title: Bcp1 Is the Nuclear Chaperone of Rpl23 in Saccharomyces cerevisiae.
abstract: Eukaryotic ribosomes are composed of rRNAs and ribosomal proteins. Ribosomal proteins are translated in the cytoplasm and imported into the nucleus for assembly with the rRNAs. It has been shown that chaperones or karyopherins responsible for import can maintain the stability of ribosomal proteins by neutralizing unfavorable positive charges and thus facilitate their transports. Among 79 ribosomal proteins in yeast, only a few are identified with specific chaperones. Besides the classic role in maintaining protein stability, chaperones have additional roles in transport, chaperoning the assembly site, and dissociation of ribosomal proteins from karyopherins. Bcp1 has been shown to be necessary for the export of Mss4, a phosphatidylinositol 4-phosphate 5-kinase, and required for ribosome biogenesis. However, its specific function in ribosome biogenesis has not been described. Here, we show that Bcp1 dissociates Rpl23 from the karyopherins and associates with Rpl23 afterward. Loss of Bcp1 causes instability of Rpl23 and deficiency of 60S subunits. In summary, Bcp1 is a novel 60S biogenesis factor via chaperoning Rpl23 in the nucleus.
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Ya-Han
authors.initials: YH
authors.lastname: Ting
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Ting-Jun
authors.initials: TJ
authors.lastname: Lu
authors.affiliation: the Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas, Austin, Texas 78712, and.
authors.forename: Arlen W
authors.initials: AW
authors.lastname: Johnson
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Jing-Ting
authors.initials: JT
authors.lastname: Shie
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Bo-Ru
authors.initials: BR
authors.lastname: Chen
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.|the Department of Medical Microbiology and Parasitology, Universiti Putra Malaysia, 43400 Selangor, Malaysia.
authors.forename: Suresh
authors.initials: S
authors.lastname: Kumar S
authors.affiliation: From the Department of Agricultural Chemistry, National Taiwan University, 1 Sec. 4, Roosevelt Road, Taipei 10617, Taiwan, kaiyin@ntu.edu.tw.
authors.forename: Kai-Yin
authors.identifier: http://orcid.org/0000-0003-0440-6836
authors.initials: KY
authors.lastname: Lo
mesh_terms: D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism*; D054683:Ribosome Subunits, Large, Eukaryotic / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C477607:Bcp1 protein, S cerevisiae; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor); C489795:MSS4 protein, S cerevisiae
keywords: chaperone; phosphoinositide; protein stability; ribosome; ribosome assembly