A novel conserved RNA-binding domain protein, RBD-1, is essential for ribosome biogenesis.
Synthesis of the ribosomal subunits from pre-rRNA requires a large number of trans-acting proteins and small nucleolar ribonucleoprotein particles to execute base modifications, RNA cleavages, and structural rearrangements. We have characterized a novel protein, RNA-binding domain-1 (RBD-1), that is involved in ribosome biogenesis. This protein contains six consensus RNA-binding domains and is conserved as to sequence, domain organization, and cellular location from yeast to human. RBD-1 is essential in Caenorhabditis elegans. In the dipteran Chironomus tentans, RBD-1 (Ct-RBD-1) binds pre-rRNA in vitro and anti-Ct-RBD-1 antibodies repress pre-rRNA processing in vivo. Ct-RBD-1 is mainly located in the nucleolus in an RNA polymerase I transcription-dependent manner, but it is also present in discrete foci in the interchromatin and in the cytoplasm. In cytoplasmic extracts, 20-30% of Ct-RBD-1 is associated with ribosomes and, preferentially, with the 40S ribosomal subunit. Our data suggest that RBD-1 plays a role in structurally coordinating pre-rRNA during ribosome biogenesis and that this function is conserved in all eukaryotes.
Björk
Petra
P
Department of Molecular Biology and Functional Genomics, Stockholm University, SE-106 91 Stockholm, Sweden.
Baurén
Göran
G
Jin
ShaoBo
S
Tong
Yong-Guang
YG
Bürglin
Thomas R
TR
Hellman
Ulf
U
Wieslander
Lars
L
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002466:Cell Nucleolus / Q000378:metabolism; D002683:Chironomidae / Q000033:anatomy & histology / Q000235:genetics / Q000378:metabolism*; D016384:Consensus Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008938:Mitosis / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D012318:RNA Polymerase I / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012335:RNA, Ribosomal / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D012469:Salivary Glands / Q000166:cytology / Q000378:metabolism; D014158:Transcription, Genetic
D029742:Caenorhabditis elegans Proteins; D005656:Fungal Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; C475128:RBD-1 protein, C elegans; D012335:RNA, Ribosomal; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; D012318:RNA Polymerase I