title: The Arabidopsis RING Domain Protein BOI Inhibits Flowering via CO-dependent and CO-independent Mechanisms.
abstract: BOTRYTIS SUSCEPTIBLE1 INTERACTOR (BOI) and its three homologs (BOIs) are RING domain-containing proteins that repress flowering. Here, we investigated how BOIs repress flowering. Genetic analysis of the boiQ quadruple mutant indicates that BOIs repress flowering mainly through FLOWERING LOCUS T (FT). BOIs repress the expression of FT by CONSTANS (CO)-dependent and -independent mechanisms: in the CO-dependent mechanism, BOIs bind to CO, inhibit the targeting of CO to the FT locus, and thus repress the expression of FT; in the CO-independent mechanism, BOIs target the FT locus via a mechanism that requires DELLAs but not CO. This dual repression of FT makes BOIs strong repressors of flowering in both CO-dependent and CO-independent pathways in Arabidopsis thaliana. Our finding that BOIs inhibit CO targeting further suggests that, in addition to modulating CO mRNA expression and CO protein stability, flowering regulation can also modulate the targeting of CO to FT.
authors: Department of Biological Sciences, KAIST, Daejeon 305-701, Korea.
authors: Khoa Thi
authors: KT
authors: Nguyen
authors: Department of Biological Sciences, KAIST, Daejeon 305-701, Korea.
authors: Jeongmoo
authors: J
authors: Park
authors: Department of Biological Sciences, KAIST, Daejeon 305-701, Korea.
authors: Eunae
authors: E
authors: Park
authors: School of Biological Sciences, Seoul National University, Seoul 151-747, Korea.
authors: Ilha
authors: I
authors: Lee
authors: Department of Biological Sciences, KAIST, Daejeon 305-701, Korea. Electronic address: gchoi@kaist.ac.kr.
authors: Giltsu
authors: G
authors: Choi
mesh_terms: D017360:Arabidopsis / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C482738:BOTRYTIS SUSCEPTIBLE1 protein, Arabidopsis; C092776:CONSTANS protein, Arabidopsis; D004268:DNA-Binding Proteins; C418905:FT protein, Arabidopsis; D012097:Repressor Proteins; D014157:Transcription Factors
keywords: BOI; CO; DELLA; DNA binding; flowering