Stage-specific transcription activator ESB1 regulates monoallelic antigen expression in Trypanosoma brucei.
Nat Microbiol
; 7(8): 1280-1290, 2022 08.
Article
em En
| MEDLINE
| ID: mdl-35879525
ABSTRACT
Variant surface glycoprotein (VSG) coats bloodstream form Trypanosoma brucei parasites, and monoallelic VSG expression underpins the antigenic variation necessary for pathogenicity. One of thousands of VSG genes is transcribed by RNA polymerase I in a singular nuclear structure called the expression site body (ESB), but how monoallelic VSG transcription is achieved remains unclear. Using a localization screen of 153 proteins we found one, ESB-specific protein 1 (ESB1), that localized only to the ESB and is expressed only in VSG-expressing life cycle stages. ESB1 associates with DNA near the active VSG promoter and is necessary for VSG expression, with overexpression activating inactive VSG promoters. Mechanistically, ESB1 is necessary for recruitment of a subset of ESB components, including RNA polymerase I, revealing that the ESB has separately assembled subdomains. Because many trypanosomatid parasites have divergent ESB1 orthologues yet do not undergo antigenic variation, ESB1 probably represents an important class of transcription regulators.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Trypanosoma brucei brucei
Idioma:
En
Revista:
Nat Microbiol
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Reino Unido