Open AccessMammalian DEAD Box Protein Ddx51 Acts in 3′ End Maturation of 28S rRNA by Promoting the Release of U8 snoRNA
Author(s) -
Leena Srivastava,
Yevgeniya R. Lapik,
Minshi Wang,
Dimitri G. Pestov
Publication year - 2010
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.00226-10
Subject(s) - biology , ribosome biogenesis , small nucleolar rna , ribosome , ribosomal rna , eukaryotic small ribosomal subunit , rna helicase a , microbiology and biotechnology , helicase , rna , 5.8s ribosomal rna , ribosomal protein , genetics , non coding rna , gene
Biogenesis of eukaryotic ribosomes requires a number of RNA helicases that drive molecular rearrangements at various points of the assembly pathway. While many ribosome synthesis factors are conserved among all eukaryotes, certain features of ribosome maturation, such as U8 snoRNA-assisted processing of the 5.8S and 28S rRNA precursors, are observed only in metazoan cells. Here, we identify the mammalian DEAD box helicase family member Ddx51 as a novel ribosome synthesis factor and an interacting partner of the nucleolar GTP-binding protein Nog1. Unlike any previously studied yeast helicases, Ddx51 is required for the formation of the 3′ end of 28S rRNA. Ddx51 binds to pre-60S subunit complexes and promotes displacement of U8 snoRNA from pre-rRNA, which is necessary for the removal of the 3′ external transcribed spacer from 28S rRNA and productive downstream processing. These data demonstrate the emergence of a novel factor that facilitates a pre-rRNA processing event specific for higher eukaryotes.