Enhancing plant defensins in a desert shrub: Exploring a regulatory pathway of AnWRKY29.

A distinct family of plant-specific WRKY transcription factors plays a crucial role in modulating responses to biotic and abiotic stresses. In this investigation, we unveiled a signaling pathway activated in the desert shrub Ammopiptanthus nanus during feeding by the moth Spodoptera exigua. The process involves a Ca2+ flux that facilitates interaction between the protein kinase AnCIPK12 and AnWRKY29. AnWRKY29 directly interacts with the promoters of two key genes encoding AnPDF1 and AnHsfB1 , involved in the biosynthesis of plant defensins. Consequently, AnWRKY29 exerts its transcriptional regulatory function, influencing plant defensins biosynthesis. This discovery implies that A. nanus can bolster resistance against herbivorous insects like S. exigua by utilizing this signaling pathway, providing an effective natural defense mechanism that supports its survival and reproductive success. • The study uncovers a signaling pathway in Ammopiptanthus nanus triggered by herbivore feeding. • AnCIPK12 physically interacts with AnWRKY29. • This interaction is facilitated by the Ca2+ flux. • AnWRKY29 plays a dual role in plant defensins biosynthesis, activating AnPDF1 and repressing AnHsfB1. • AnHsfB1 is a transcriptional repressor of AnPDF1. • A complex regulatory network, including AnWRKY29 and AnHsfB1, governs plant defensins biosynthesis in response to herbivore feeding. [ABSTRACT FROM AUTHOR]