Effect Of Exogenous Methyl Jasmonate-lanolin On Glucosinolates Accoumulation In Arabidopsis Thaliana

Glucosinolates are a group of nitrogen- and sulfur-containing plant natural products found mainly in the the Brassicaceae family. The predominant biological activities of glucosinolates are associated with their breakdown into various products by the action of the myrosinase after wounded. Glucosinolates and their degradation products play special roles in plant defense, human nutrition and cancer prevention. So for a long time, researchers paid much attention to it. To study the effect of MeJA on glucosinolates accumulation, application of methyl jasmonate (MeJA) in lanolin to Arabidopsis thaliana rosette leaves was used and glucosinolates pattern was analized in this study. The main results are as follows.(1) Application of lanolin alone to Arabidopsis thaliana rosette leaves affected the accumulation of glucosinolates. The content of total aliphatic glucosinolate peaked at 36h after lanolin treatment and at 48h the content decreased to the level of Oh. The contents of some short-chain aliphatic glucosinolates (C3-C6 side chains), such as 3-MSO, 4MSOB and 5-MSOP, peaked at 36h after lanolin treatment, and the content of 6-MSOH at 12h and 48h was significantly lower than the Oh content. This indicated that the biosynthesis of 3-MSOP, 4MSOB and 5-MSOP was induced by lanolin, and the biosynthesis of 6-MSOH was significantly repressed by lanolin. The content of long-chain glucosinolates 8-MSOO in treated leaves was always significantly higher than in the untreated leaves, and 8-MTO was significantly lower than untreated leaves within 36h after treatment, suggesting that the synthesis of 8-MSOO were induced by lanolin, whereas 8-MTO was repressed within 36h. The content of total indole glucosinolates was continuously increased after treatment and peaked at 48h. Among the indole glucosinolates, the content of 1MT-I3M was significantly lower than the level of Oh at 24h, and I3M continued to rise and peaked at 48h, and the contents of 4OH-I3M and 4MT-I3M peaked at 36h, this indicated that the accumulation of each individual indole gluconsinolate was induced by lanolin.(2) Application of MeJA (in lanolin) affected the accumulation of glucosinolates in Arabidopsis thaliana rosette leaves. MeJA (in lanolin) promoted the contents of total aliphatic glucosinolate and indole glucosinolate in MeJA treated leaves, and they both peaked at 24h. After MeJA (in lanolin) treatment, the content of all short-chain aliphatic glucosinolates peaked at 24h except that the content of 4-MSOB peaked at 36h, and the contents of long-chain 8-MSOO and 8-MTO both peaked at 36h. Similarly, the contents of I3M,4OH-I3M and 4MT-I3M also peaked at 24h, whereas 1MT-I3M peaked at 12h. This indicated that MeJA and Lanolin could promote the synthesis of glucosinolates.(3) MeJA affected the synthesis of most of the glucosinolates. Compared to +Lanolin- treated leaves, the accumulation of aliphatic glucosinolates and indole glucosinolates in MeJA (in lanolin)-treated leaves was ahead of time, and they both peaked at 24h and significantly higher than the content of those in the +Lanolin-treated leaves, suggesting that MeJA stimulates the accumulation of aliphatic glucosinolates and indole glucosinolates and total glucosinolates. Analysising the induction of aliphatic glucosinolates, we found three short-chain aliphatic glucosinolates (3-MSOP,5-MSOP and 6-MSOH) and two long-chain aliphatic glucosinolates (8-MSOO and 8-MTO) were induced by MeJA, whereas 4-MSOB was not induced. Four indole glucosinolates were all induced by MeJA, and I3M,4OH-I3M and 4MT-I3M were strongly induced at 24h, while 1MT-I3M was induced at 12h.