"A "Whirly" plant transcription factor is a component of the SA-signaling pathway and is required for maximal disease resistance.”

Developmental Cell 6, 229-240.

Desveaux, D, G Subramanian, C Després, J-N Mess, C Lévesque, PR Fobert, JL Dangl, and N Brisson

Summary "Transcriptional reprogramming is critical for plant dis- ease resistance responses; its global control is not well understood. Salicylic acid (SA) can induce plant defense gene expression and a long-lasting disease resistance state called systemic acquired resistance (SAR). Plant-specific "Whirly" DNA binding proteins were previously implicated in defense gene regulation. We demonstrate that the potato StWhy1 protein is transcriptional activator of genes containing the PBF2 binding PB promoter element. DNA binding activity of AtWhy1, the Arabidopsis StWhy1 ortholog, is induced by SA and is required for both SA-dependent disease resistance and SA-induced expression of an SAR re- sponse gene. AtWhy1 is required for both full basal and specific disease resistance responses. The tranchromatin scription factor-associated protein NPR1 is also rebinding quired for SAR. Surprisingly, AtWhy1 activation by SA is NPR1 independent, suggesting that AtWhy1 works in conjunction with NPR1 to transduce the SA signal. Our analysis of AtWhy1 adds a critical component to the SA-dependent plant disease resistance response."