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The helicase protein DHX29 promotes translation initiation, cell proliferation, and tumorigenesis.

ABSTRACT: Translational control plays an important role in cell growth and tumorigenesis. Cap-dependent translation initiation of mammalian mRNAs with structured 5'UTRs requires the DExH-box protein, DHX29, in vitro. Here we show that DHX29 is important for translation in vivo. Down-regulation of DHX29 leads to impaired translation, resulting in disassembly of polysomes and accumulation of mRNA-free 80S monomers. DHX29 depletion also impedes cancer cell growth in culture and in xenografts. Thus, DHX29 is a bona fide translation initiation factor that potentially can be exploited as a target to inhibit cancer cell growth.

SUBMITTER: Parsyan A

PROVIDER: S-EPMC2799747 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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The helicase protein DHX29 promotes translation initiation, cell proliferation, and tumorigenesis.

Parsyan Armen A Shahbazian David D Martineau Yvan Y Petroulakis Emmanuel E Alain Tommy T Larsson Ola O Mathonnet Geraldine G Tettweiler Gritta G Hellen Christopher U CU Pestova Tatyana V TV Svitkin Yuri V YV Sonenberg Nahum N

Proceedings of the National Academy of Sciences of the United States of America 20091211 52

Translational control plays an important role in cell growth and tumorigenesis. Cap-dependent translation initiation of mammalian mRNAs with structured 5'UTRs requires the DExH-box protein, DHX29, in vitro. Here we show that DHX29 is important for translation in vivo. Down-regulation of DHX29 leads to impaired translation, resulting in disassembly of polysomes and accumulation of mRNA-free 80S monomers. DHX29 depletion also impedes cancer cell growth in culture and in xenografts. Thus, DHX29 is ...[more]

PMID: 20018725

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