PQBP-1/Npw38, a nuclear protein binding to the polyglutamine tract, interacts with U5-15kD/dim1p via the carboxyl-terminal domain.
PQBP-1 was identified as a binding protein to the polyglutamine tract present in various transcription-related factors and causative genes for neurodegenerative disorders. This novel gene contains at least two functional domains, WW domain and carboxyl-terminal domain (CTD), strictly conserved beyond species. Although human PQBP-1 additionally contains the polar amino acid-rich domain by which it binds to the polyglutamine tract, genuine physiological function(s) have not been clarified. In this study, we showed that U5-15kD, human homologue of fission yeast dim1p, is a partner molecule of PQBP-1 binding to CTD. This finding suggests physiological functions of PQBP-1 in splicing, cell cycle, and ubiquitination, through which we can speculate the pathological roles of PQBP-1 in triplet repeat diseases.
Waragai
M
M
Department of Neurology, Graduate School of Medicine, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
Junn
E
E
Kajikawa
M
M
Takeuchi
S
S
Kanazawa
I
I
Shibata
M
M
Mouradian
M M
MM
Okazawa
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins; D006801:Humans; D066298:In Vitro Techniques; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C119246:PQBP1 protein, human; D010455:Peptides; C492272:Pqbp1 protein, mouse; C097188:polyglutamine