Oxidative Protein-Folding Systems in Plant Cells

Table 1

Components of the system for disulfide bond formation in higher plants.

Species	Name	Domain	Active sites	Location
Disulfide-generating enzymes
Rice	ERO1		Cx4C, CxxC	ER^m
Arabidopsis	ERV1	Erv1/ALR	CxxC, Cx4C	M
Arabidopsis	LTO1	VKOR, TRX	Cx6C, CxxC, CxxC	T^m
Arabidopsis	QSOX1	TRX, Erv1/ALR	CxxC, CxxC, CxxC	W
Thiol-disulfide oxidoreductases
PDI family proteins
Rice	OsPDIL1;1	a-b-b′-a′	CGHC, CGHC	ER^L
Rice	OsPDIL2;3	a-a′-b	CGHC, CGHC	PB^ER
Arabidopsis	AtPDIL1;1	a-b-b′-a′	CGHC, CGHC	ER, G, LV, PSV
Arabidopsis	AtPDIL1;3	c-a-b-b′-a′	CGAC, CGHC	C, ER
Arabidopsis	AtPDIL1;4	c-a-b-b′-a′	CGHC, CGHC	ER, G, N, V, W
Arabidopsis	AtPDIL2;1	a-a′-D	CGHC, CGHC	ER^L
Soybean	GmPDIL-1	a-b-b′-a′	CGHC, CGHC	ER^L
Soybean	GmPDIL-2	c-a-b-b′-a′	CGHC, CGHC	ER^L
Soybean	GmPDIS-1	a-a′-D	CGHC, CGHC	ER^L
Soybean	GmPDIS-2	a-a′-D	CGHC, CGHC	ER^L
Soybean	GmPDIM	a-a′-b	CGHC, CGHC	ER^L
Zn finger proteins
Arabidopsis	LQY1	DnaJ Zn finger	(CxxCxGxG)4	T^m
Arabidopsis	CYO1	DnaJ Zn finger	(CxxCxGxG)2	T^m
Disulfide carrier protein
Arabidopsis	MIA40		CPC	M

Disulfide-generating enzymes and disulfide carrier proteins from rice (Oryza sativa), Arabidopsis (Arabidopsis thaliana), and soybean (Glycine max) characterized to date. C, chloroplasts; ER, endoplasmic reticulum; ER^L, ER lumen; ER^m, ER membranes; G, Golgi; LV, lytic vacuole; N, nucleus; M, mitochondria; PB^ER, ER-derived protein body; PSV, protein storage vacuole; T^m, thylakoid membranes; V, vacuole; W, cell wall.