Rpf2p, an evolutionarily conserved protein, interacts with ribosomal protein L11 and is essential for the processing of 27 SB Pre-rRNA to 25 S rRNA and the 60 S ribosomal subunit assembly in Saccharomyces cerevisiae.
Saccharomyces cerevisiae Rrs1p is a nuclear protein that is essential for the maturation of 25 S rRNA and the 60 S ribosomal subunit assembly. In two-hybrid screening, using RRS1 as bait, we have cloned YKR081c/RPF2. Rpf2p is essential for growth and is mainly localized in the nucleolus. The amino acid sequence of Rpf2p is highly conserved in eukaryotes from yeast to human. Similar to Rrs1p, Rpf2p shows physical interaction with ribosomal protein L11 and appears to associate with preribosomal subunits fairly tightly. Northern, methionine pulse-chase, and sucrose density gradient ultracentrifugation analyses reveal that the depletion of Rpf2p results in a delayed processing of pre-rRNA, a decrease of mature 25 S rRNA, and a shortage of 60 S subunits. An analysis of processing intermediates by primer extension shows that the Rpf2p depletion leads to an accumulation of 27 SB pre-rRNA, suggesting that Rpf2p is required for the processing of 27 SB into 25 S rRNA.
Morita
Daisuke
D
Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-4-4, Higashi-Hiroshima 739-8528, Japan.
Miyoshi
Keita
K
Matsui
Yasushi
Y
Toh-E
Akio
A
Shinkawa
Hidenori
H
Miyakawa
Tokichi
T
Mizuta
Keiko
K
D000483:Alleles; D015152:Blotting, Northern; D015153:Blotting, Western; D002466:Cell Nucleolus / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D012322:RNA Precursors / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism*; D013997:Time Factors; D020798:Two-Hybrid System Techniques
D012322:RNA Precursors; D012335:RNA, Ribosomal; D016601:RNA-Binding Proteins; C451023:RPF2 protein, S cerevisiae; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; C027624:ribosomal protein L11; C065039:RNA, ribosomal, 25S