A DEAD-box protein functions as an ATP-dependent RNA chaperone in group I intron splicing.
The Neurospora crassa CYT-18 protein, the mitochondrial tyrosyl-tRNA synthetase, functions in splicing group I introns by inducing formation of the catalytically active RNA structure. Here, we identified a DEAD-box protein (CYT-19) that functions in concert with CYT-18 to promote group I intron splicing in vivo and vitro. CYT-19 does not bind specifically to group I intron RNAs and instead functions as an ATP-dependent RNA chaperone to destabilize nonnative RNA structures that constitute kinetic traps in the CYT-18-assisted RNA-folding pathway. Our results demonstrate that a DExH/D-box protein has a specific, physiologically relevant chaperone function in the folding of a natural RNA substrate.
Mohr
Sabine
S
Institute for Cellular and Molecular Biology, Department of Chemistry and Biochemistry, Section of Molecular Genetics and Microbiology, School of Biological Sciences, University of Texas at Austin, 78712, USA.
Stryker
John M
JM
Lambowitz
Alan M
AM
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism*; D017398:Alternative Splicing; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004305:Dose-Response Relationship, Drug; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015151:Immunoblotting; D007438:Introns; D007700:Kinetics; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D009492:Neurospora crassa / Q000235:genetics*; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D010641:Phenotype; D012313:RNA / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors
D005656:Fungal Proteins; D012313:RNA; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases