FKF1 F-box protein mediates cyclic degradation of a repressor of CONSTANS in Arabidopsis.
The temporal control of CONSTANS (CO) expression and activity is a key mechanism in photoperiodic flowering in Arabidopsis. FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 (FKF1) protein regulates CO transcription, although the molecular mechanism is unknown. We demonstrate here that FKF1 controls the stability of a Dof transcription factor, CYCLING DOF FACTOR 1 (CDF1). FKF1 physically interacts with CDF1, and CDF1 protein is more stable in fkf1 mutants. Plants with elevated levels of CDF1 flower late and have reduced expression of CO. CDF1 and CO are expressed in the same tissues, and CDF1 binds to the CO promoter. Thus, FKF1 controls daily CO expression in part by degrading CDF1, a repressor of CO transcription.
Department of Cell Biology, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Takato
T
Imaizumi
Thomas F
TF
Schultz
Frank G
FG
Harmon
Lindsey A
LA
Ho
Steve A
SA
Kay
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D035264:Flowers / Q000254:growth & development; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D030821:Plants, Genetically Modified; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D014158:Transcription, Genetic
D029681:Arabidopsis Proteins; C502170:CDF1 protein, Arabidopsis; C092776:CONSTANS protein, Arabidopsis; D004268:DNA-Binding Proteins; C410504:FKF1 protein, Arabidopsis; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D046988:Proteasome Endopeptidase Complex