Isolation and proteomic characterization of human Parvulin-associating preribosomal ribonucleoprotein complexes.
Human parvulin (hParvulin; Par14/EPVH) belongs to the third family of peptidylprolyl cis-trans isomerases that exhibit an enzymatic activity of interconverting the cis-trans conformation of the prolyl peptide bond, and shows sequence similarity to the regulator enzyme for cell cycle transitions, human Pin1. However, the cellular function of hParvulin is entirely unknown. Here, we demonstrate that hParvulin associates with the preribosomal ribonucleoprotein (pre-rRNP) complexes, which contain preribosomal RNAs, at least 26 ribosomal proteins, and 26 trans-acting factors involved in rRNA processing and assembly at an early stage of ribosome biogenesis. Since an amino-terminal domain of hParvulin, which is proposed to be a putative DNA-binding domain, was alone sufficient to associate in principle with the pre-rRNP complexes, the association is probably through protein-RNA interaction. In addition, hParvulin co-precipitated at least 10 proteins not previously known to be involved in ribosome biogenesis. Coincidentally, most of these proteins are implicated in regulation of microtubule assembly or nucleolar reformation during the mitotic phase of the cell. Thus, these results, coupled with the preferential nuclear localization of hParvulin, suggest that hParvulin may be involved in ribosome biogenesis and/or nucleolar re-assembly of mammalian cells.
Fujiyama
Sally
S
Department of Biotechnology, United Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
Yanagida
Mitsuaki
M
Hayano
Toshiya
T
Miura
Yutaka
Y
Isobe
Toshiaki
T
Fujimori
Fumihiro
F
Uchida
Takafumi
T
Takahashi
Nobuhiro
N
D000818:Animals; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D051379:Mice; D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D019696:Peptidylprolyl Isomerase / Q000502:physiology*; D020543:Proteome; D012322:RNA Precursors / Q000378:metabolism; D012261:Ribonucleoproteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D015534:Trans-Activators / Q000302:isolation & purification
D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D020543:Proteome; D012322:RNA Precursors; D012261:Ribonucleoproteins; D012269:Ribosomal Proteins; D015534:Trans-Activators; C000606846:PIN1 protein, human; C000606848:PIN4 protein, human; D019696:Peptidylprolyl Isomerase; C000606850:Pin1 protein, mouse