PQBP-1 (Np/PQ): a polyglutamine tract-binding and nuclear inclusion-forming protein.
Polyglutamine(Q) tract binding protein-1 (PQBP-1) was isolated on the basis of its interaction with polyglutamine tracts and localizes predominantly to the nucleus where it suppresses transcriptional activation by a neuron-specific transcription factor, Brn-2. Its C-terminal domain is highly conserved and binds to a component of the spliceosome. PQBP-1 possesses unique repetitive sequences that may fold as polar zippers. Interestingly, PQBP-1 also forms nuclear inclusion bodies, which are similar to those nucleated by the protein products of polyglutamine disease genes. Furthermore, because PQBP-1 is highly conserved in simple animal metazoans and plants (Caenorhabditis elegans and Arabidopsis), it may perform a basic function in cells. By the same token, disruption of the basic function could be critical to the disease process. Collectively, PQBP-1 might be a candidate molecule involved in the pathology of polyglutamine diseases. In this review, we discuss the structure and function of the PQBP-1 protein, the relevance of its aggregation and possible roles in normal and disease processes.
Okazawa
H
H
Department of Neurology, University of Tokyo, Tokyo, Japan. okazawa-tky@umin.ac.jp
Sudol
M
M
Rich
T
T
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D016923:Cell Death / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins; D006801:Humans; D002479:Inclusion Bodies / Q000378:metabolism*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D010455:Peptides / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D018911:Trinucleotide Repeats
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C119246:PQBP1 protein, human; D010455:Peptides; C097188:polyglutamine