Table 1.

The physiological functions of FRS-FRF family proteins in Arabidopsis.

Cellular process	Targets	Transcriptional regulation	Reference
Light signal transduction	FHY1/FHL COP1	FHY3/FAR1 (+), HY5 (-) FHY3/FAR1 (+), HY5 (+)	Lin et al., 2007; Li et al., 2010; Huang et al., 2012
Chloroplast division	ARC5	FHY3/FAR1(+), FRS4 (+)	Ouyang et al., 2011; Gao et al., 2013
Chlorophyll biosynthesis Immunity response	HEMB1	FHY3/FAR1 (+), PIF1(-)	Tang et al., 2012; Wang et al., 2016
Myo-inositol synthesis Oxidative response	MIPS1/MIPS2	FHY3/FAR1 (+)	Ma et al., 2016
Starch synthesis	ISA2	FHY3/FAR1 (+)	Ma et al., 2017
Circadian clock Flowering time	ELF4	FHY3/FAR1/HY5 (+), CCA1/LHY (-)	Li et al., 2011
Diurnal growth Flowering time regulation	PIF4 Gl	FRS7 (-), FRS12 (-)	Ritter et al., 2017
Floral development	CLV3 SEP2 STM	FHY3 (-) FHY3 (+) FRF1 (?)	Li et al., 2016; Aguilar-Martinez et al., 2015
Drought stress ABA response	ABI5	FHY3/FAR1 (+)	Tang et al., 2013
Low phosphate response	PHR1	FHY3/FAR1/EIN3 (+), HY5 (-)	Liu Y. et al., 2017

+, positive regulation; -, negative regulation.