A stimulatory role for the La-related protein 4B in translation.
RNA
; 16(8): 1488-99, 2010 Aug.
Article
en En
| MEDLINE
| ID: mdl-20573744
ABSTRACT
La-related proteins (LARPs) belong to an evolutionarily conserved family of factors with predicted roles in RNA metabolism. Here, we have analyzed the cellular interactions and function of LARP4B, a thus far uncharacterized member of the LARP family. We show that LARP4B is a cytosolic protein that accumulates upon arsenite treatment in cellular stress granules. Biochemical experiments further uncovered an interaction of LARP4B with the cytosolic poly(A) binding protein 1 (PABPC1) and the receptor for activated C Kinase (RACK1), a component of the 40S ribosomal subunit. Under physiological conditions, LARP4B co-sedimented with polysomes in cellular extracts, suggesting a role in translation. In agreement with this notion, overexpression of LARP4B stimulated protein synthesis, whereas knockdown of the factor by RNA interference impaired translation of a large number of cellular mRNAs. In sum, we identified LARP4B as a stimulatory factor of translation. We speculate that LARP4B exerts its function by bridging mRNA factors of the 3' end with initiating ribosomes.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
ARN Mensajero
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
RNA
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2010
Tipo del documento:
Article