title: An active precursor in assembly of yeast nuclear ribonuclease P.
abstract: The RNA-protein subunit assembly of nuclear RNase P was investigated by specific isolation and characterization of the precursor and mature forms of RNase P using an RNA affinity ligand. Pre-RNase P was as active in pre-tRNA cleavage as mature RNase P, although it contained only seven of the nine proteins found in mature RNase P. Pop3p and Rpr2p were not required for maturation of the RPR1 RNA subunit and virtually absent from pre-RNase P, implying that they are dispensable for pre-tRNA substrate recognition and cleavage. The RNase P subunit assembly is likely to occur in the nucleolus, where both precursor and mature forms of RNase P RNA are primarily localized. The results provide insight into assembly of nuclear RNase P, and suggest pre-tRNA substrate recognition is largely determined by the RNA subunit.
authors.affiliation: Department of Biological Chemistry, University of Michigan, Ann Arbor 48109-0606, USA.
authors.forename: Chatchawan
authors.initials: C
authors.lastname: Srisawat
authors.forename: Felicia
authors.initials: F
authors.lastname: Houser-Scott
authors.forename: Edouard
authors.initials: E
authors.lastname: Bertrand
authors.forename: Shaohua
authors.initials: S
authors.lastname: Xiao
authors.forename: Robert H
authors.initials: RH
authors.lastname: Singer
authors.forename: David R
authors.initials: DR
authors.lastname: Engelke
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002466:Cell Nucleolus / Q000378:metabolism; D004722:Endoribonucleases / Q000235:genetics / Q000378:metabolism*; D004792:Enzyme Precursors / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D021122:Protein Subunits; D016337:RNA, Catalytic / Q000235:genetics / Q000378:metabolism*; D012331:RNA, Fungal / Q000378:metabolism; D043262:Ribonuclease P; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D015003:Yeasts / Q000378:metabolism*
chemical_list: D004792:Enzyme Precursors; D021122:Protein Subunits; D016337:RNA, Catalytic; D012331:RNA, Fungal; D012261:Ribonucleoproteins; D029701:Saccharomyces cerevisiae Proteins; D004722:Endoribonucleases; D043262:Ribonuclease P