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Reset / entrainment mechanism. Biological clock. An innate mechanism in living organisms that controls the periodicity or rhythm of various physiological functions or activities. Circadian rhythm Circadian: circa(around)+dies(day) Ultradian rhythm Infradian rhythm.
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Reset / entrainment mechanism Biological clock An innate mechanism in living organisms that controls the periodicity or rhythm of various physiological functions or activities. • Circadian rhythm • Circadian: circa(around)+dies(day) • Ultradian rhythm • Infradian rhythm Internal biological clock + change of environment
Clock-associated genes • CCA1 • LHY • FKF1 • ZTL • Environments • Temperature • Light • Period • wave Relationship clock-associated genes and the photoreceptors
ELF3 Encodes a Circadian Clock-Regulated Nuclear Protein That Functions in an Arabidopsis PHYB Signal Transduction Pathway
elf3-1 elf3-1:cosmid E11 wild(C) elf3-1:cosmid B8 SD LD SD LD elf3 • Defective in light perception or light-mediated signal transduction • Defective in circadian rhythm responses
Two types of photoreceptor • Five red/far-red light-absorbing phytochromes • Phytochrome A[PHYA], PHYB, PHYC, PHYD, and PHYE • Two blue/UV-A light-absorbing cryptochromes • CRY1 and CRY2
ELF3 • novel 695 amino acid protein • without any significant homology to proteins of known function • glutamine/threonine-rich sequence and nuclear localization signal in the C-terminal region transcription factor
Fig 1-A. Sequence comparison of ELF3 and putative ELF3 homologs Arabidopsis Cardamine tomato rice maize ELF3 function may be conserved between dicots and monocots.
Fig 2. Accumulation of the ELF3 protein is regulated by light and the circadian clock.
Fig 3-1. ELF3 and PHYB proteins interaction in the Yeast Tow-Hybrid System
Fig 3-2. ELF3 and PHYB proteins interaction in Vitro PHYB-ELF3 interaction in vivo could regulate aspects of PHYB-mediated photomorphogenesis
Fig 4-A. Hypocotyl length of seedlings grown under dark, white, red, and far-red light condition.
Fig 4-B Flowering time for wild type and mutant plants under LD or SD growth conditions.
Fig 5. Genetic interactions of the ELF3 overexpression(ELF3-OX) line with the phyB mutation