RNA helicase DDX19 stabilizes ribosomal elongation and termination complexes.
The human DEAD-box RNA-helicase DDX19 functions in mRNA export through the nuclear pore complex. The yeast homolog of this protein, Dbp5, has been reported to participate in translation termination. Using a reconstituted mammalian in vitro translation system, we show that the human protein DDX19 is also important for translation termination. It is associated with the fraction of translating ribosomes. We show that DDX19 interacts with pre-termination complexes (preTCs) in a nucleotide-dependent manner. Furthermore, DDX19 increases the efficiency of termination complex (TC) formation and the peptide release in the presence of eukaryotic release factors. Using the eRF1(AGQ) mutant protein or a non-hydrolysable analog of GTP to inhibit subsequent peptidyl-tRNA hydrolysis, we reveal that the activation of translation termination by DDX19 occurs during the stop codon recognition. This activation is a result of DDX19 binding to preTC and a concomitant stabilization of terminating ribosomes. Moreover, we show that DDX19 stabilizes ribosome complexes with translation elongation factors eEF1 and eEF2. Taken together, our findings reveal that the human RNA helicase DDX19 actively participates in protein biosynthesis.
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.
Tatiana
T
Mikhailova
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.
Ekaterina
E
Shuvalova
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.|Faculty of Bioengineering and Bioinformatics, M.V. Lomonosov Moscow State University, Moscow, Russia
Alexander
A
Ivanov
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.|Faculty of Bioengineering and Bioinformatics, M.V. Lomonosov Moscow State University, Moscow, Russia
Denis
D
Susorov
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.
Alexey
A
Shuvalov
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.|Institute of Higher Nervous Activity and Neurophysiology, The Russian Academy of Sciences, Moscow, Russia
Peter M
PM
Kolosov
Engelhardt Institute of Molecular Biology, The Russian Academy of Sciences, Moscow, Russia.
Elena
E
Alkalaeva
D018388:Codon, Terminator; D053487:DEAD-box RNA Helicases / Q000235:genetics / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D009154:Mutation; D029543:Nucleocytoplasmic Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010441:Peptide Chain Elongation, Translational / Q000502:physiology*; D010443:Peptide Chain Termination, Translational / Q000502:physiology*; D020648:Peptide Elongation Factor 1 / Q000378:metabolism; D020652:Peptide Elongation Factor 2 / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism
D018388:Codon, Terminator; D029543:Nucleocytoplasmic Transport Proteins; D020648:Peptide Elongation Factor 1; D020652:Peptide Elongation Factor 2; D012346:RNA, Transfer, Amino Acyl; D029701:Saccharomyces cerevisiae Proteins; C019037:tRNA, peptidyl-; C492382:DBP5 protein, S cerevisiae; C121148:DDX19B protein, human; D053487:DEAD-box RNA Helicases