The Effect of Transcription Factor on Defense Mechanisms in -Pingyi.

In the current study, we identified a transcription factor, , from Chinese wild grape, -Pingyi (-PY), which could enhance the main stilbene contents and expression of stilbene biosynthesis genes (/) by overexpression of . The promoter of () was shown to be induced as part of both basal immunity (also called pathogen-associated molecular pattern (PAMP)-triggered immunity, PTI) and effector-triggered immunity (ETI), triggered by the elicitors flg22 and harpin, respectively. This was demonstrated by expression of pVqMYB14 in and . We identified sequence differences, notably an 11 bp segment in that is important for the PTI/ETI, and particularly for the harpin-induced ETI response. In addition, we showed that activation of the promoter correlates with differences in the expression of and stilbene pattern induced by flg22 and harpin. An experimental model of upstream signaling in -PY is presented, where early defense responses triggered by flg22 and harpin partially overlap, but where the timing and levels differ. This translates into a qualitative difference with respect to patterns of stilbene accumulation.