Premium
Structural basis of G‐tract recognition by hnRNP F: implication for alternative splicing
Author(s) -
Dominguez Cyril,
Fisette JeanFrançois,
Chabot Benoit,
Allain Frédéric
Publication year - 2009
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.23.1_supplement.844.1
Subject(s) - rna , rna splicing , guanosine , rna binding protein , stacking , nucleic acid structure , messenger rna , chemistry , polypyrimidine tract , biology , microbiology and biotechnology , biochemistry , gene , organic chemistry
HnRNP F regulates alternative splicing of many pre‐mRNAs, among which the Bcl‐x pre‐mRNA. HnRNP F contains three quasi RNA recognition motifs (qRRMs) that specifically recognizes Guanosine tract (G‐tract) RNA sequences that are crucial for splice site recognition. We solved the structure of the three qRRMs of HnRNP F in complex with a G‐tract RNA (AGGGAU) by NMR. The structures explain how qRRMs specifically recognize three consecutive guanosines. The RNA binding surface of the qRRM is very different than that of the classical RRM and consists of residues located in three loops and involves aromatic residues stacking the RNA and hydrogen bonds between main‐chain and positively charged side‐chains with the three guanosines. Mutagenesis experiments confirmed the importance of these residues in RNA binding. These structures define a novel RNA recognition mechanism. Our data show that G‐tract RNAs form stable G‐quadruplex structures that are destabilized by hnRNP F. We propose that hnRNP F regulates alternative splicing by modifying the RNA structure. Consistently, we show that single qRRMs of hnRNP F regulate splicing of the Bcl‐x pre‐mRNA with almost the same efficiency as the full‐length protein.