucei.

Ben Amar M F MF Jefferies D D Pays A A Bakalara N N Kendall G G Pays E E

Nucleic acids research 19911101 21

The actin genes of Trypanosoma brucei are transcribed constitutively during the parasite life-cycle, by a polymerase sensitive to alpha-amanitin. The start region of the actin gene transcription unit was mapped by virtue of the accumulation of promoter-proximal transcripts which occurs following moderate UV irradiation. This region, located about 4 kilobases upstream from the genes, was able to direct transient expression of the bacterial Chloramphenicol Acetyl Transferase (CAT) gene in both blo ...[more]

PMID: 1945875

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