Abstract
Ralstonia solanacearum causes bacterial wilt in several economically important solanaceous. To elucidate the molecular mechanisms of plant-R. solanacearum interactions, we isolate and analyze R. solanacearum-responsive genes from Nicotiana plants. In this report, we focused on NbSec14P with similarity to sec14p from yeast. Introduction of NbSec14P rescued temperature-sensitive growth mutant of yeast. Expression of NbSec14P was strongly induced Nicotiana benthamiana leaves inoculated with non-adapted R. solanacearum. In NbSec14P-silenced plants, growth of non-adapted R. solanacearum was accelerated. Bacterial growth and wilt symptoms by adapted R. solanacearum were also accelerated in the silenced plants. In the silenced plants, expression of EREBP and PR-4 genes was compromised. Activities of phospholipids metabolism-relate enzymes such as phospholipase C and D were also reduced in NbSec14P silenced plants. These results indicate that phospholipid metabolisms might have a role in regulation of the defenses in Nicotiana plants.
