title: Independent action of ELF3 and phyB to control hypocotyl elongation and flowering time.
abstract: Light regulates various aspects of plant growth, and the photoreceptor phytochrome B (phyB) mediates many responses to red light. In a screen for Arabidopsis mutants with phenotypes similar to those of phyB mutants, we isolated two new elf3 mutants. One has weaker morphological phenotypes than previously identified elf3 alleles, but still abolishes circadian rhythms under continuous light. Like phyB mutants, elf3 mutants have elongated hypocotyls and petioles, flower early, and have defects in the red light response. However, we found that elf3 mutations have an additive interaction with a phyB null mutation, with phyA or hy4 null mutations, or with a PHYB overexpression construct, and that an elf3 mutation does not prevent nuclear localization of phyB. These results suggest that either there is substantial redundancy in phyB and elf3 function, or the two genes regulate distinct signaling pathways.
authors.affiliation: University of North Carolina, Biology Department, CB #3280, Coker Hall, Chapel Hill, North Carolina 27599-3280, USA. jreed@email.unc.edu
authors.forename: J W
authors.initials: JW
authors.lastname: Reed
authors.forename: P
authors.initials: P
authors.lastname: Nagpal
authors.forename: R M
authors.initials: RM
authors.lastname: Bastow
authors.forename: K S
authors.initials: KS
authors.lastname: Solomon
authors.forename: M J
authors.initials: MJ
authors.lastname: Dowson-Day
authors.forename: R P
authors.initials: RP
authors.lastname: Elumalai
authors.forename: A J
authors.initials: AJ
authors.lastname: Millar
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D018546:Hypocotyl / Q000502:physiology*; D009154:Mutation; D010641:Phenotype; D010786:Photoreceptor Cells; D045322:Photosynthetic Reaction Center Complex Proteins; D010834:Phytochrome / Q000235:genetics / Q000502:physiology*; D051939:Phytochrome B; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors
chemical_list: D017931:DNA Primers; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins; D014157:Transcription Factors; D010834:Phytochrome; D051939:Phytochrome B