title: The tomato photomorphogenetic mutant, aurea, is deficient in phytochromobilin synthase for phytochrome chromophore biosynthesis.
abstract: The aurea mutants of tomato have been widely used as phytochrome-deficient mutants for photomorphogenetic and photobiological studies. By expressed sequence tag (EST)-based screening of sequence databases, we found a tomato gene that encodes a protein homologous to Arabidopsis HY2 for phytochromobilin synthase catalyzing the last step of phytochrome chromophore biosynthesis. The tomato protein expressed in Escherichia coli showed phytochromobilin synthase activity. The corresponding loci in all aurea mutants tested have nucleotide substitutions, deletions or DNA rearrangements. These results indicate that aurea is a mutant of phytochromobilin synthase in tomato. We also discuss a phylogenetic analysis of phytochromobilin synthases in the bilin reductase family.
authors.affiliation: Graduate School of Biostudies, Kyoto University, Kitashirakawa-oiwake, Sakyo, Kyoto, 606-8502 Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Muramoto
authors.forename: Chitose
authors.initials: C
authors.lastname: Kami
authors.forename: Hideo
authors.initials: H
authors.lastname: Kataoka
authors.forename: Naoko
authors.initials: N
authors.lastname: Iwata
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Linley
authors.forename: Keiko
authors.initials: K
authors.lastname: Mukougawa
authors.forename: Akiho
authors.initials: A
authors.lastname: Yokota
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kohchi
mesh_terms: D000595:Amino Acid Sequence; D019143:Evolution, Molecular; D018551:Solanum lycopersicum / Q000201:enzymology* / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation / Q000502:physiology; D010088:Oxidoreductases / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D010802:Phylogeny; D010834:Phytochrome / Q000235:genetics* / Q000378:metabolism
chemical_list: D010834:Phytochrome; D010088:Oxidoreductases; C071703:phytochromobilin synthase