title: Isolation and characterization of the pea cytochrome c oxidase Vb gene.
abstract: Three copies of the gene that encodes cytochrome c oxidase subunit Vb were isolated from the pea (PscoxVb-1, PscoxVb-2, and PscoxVb-3). Northern Blot and reverse transcriptase-PCR analyses suggest that all 3 genes are transcribed in the pea. Each pea coxVb gene has an N-terminal extended sequence that can encode a mitochondrial targeting signal, called a presequence. The localization of green fluorescent proteins fused with the presequence strongly suggests the targeting of pea COXVb proteins to mitochondria. Each pea coxVb gene has 5 intron sites within the coding region. These are similar to Arabidopsis and rice, although the intron lengths vary greatly. A phylogenetic analysis of coxVb suggests the occurrence of gene duplication events during angiosperm evolution. In particular, 2 duplication events might have occurred in legumes, grasses, and Solanaceae. A comparison of amino acid sequences in COXVb or its counterpart shows the conservation of several amino acids within a zinc finger motif. Interestingly, a homology search analysis showed that bacterial protein COG4391 and a mitochondrial complex I 13 kDa subunit also have similar amino acid compositions around this motif. Such similarity might reflect evolutionary relationships among the 3 proteins.
authors.affiliation: Graduate School of Agriculture, Kyoto Prefectural University, Kyoto Prefectural Institute of Agricultural Biotechnology, 74 Oji, Kitainayazuma, Seika, Soraku, Kyoto 619-0244, Japan. nk0103@kab.seika.kyoto.jp
authors.forename: Nakao
authors.initials: N
authors.lastname: Kubo
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Arimura
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tsutsumi
authors.forename: Koh-Ichi
authors.initials: K
authors.lastname: Kadowaki
authors.forename: Masashi
authors.initials: M
authors.lastname: Hirai
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000302:isolation & purification; D003576:Electron Transport Complex IV / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D019143:Evolution, Molecular; D020440:Gene Duplication; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007438:Introns; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D018532:Pisum sativum / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000302:isolation & purification; D021122:Protein Subunits; D017386:Sequence Homology, Amino Acid; D016335:Zinc Fingers
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D021122:Protein Subunits; D049452:Green Fluorescent Proteins; D003576:Electron Transport Complex IV