A conserved stem-loop structure in the 3' untranslated region of procyclin mRNAs regulates expression in Trypanosoma brucei.
Proc Natl Acad Sci U S A
; 91(1): 370-4, 1994 Jan 04.
Article
em En
| MEDLINE
| ID: mdl-8278396
ABSTRACT
African trypanosomes that cycle between mammalian hosts and the tsetse fly vector must be poised to survive in different environments. The control of stage-specific gene expression is undoubtedly one of the keys to successful adaptation, but no regulatory elements have been defined to date. Procyclins (also known as procyclic acidic repetitive proteins) are specifically expressed on the surface of procyclic and epimastigote forms in the fly. Procyclin genes are already transcribed in bloodstream forms, but stable mRNA, and later the protein, are first detected when the parasites begin to differentiate into procyclic forms. We have now identified a region of 16 bases that forms part of a predicted stem-loop structure in the 3' untranslated regions of different procyclin mRNAs; both the sequence and the secondary structure of this 16-mer appear to be required for efficient translation of a reporter gene in procyclic forms. The level of steady-state mRNA, its polyadenylylation, and its distribution in the cell are all unaffected by the presence or absence of this element. Deletion of the 16-mer alone reduces expression more than removal or reversal of the entire 3' untranslated region and flanking region, suggesting that there are additional negative regulatory elements in the same 3' untranslated region.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Trypanosoma brucei brucei
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Glicoproteínas de Membrana
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Glicoproteínas Variantes de Superfície de Trypanosoma
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Regulação da Expressão Gênica
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
1994
Tipo de documento:
Article
País de afiliação:
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