title: The 14-3-3 Proteins mu and upsilon influence transition to flowering and early phytochrome response.
abstract: 14-3-3 proteins regulate a diverse set of biological responses but developmental phenotypes associated with 14-3-3 mutations have not been described in plants. Here, physiological and biochemical tests demonstrate interactions between 14-3-3s and the well-established mechanisms that govern light sensing and photoperiodic flowering control. Plants featuring homozygous disruption of 14-3-3 isoforms upsilon and mu display defects in light sensing and/or response. Mutant plants flower late and exhibit long hypocotyls under red light, with little effect under blue or far-red light. The long hypocotyl phenotype is consistent with a role for 14-3-3 upsilon and mu in phytochrome B signaling. Yeast two-hybrid and coimmunoprecipitation assays indicate that 14-3-3 upsilon and mu proteins physically interact with CONSTANS, a central regulator of the photoperiod pathway. Together, these data indicate a potential role for specific 14-3-3 isoforms in affecting photoperiodic flowering via interaction with CONSTANS, possibly as integrators of light signals sensed through the phytochrome system.
authors.affiliation: Plant Molecular and Cellular Biology Program and Horticultural Sciences Department, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Mayfield
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Folta
authors.forename: Anna-Lisa
authors.initials: AL
authors.lastname: Paul
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Ferl
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism / Q000502:physiology*; D017360:Arabidopsis / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000378:metabolism; D001683:Biological Clocks / Q000502:physiology; D003116:Color; D004268:DNA-Binding Proteins / Q000378:metabolism; D035264:Flowers / Q000254:growth & development*; D018546:Hypocotyl / Q000254:growth & development; D016254:Mutagenesis, Insertional; D010641:Phenotype; D017440:Photoperiod; D010834:Phytochrome / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism; D020798:Two-Hybrid System Techniques
chemical_list: D048948:14-3-3 Proteins; D029681:Arabidopsis Proteins; C092776:CONSTANS protein, Arabidopsis; D004268:DNA-Binding Proteins; D014157:Transcription Factors; D010834:Phytochrome