title: Ef7 encodes an ELF3-like protein and promotes rice flowering by negatively regulating the floral repressor gene Ghd7 under both short- and long-day conditions.
abstract: Much progress has been made in our understanding of photoperiodic flowering of rice and the mechanisms underlying short-day (SD) promotion and long-day (LD) repression of floral induction. In this study, we identified and characterized the Ef7 gene, one of the rice orthologs of Arabidopsis EARLY FLOWERING 3 (ELF3). The ef7 mutant HS276, which was induced by γ-irradiation of the japonica rice cultivar 'Gimbozu', flowers late under both SD and LD conditions. Expression analyses of flowering time-related genes demonstrated that Ef7 negatively regulates the expression of Ghd7, which is a repressor of the photoperiodic control of rice flowering, and consequently up-regulates the expression of the downstream Ehd1 and FT-like genes under both SD and LD conditions. Genetic analyses with a non-functional Ghd7 allele provided further evidence that the delayed flowering of ef7 is mediated through the Ghd7 pathway. The analysis of light-induced expression of Ghd7 revealed that the ef7 mutant was more sensitive to red light than the wild-type plant, but the gate of Ghd7 expression was unchanged. Thus, our results show that Ef7 functions as a floral promoter by repressing Ghd7 expression under both SD and LD conditions.
authors.affiliation: Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Saito
authors.forename: Eri
authors.initials: E
authors.lastname: Ogiso-Tanaka
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Okumoto
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yoshitake
authors.forename: Haruka
authors.initials: H
authors.lastname: Izumi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yokoo
authors.forename: Kazuki
authors.initials: K
authors.lastname: Matsubara
authors.forename: Kiyosumi
authors.initials: K
authors.lastname: Hori
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yano
authors.forename: Hiromo
authors.initials: H
authors.lastname: Inoue
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Tanisaka
mesh_terms: D035264:Flowers / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D017440:Photoperiod; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins