The Rice Transcription Factor WRKY53 Suppresses Herbivore-Induced Defenses by Acting as a Negative Feedback Modulator of Mitogen-Activated Protein Kinase Activity. Issue 4 (9th October 2015)

• Record Type: Journal Article
• Authors: Hu, Lingfei; Ye, Meng; Li, Ran; Zhang, Tongfang; Zhou, Guoxin; Wang, Qi; Lu, Jing; Lou, Yonggen
• Is Part Of: Plant physiology. Volume 169:Issue 4(2015)
• Page Start: 2907
• Page End: 2921
• Publication Date: 2015-10-09
• Subjects: Plant physiology -- Periodicals; Botany -- Periodicals; Periodicals; Electronic journals; 571.2
• DOI: 10.1104/pp.15.01090
• Languages: English
• ISSNs: 0032-0889

Abstract

Abstract : A transcription factor functions as a negative feedback modulator of two mitogen-activated protein kinases and thereby acts as an early suppressor of herbivore-induced defenses in rice. Abstract: The mechanisms by which herbivore-attacked plants activate their defenses are well studied. By contrast, little is known about the regulatory mechanisms that allow them to control their defensive investment and avoid a defensive overshoot. We characterized a rice ( Oryza sativa ) WRKY gene, OsWRKY53, whose expression is rapidly induced upon wounding and induced in a delayed fashion upon attack by the striped stem borer (SSB) Chilo suppressalis . The transcript levels of OsWRKY53 are independent of endogenous jasmonic acid but positively regulated by the mitogen-activated protein kinases OsMPK3/OsMPK6. OsWRKY53 physically interacts with OsMPK3/OsMPK6 and suppresses their activity in vitro. By consequence, it modulates the expression of defensive, MPK-regulated WRKYs and thereby reduces jasmonic acid, jasmonoyl-isoleucine, and ethylene induction. This phytohormonal reconfiguration is associated with a reduction in trypsin protease inhibitor activity and improved SSB performance. OsWRKY53 is also shown to be a negative regulator of plant growth. Taken together, these results show that OsWRKY53 functions as a negative feedback modulator of MPK3/MPK6 and thereby acts as an early suppressor of induced defenses. OsWRKY53 therefore enables rice plants to control the magnitude of their defensive investment during early signaling.