title: OsIAA13-mediated auxin signaling is involved in lateral root initiation in rice.
abstract: The plant hormone auxin is essential for root formation. After auxin perception, transmission of the auxin signal progresses through the degradation of Aux/IAA proteins. In this study, we newly isolated and characterized a rice gain-of-function mutant, Osiaa13, containing a single amino acid substitution in the core sequence required for the degradation of the OsIAA13 protein. The Osiaa13 mutant displayed typical auxin-related phenotypes: the number of lateral roots was significantly reduced and the root gravitropic response was defective. Osiaa13 mutants also exhibited altered GUS staining controlled by the DR5 promoter in lateral root initiation sites. Furthermore, expression levels of several genes that might be associated with lateral root initiation were altered in Osiaa13. Taken together, our results indicate that OsIAA13 is involved in auxin signaling and controls the expression of genes that are required for lateral root initiation in rice.
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan. kitomi.yuka@d.mbox.nagoya-u.ac.jp
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kitomi
authors.forename: Hiroki
authors.initials: H
authors.lastname: Inahashi
authors.forename: Hinako
authors.initials: H
authors.lastname: Takehisa
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Sato
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Inukai
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D007210:Indoleacetic Acids / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics
chemical_list: D007210:Indoleacetic Acids; D010940:Plant Proteins