title: OsPAA2, a distinct alpha 1 subunit gene for the 20S proteasome in rice (Oryza sativa L.).
abstract: The 20S proteasome is the proteolytic complex that is involved in removing abnormal proteins and other diverse biological functions. The 20S proteasome is constituted of 28 subunits arranged in four rings of seven subunits, and exists as a hollow cylinder. The two outer rings and the two inner rings are composed of seven different alpha and beta type subunits, respectively, giving an alpha 7 beta 7 beta 7 alpha 7 structure. We previously reported the primary structures of the 14 proteasomal subunit subfamilies in rice (Oryza sativa), representing the first set for all the subfamilies from monocot. In this study, a distinct cDNA sequence encoding the alpha1 subunit, OsPAA2, was identified. The amino acid sequence similarity between the two rice alpha1 subunits was as low as 59.6%, contrasting with those between paralogs of Arabidopsis proteasome subunit genes. The expression pattern of the OsPAA2 gene was different from that of another alpha1 gene, OsPAA1. These data suggest that OsPAA2 might play a distinct role from that of OsPAA1 in the 20S proteasome complex.
authors.affiliation: Kihara Institute for Biological Research and Graduate School of Integrated Science, Yokohama City University, Maioka 641-12, Totsuka-ku, Yokohama 244-0813, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Oguchi
authors.forename: H
authors.initials: H
authors.lastname: Sassa
authors.forename: H
authors.initials: H
authors.lastname: Hirano
mesh_terms: D000595:Amino Acid Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D003546:Cysteine Endopeptidases / Q000235:genetics*; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics*; D012275:Oryza / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics*; D046988:Proteasome Endopeptidase Complex; D021122:Protein Subunits; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D009097:Multienzyme Complexes; D010940:Plant Proteins; D021122:Protein Subunits; D012333:RNA, Messenger; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex