Special Sm core complex functions in assembly of the U2 small nuclear ribonucleoprotein of Trypanosoma brucei.
Eukaryot Cell
; 8(8): 1228-34, 2009 Aug.
Article
en En
| MEDLINE
| ID: mdl-19542313
The processing of polycistronic pre-mRNAs in trypanosomes requires the spliceosomal small ribonucleoprotein complexes (snRNPs) U1, U2, U4/U6, U5, and SL, each of which contains a core of seven Sm proteins. Recently we reported the first evidence for a core variation in spliceosomal snRNPs; specifically, in the trypanosome U2 snRNP, two of the canonical Sm proteins, SmB and SmD3, are replaced by two U2-specific Sm proteins, Sm15K and Sm16.5K. Here we identify the U2-specific, nuclear-localized U2B'' protein from Trypanosoma brucei. U2B'' interacts with a second U2 snRNP protein, U2-40K (U2A'), which in turn contacts the U2-specific Sm16.5K/15K subcomplex. Together they form a high-affinity, U2-specific binding complex. This trypanosome-specific assembly differs from the mammalian system and provides a functional role for the Sm core variation found in the trypanosomal U2 snRNP.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Trypanosoma brucei brucei
/
Proteínas Protozoarias
/
Ribonucleoproteína Nuclear Pequeña U2
/
Proteínas Nucleares snRNP
Límite:
Animals
Idioma:
En
Revista:
Eukaryot Cell
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2009
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos