The DEAD-box helicase DDX3 supports the assembly of functional 80S ribosomes.
The DEAD-box helicase DDX3 has suggested functions in innate immunity, mRNA translocation and translation, and it participates in the propagation of assorted viruses. Exploring initially the role of DDX3 in the life cycle of hepatitis C virus, we observed the protein to be involved in translation directed by different viral internal ribosomal entry sites. Extension of these studies revealed a general supportive role of DDX3 in translation initiation. DDX3 was found to interact in an RNA-independent manner with defined components of the translational pre-initiation complex and to specifically associate with newly assembling 80S ribosomes. DDX3 knock down and in vitro reconstitution experiments revealed a significant function of the protein in the formation of 80S translation initiation complexes. Our study implies that DDX3 assists the 60S subunit joining process to assemble functional 80S ribosomes.
Institute of Biochemistry and Biotechnology, Faculty of Life Sciences (NFI), Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06120 Halle/Saale, Germany.
Rene
R
Geissler
Ralph P
RP
Golbik
Sven-Erik
SE
Behrens
D045744:Cell Line, Tumor; D053487:DEAD-box RNA Helicases / Q000378:metabolism*; D039642:Eukaryotic Initiation Factors / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D010442:Peptide Chain Initiation, Translational; D014176:Protein Biosynthesis; D054682:Ribosome Subunits, Small, Eukaryotic / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D020506:Untranslated Regions
D039642:Eukaryotic Initiation Factors; D020506:Untranslated Regions; D053487:DEAD-box RNA Helicases