ABSTRACT

Plants have evolved elaborate physiological and molecular responses to diverse environmental challenges, including biotic and abiotic stresses. Accumulating evidence suggests that biotic and abiotic stress signaling pathways are intricately intertwined, and factors involved in molecular crosstalk between these pathways have been identified. The R2R3-type MYB96 transcription factor is a key player that mediates plant response to drought and osmotic stresses as well as to microbial pathogens, acting as a molecular signaling integrator. Here, we report that MYB96 is required for the transcriptional regulation of SUGAR TRANSPORT PROTEIN 13 (STP13) that lies at the intersection of abscisic acid (ABA) and defense signaling pathways. MYB96 directly binds to the STP13 promoter and activates gene expression upon exogenous application of ABA and bacterial flagellin peptide flg22. Our findings indicate that MYB96 integrates biotic and abiotic stress signals and possibly induces sugar uptake to confer tolerance to a wide range of adverse environmental challenges.

摘要

植物已经进化出复杂的生理和分子反应，以应对各种环境挑战，包括生物和非生物胁迫。越来越多的证据表明，生物和非生物应激信号通路错综复杂地交织在一起，并且已经确定了参与这些通路之间分子串扰的因素。R2R3 型 MYB96 转录因子是介导植物对干旱和渗透胁迫以及微生物病原体的反应的关键参与者，充当分子信号整合器。在这里，我们报告 MYB96 是糖转运蛋白13 ( STP13 ) 的转录调控所必需的，该蛋白位于脱落酸 (ABA) 和防御信号通路的交汇处。MYB96 直接与 STP13结合外源应用 ABA 和细菌鞭毛蛋白肽 flg22 后启动子并激活基因表达。我们的研究结果表明，MYB96 整合了生物和非生物胁迫信号，并可能诱导糖摄取以赋予对各种不利环境挑战的耐受性。