Dbp6p is an essential putative ATP-dependent RNA helicase required for 60S-ribosomal-subunit assembly in Saccharomyces cerevisiae.
A previously uncharacterized Saccharomyces cerevisiae open reading frame, YNR038W, was analyzed in the context of the European Functional Analysis Network. YNR038W encodes a putative ATP-dependent RNA helicase of the DEAD-box protein family and was therefore named DBP6 (DEAD-box protein 6). Dbp6p is essential for cell viability. In vivo depletion of Dbp6p results in a deficit in 60S ribosomal subunits and the appearance of half-mer polysomes. Pulse-chase labeling of pre-rRNA and steady-state analysis of pre-rRNA and mature rRNA by Northern hybridization and primer extension show that Dbp6p depletion leads to decreased production of the 27S and 7S precursors, resulting in a depletion of the mature 25S and 5.8S rRNAs. Furthermore, hemagglutinin epitope-tagged Dbp6p is detected exclusively within the nucleolus. We propose that Dbp6p is required for the proper assembly of preribosomal particles during the biogenesis of 60S ribosomal subunits, probably by acting as an rRNA helicase.
Kressler
D
D
Département de Biochimie Médicale, Centre Médical Universitaire, Université de Genève, Geneva, Switzerland. dieter.kressler@medecine.unige.ch
de la Cruz
J
J
Rojo
M
M
Linder
P
P
D000595:Amino Acid Sequence; D002466:Cell Nucleolus / Q000378:metabolism; D002470:Cell Survival; D053487:DEAD-box RNA Helicases; D019084:Fluorescent Antibody Technique, Indirect; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D010641:Phenotype; D011518:Proto-Oncogene Proteins; D012316:RNA Nucleotidyltransferases / Q000737:chemistry / Q000502:physiology*; D012322:RNA Precursors / Q000378:metabolism; D012331:RNA, Fungal / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism*; D012340:RNA, Ribosomal, 5.8S / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins
D011518:Proto-Oncogene Proteins; D012322:RNA Precursors; D012331:RNA, Fungal; D012335:RNA, Ribosomal; D012340:RNA, Ribosomal, 5.8S; D029701:Saccharomyces cerevisiae Proteins; C065039:RNA, ribosomal, 25S; D012316:RNA Nucleotidyltransferases; C490617:DBP6 protein, S cerevisiae; D053487:DEAD-box RNA Helicases