title: Rice phytochrome-interacting factor-like protein OsPIL1 functions as a key regulator of internode elongation and induces a morphological response to drought stress.
abstract: The mechanisms for plant growth restriction during stress conditions remains unclear. Here, we demonstrate that a phytochrome-interacting factor-like protein, OsPIL1/OsPIL13, acts as a key regulator of reduced internode elongation in rice under drought conditions. The level of OsPIL1 mRNA in rice seedlings grown under nonstressed conditions with light/dark cycles oscillated in a circadian manner with peaks in the middle of the light period. Under drought stress conditions, OsPIL1 expression was inhibited during the light period. We found that OsPIL1 was highly expressed in the node portions of the stem using promoter-glucuronidase analysis. Overexpression of OsPIL1 in transgenic rice plants promoted internode elongation. In contrast, transgenic rice plants with a chimeric repressor resulted in short internode sections. Alteration of internode cell size was observed in OsPIL1 transgenic plants, indicating that differences in cell size cause the change in internode length. Oligoarray analysis revealed OsPIL1 downstream genes, which were enriched for cell wall-related genes responsible for cell elongation. These data suggest that OsPIL1 functions as a key regulatory factor of reduced plant height via cell wall-related genes in response to drought stress. This regulatory system may be important for morphological stress adaptation in rice under drought conditions.
authors.affiliation: Biological Resources and Post-harvest Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Todaka
authors.forename: Kazuo
authors.initials: K
authors.lastname: Nakashima
authors.forename: Kyonoshin
authors.initials: K
authors.lastname: Maruyama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kidokoro
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Osakabe
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ito
authors.forename: Satoko
authors.initials: S
authors.lastname: Matsukura
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Fujita
authors.forename: Kyouko
authors.initials: K
authors.lastname: Yoshiwara
authors.forename: Masaru
authors.initials: M
authors.lastname: Ohme-Takagi
authors.forename: Mikiko
authors.initials: M
authors.lastname: Kojima
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sakakibara
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shinozaki
authors.forename: Kazuko
authors.initials: K
authors.lastname: Yamaguchi-Shinozaki
mesh_terms: D000222:Adaptation, Physiological; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D010834:Phytochrome / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018749:RNA, Plant / Q000096:biosynthesis / Q000235:genetics; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D014157:Transcription Factors; D010834:Phytochrome