Table 3. The conserved histidine boxes of the membrane-bound FAD proteins in cucumber.

Type	Protein	His-box 1		His-box 2		His-box 3
		Sequence	Position	Sequence	Position	Sequence	Position
ω-6/Δ-12	CsFAD2.1	HECGH	116–120	HRRHH	152–156	HVIHH	327–331
	CsFAD2.2	HECGH	105–109	HRRHH	141–145	HVAHH	315–319
	CsFAD6	HDCAH	167–171	HDQHH	203–207	HIPHH	363–367
ω-3/Δ-5	CsFAD3	HDCGH	101–105	HRTHH	137–141	HVIHH	304–308
	CsFAD7	HDCGH	170–174	HRTHH	206–210	HVVHH	373–377
Δ-3	CsFAD4	QGHH	160–163	HAWAH	217–221	HSTHH	246–250
Δ-7	CsFAD5.1	HRNLSH	156–161	HRYHH	193–197	HNNHH	325–329
	CsFAD5.2	HRNLSH	68–73	HRCHH	105–109	HNNHH	237–241
	CsFAD5.3	HRNLSH	66–71	HRCHH	103–107	HNNHH	235–239
	CsFAD5.4	HRNLSH	63–68	HRYHH	100–104	HNNHH	232–236
	CsFAD5.5	HRNLAH	63–68	HRCHH	100–104	HNNHH	232–236
	CsFAD5.6	HRNLAH	64–69	HRCHH	101–105	HNNHH	234–238
	CsFAD5.7	HRNLSH	73–78	HRCHH	110–114	HNNHH	243–247
	CsFAD5.8	HRNLSH	64–69	HRYHH	101–105	HNNHH	234–238
	CsFAD5.9	HRNLAH	71–76	HRCHH	108–112	HNNHH	240–244
	CsFAD5.10	HRNLAH	63–68	HRYHH	100–104	HNNHH	232–236
	CsFAD5.11	HRHLTH	71–76	HRYHH	108–112	HNNHH	240–244
	CsFAD5.12	HRQLSH	72–77	HRIHH	109–113	HNNHH	242–246
	CsFAD5.13	HRNLAH	63–68	HRCHH	100–104	HNNHH	232–236
	CsFAD5.14	HRNLAH	62–67	HRCHH	99–103	HNNHH	231–235