Table 1. Phosphorylation site-mutants of plant phytochromes included in this study

Phytochromes	Domain1)	Mutant2)	Plant species	Activity3)	References
phyA	NTE	S8A	Avena sativa	+	[17]
		S18A
		S8/18A
	Hinge	S599A	Avena sativa	+	[16]
		S590A/S602A	Arabidopsis thaliana	–	[18]
		S590A/T593A/S602A		–
		S590D/T593D/S602D		–
phyB	NTE	S86A	Arabidopsis thaliana	+	[19,20]
		S86D		–
		S3/23-25A		n.d.	[20]
		S3/23-25A/S86A		n.d.
		S3/23-25D		–
		S3/23-25/S86D		–
	NTE/nPAS	Y104E		–	[20,21]
		Y104F		+
		S80/106A		–	[24]
		S80/106D		+
		S106/227A		+	[25]
phyD	NTE	S82A	Arabidopsis thaliana	+	[20]
		S88A		+
		S88D		–
phyE	NTE	S50A	Arabidopsis thaliana	n.d.	[20]
		S50D		–
		S53A		n.d.

NTE, N-terminal extension; Hinge, the linking region between photosensory module (PSM) and output module (OPM); nPAS, N-terminal Per/Arnt/Sim domain.
Phytochrome mutants are named with the substitution of corresponding phosphorylatable amino acid residue(s).
The phytochrome activity of mutants is shown as either hyperactive (+), hypoactive (–), or n.d. (no difference compared with wild-type phytochromes).