Characterization of genetic links between two clock-associated genes, GI and PRR5 in the current clock model of Arabidopsis thaliana.
The GI (GIGANTEA) and PRR5 (PSEUDO-RESPONSE REGULATOR 5) genes are crucially implicated in the Arabidopsis circadian clock. We characterized a gi prr5 double loss-of-function mutant for the first time with reference to circadian clock-associated phenotypes. The results of this study revealed the genetic linkages between GI and PRR5 in the control of free running circadian oscillation of gene expression, early photomorphogenesis and flowering time. A mathematical clock model consisting of three interactive transcriptional feedback loops has recently been proposed. The model includes the hypothetical evening Y-TOC1 feedback loop, in which "Y" is suspected to be GI and/or PRR5. This issue was also addressed in this study; perhaps GI and PRR5 are not sufficient to fulfill the Y role.
Laboratory of Molecular Microbiology, School of Agriculture, Nagoya University, Nagoya, Japan.
Hideaki
H
Kawamura
Shogo
S
Ito
Takafumi
T
Yamashino
Yusuke
Y
Niwa
Norihito
N
Nakamichi
Takeshi
T
Mizuno
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001683:Biological Clocks / Q000235:genetics* / Q000502:physiology*; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
D029681:Arabidopsis Proteins; C121183:GI protein, Arabidopsis; C523307:PRR5 protein, Arabidopsis; D014157:Transcription Factors