The major mRNA-associated protein YB-1 is a potent 5′ cap-dependent mRNA stabilizer
AUTOR(ES)
Evdokimova, Valentina
FONTE
Oxford University Press
RESUMO
mRNA silencing and storage play an important role in gene expression under diverse circumstances, such as throughout early metazoan development and in response to many types of environmental stress. Here we demonstrate that the major mRNA-associated protein YB-1, also termed p50, is a potent cap-dependent mRNA stabilizer. YB-1 addition or overexpression dramatically increases mRNA stability in vitro and in vivo, whereas YB-1 depletion results in accelerated mRNA decay. The cold shock domain of YB-1 is responsible for the mRNA stabilizing activity, and a blocked mRNA 5′ end is required for YB-1-mediated stabilization. Significantly, exogenously added YB-1 destabilizes the interaction of the cap binding protein, eIF4E, with the mRNA cap structure. Conversely, sequestration of eIF4E from the cap increases the association of endogenous YB-1 with mRNA at or near the cap, and significantly enhances mRNA stability. These data support a model whereby down-regulation of eIF4E activity or increasing the YB-1 mRNA binding activity or concentration in cells activates a general default pathway for mRNA stabilization.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=125650Documentos Relacionados
- Cap-dependent deadenylation of mRNA
- Characterization of the 5′-untranslated region of YB-1 mRNA and autoregulation of translation by YB-1 protein
- Structural organization of mRNA complexes with major core mRNP protein YB-1
- Translation of glucose-regulated protein 78/immunoglobulin heavy-chain binding protein mRNA is increased in poliovirus-infected cells at a time when cap-dependent translation of cellular mRNAs is inhibited.
- CapSelect: a highly sensitive method for 5' CAP-dependent enrichment of full-length cDNA in PCR-mediated analysis of mRNAs.