Back to Search Start Over

Structural basis of nucleic acid binding by Nicotiana tabacum glycine-rich RNA-binding protein: implications for its RNA chaperone function.

Authors :
Khan F
Daniëls MA
Folkers GE
Boelens R
Saqlan Naqvi SM
van Ingen H
Source :
Nucleic acids research [Nucleic Acids Res] 2014 Jul; Vol. 42 (13), pp. 8705-18. Date of Electronic Publication: 2014 Jun 23.
Publication Year :
2014

Abstract

Glycine-rich RNA-binding proteins (GR-RBPs) are involved in cold shock response of plants as RNA chaperones facilitating mRNA transport, splicing and translation. GR-RBPs are bipartite proteins containing a RNA recognition motif (RRM) followed by a glycine-rich region. Here, we studied the structural basis of nucleic acid binding of full-length Nicotiana tabacum GR-RBP1. NMR studies of NtGR-RBP1 show that the glycine-rich domain, while intrinsically disordered, is responsible for mediating self-association by transient interactions with its RRM domain (NtRRM). Both NtGR-RBP1 and NtRRM bind specifically and with low micromolar affinity to RNA and single-stranded DNA. The solution structure of NtRRM shows that it is a canonical RRM domain. A HADDOCK model of the NtRRM-RNA complex, based on NMR chemical shift and NOE data, shows that nucleic acid binding results from a combination of stacking and electrostatic interactions with conserved RRM residues. Finally, DNA melting experiments demonstrate that NtGR-RBP1 is more efficient in melting CTG containing nucleic acids than isolated NtRRM. Together, our study supports the model that self-association of GR-RBPs by the glycine-rich region results in cooperative unfolding of non-native substrate structures, thereby enhancing its chaperone function.<br /> (© The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Details

Language :
English
ISSN :
1362-4962
Volume :
42
Issue :
13
Database :
MEDLINE
Journal :
Nucleic acids research
Publication Type :
Academic Journal
Accession number :
24957607
Full Text :
https://doi.org/10.1093/nar/gku468