Effect of UV-B radiation on kaempferol glycosides in Arabidopsis thaliana

The profiles of kaempferol glycosides,including kaempferol-3-O-rhamnosyl glucoside7-O-rhamnoside(K1),kaempferol-3-O-glucoside-7-O-rhamnoside(K2) and kaempferol-3-O-rhamnoside7-O-rhamnoside(K3),and the expression of related genes in response to UV-B radiation(40 μw·cm-2) for 7 d was analyzed in Arabidopsis thaliana.The results showed that the contents of three kaempferol glycosides in young seedlings were about 10 times of those in mature seedlings.All three kaempferol glycosides contents and the expression of kaempferol glycosides biosynthesis genes chs and fls1 in young seedlings were higher than those in control plants,and the kaempferol glycosides were accumulated in response to UV-B exposure for 7 d.The changes of different kaempferol glycosides profile in response to UV-B treatment were different between young and mature seedlings,which could be dued to different roles in defense mechanisms.