Transcript and protein profiling identify candidate gene sets of potential adaptive significance in New Zealand Pachycladon

Table 4 Glucosinolate metabolism loci up-regulated in transcript and protein profiling

Differentially expressed transcripts				Differentially expressed proteins
CH up	CH down	CH up	CH up	CH up	CH down	CH up	CH up
EX+NZ down	EX+NZ up	EX down	NZ down	EX+NZ down	EX+NZ up	EX down	NZ down
At4g03050	At1g54000	At4g03050	At4g03050		At5g14200	At2g43100
At4g03060		At4g03060	At4g03060
			At5g23010
			At2g43100
EX up	EX down	EX up	EX up	EX up	EX down	EX up	EX up
CH+NZ down	CH+NZ up	CH down	NZ down	CH+NZ down	CH+NZ up	CH down	NZ down
At3g14210	At4g03060	At1g54000	At5g23010	At1g54010	At2g43100
			At3g14210		At3g14220
			At1g54030		At1g54040
NZ up	NZ down	NZ up	NZ up	NZ up	NZ down	NZ up	NZ up
CH+EX down	CH+EX up	CH down	EX down	CH+EX down	CH+EX up	CH down	EX down
At1g54000	At5g23010	At1g54000		At2g43100		At2g43100	At2g43100
	At2g43100			At5g14200		At5g14200	At5g14200
	At4g03050			At1g31180		At1g31180	At1g54040
	At1g54030			At1g54040		*At1g54040*	At1g54030
	At3g14210			At1g54030		At1g54030	At3g14220
				At3g14220		At3g14220

Loci involved in glucosinolate biosynthesis and hydrolysis (italicised) found up-regulated in each of the twelve comparisons by either transcript or protein profiling. Glucosinolate biosynthesis: At4g03050 (oxoglutarate dependent dioxygenase 3, AOP3) and At4g03060 (oxoglutarate dependent dioxygenase 2, AOP2) catalyze the accumulation of hydroxyalkyl and alkenyl glucosinolates, respectively. At5g23010 (methylthioalkylmalate synthase), At2g43100 (methylthioalkylmalate isomerase), At5g14200 (methylthioalkylmalate dehydrogenase), and At1g31180 (methylthioalkylmalate dehydrogenase) are involved in the chain elongation of methionine and thus can be considered indicators for the accumulation of C4 glucosinolates as opposed to C3 glucosinolates. Glucosinolate hydrolysis: At3g14210 (epithiospecifier modifier 1, ESM1) and At1g54040 (epithiospecifier proteins, ESP) determine the outcome of glucosinolate hydrolysis in that ESP is necessary for nitrile formation whereas ESM1 promotes the formation of isothiocyanates. Other myrosinase-binding/associated proteins (At1g54000, At1g54010, At1g54030, At3g14220) whose biological function remains to be determined are also found up-regulated in some of the species. Loci whose expression is in agreement with profiles of glucosinolates (figure 2, additional file 2, figure S1) and glucosinolate hydrolysis products (table 5) are highlighted in bold.

ISSN: 2730-7182