The high kinetic stability of a G-quadruplex limits hnRNP F qRRM3 binding to G-tract RNA.
Nucleic Acids Res
; 41(4): 2505-16, 2013 Feb 01.
Article
em En
| MEDLINE
| ID: mdl-23275549
ABSTRACT
The RNA binding protein heterogeneous nuclear ribonucleoprotein (hnRNP) F is involved in telomeres maintenance and pre-mRNA processing, such as alternative splicing and polyadenylation. It specifically recognizes RNA containing three consecutive guanines (G-tracts) that have the potential to assemble into G-quadruplexes. We have proposed recently that hnRNP F could regulate alternative splicing by remodeling RNA structures, such as G-quadruplexes. However, the exact mechanism of hnRNP F binding to such RNA sequences remains unknown. Here, we have studied the binding of the third RNA binding domain of hnRNP F [quasi-RNA recognition motif 3 (qRRM3)] to G-tract RNA using isothermal titration calorimetry, circular dichroism and nuclear magnetic resonance spectroscopy. Our results show that qRRM3 binds specifically exclusively to single-stranded G-tracts (ssRNA), in contrast to previous reports stating that the G-quadruplex was recognized as well. Furthermore, we demonstrate that the pre-existent ssRNA/G-quadruplex equilibrium slows down the formation of the protein-ssRNA complex. Based on in vitro transcription assays, we show that the rate of the protein-RNA complex formation is faster than that of the G-quadruplex. We propose a model according to which hnRNP F could bind RNA co-transcriptionally and prevents G-quadruplex formation.
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Base de dados:
MEDLINE
Assunto principal:
RNA
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Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H
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Quadruplex G
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Guanina
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
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