YB-1 unwinds mRNA secondary structures in vitro and negatively regulates stress granule assembly in HeLa cells.
Nucleic Acids Res
; 49(17): 10061-10081, 2021 09 27.
Article
em En
| MEDLINE
| ID: mdl-34469566
ABSTRACT
In the absence of the scanning ribosomes that unwind mRNA coding sequences and 5'UTRs, mRNAs are likely to form secondary structures and intermolecular bridges. Intermolecular base pairing of non polysomal mRNAs is involved in stress granule (SG) assembly when the pool of mRNAs freed from ribosomes increases during cellular stress. Here, we unravel the structural mechanisms by which a major partner of dormant mRNAs, YB-1 (YBX1), unwinds mRNA secondary structures without ATP consumption by using its conserved cold-shock domain to destabilize RNA stem/loops and its unstructured C-terminal domain to secure RNA unwinding. At endogenous levels, YB-1 facilitates SG disassembly during arsenite stress recovery. In addition, overexpression of wild-type YB-1 and to a lesser extent unwinding-defective mutants inhibit SG assembly in HeLa cells. Through its mRNA-unwinding activity, YB-1 may thus inhibit SG assembly in cancer cells and package dormant mRNA in an unfolded state, thus preparing mRNAs for translation initiation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Iniciação Traducional da Cadeia Peptídica
/
RNA Mensageiro
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Proteína 1 de Ligação a Y-Box
/
Sequências Repetidas Invertidas
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Grânulos de Estresse
Limite:
Humans
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
França