title: PLASTOCHRON1, a timekeeper of leaf initiation in rice, encodes cytochrome P450.
abstract: During postembryonic development of higher plants, the shoot apical meristem produces lateral organs in a regular spacing (phyllotaxy) and a regular timing (plastochron). Molecular analysis of mutants associated with phyllotaxy and plastochron would greatly increase understanding of the developmental mechanism of plant architecture because phyllotaxy and plastochron are fundamental regulators of plant architecture. pla1 of rice is not only a plastochron mutant showing rapid leaf initiation without affecting phyllotaxy, but also a heterochronic mutant showing ectopic shoot formation in the reproductive phase. Thus, pla1 provides a tool for analyzing the molecular basis of temporal regulation in leaf development. In this work, we isolated the PLA1 gene by map-based cloning. The identified PLA1 gene encodes a cytochrome P450, CYP78A11, which potentially catalyzes substances controlling plant development. PLA1 is expressed in developing leaf primordia, bracts of the panicle, and elongating internodes, but not in the shoot apical meristem. The expression pattern and mutant phenotype suggest that the PLA1 gene acting in developing leaf primordia affects the timing of successive leaf initiation and the termination of vegetative growth.
authors.affiliation: Plant Genetics Laboratory, National Institute of Genetics, Yata 1111, Mishima, Shizuoka 411-8540, Japan.
authors.forename: Kazumaru
authors.initials: K
authors.lastname: Miyoshi
authors.forename: Byung-Ohg
authors.initials: BO
authors.lastname: Ahn
authors.forename: Taiji
authors.initials: T
authors.lastname: Kawakatsu
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Itoh
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nagato
authors.forename: Nori
authors.initials: N
authors.lastname: Kurata
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001683:Biological Clocks / Q000235:genetics; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D017403:In Situ Hybridization; D018519:Meristem / Q000254:growth & development; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D010641:Phenotype; D010802:Phylogeny; D018515:Plant Leaves / Q000254:growth & development
chemical_list: D018744:DNA, Plant; D003577:Cytochrome P-450 Enzyme System