Mechanistic insights into the temperature regulation of plant immunity

植物病害加上与气候变化相关的温度异常对农业和粮食安全构成严重威胁。以前的研究已经对植物如何抵御病原体和害虫产生了重要的见解。这些关键的防御反应之一是产生激素水杨酸（SA），它使寄主植物能够在全球范围内控制数千种必要的基因，以抵抗各种各样的病原体。然而，环境因素（如温度升高）如何影响植物SA通路的分子机制尚不清楚。我的研究旨在解决这一重要的知识鸿沟。我之前的工作表明，升高的温度通过下调CALMODULIN-BINDING PROTEIN 60g （CBP60g）的表达来抑制模式植物拟南芥SA的产生。CBP60g编码一个主转录因子，控制植物中许多免疫调节因子，包括与SA产生有关的基因。由于CBP60g基因是整合温度和免疫途径的中心枢纽，它在分子水平上的调节将为温度如何影响植物SA途径提供线索。此外，温度敏感免疫是否在其他植物物种中保守也尚不清楚。我的长期愿景是创建一个综合模型，定义植物如何在不断变化的环境中抵抗病原体。我的研究计划将整合分子、遗传和生化方法，以实现未来五年的三大目标。首先，我们将通过计算机和体内方法确定CBP60g基因表达的必要转录因子。其次，我们将进行基因筛选，发现CBP60g基因在高温下表达的新调控因子，并使用突变方法验证结果。第三，我们将通过研究具有重要农业意义的番茄作物CBP60g基因的表达和SA的产生，来确定温度对宿主免疫的抑制是否在其他植物物种中保守。总的来说，我的研究计划将通过确定导致高温下SA产生受损的必要基因和机制，更准确地解决自然环境中植物疾病的复杂性。这些知识将有助于我们更好地了解植物对各种压力的抵抗力，并有助于提高加拿大和世界各地作物抗病性的策略。对于拟议的研究，HQP将获得优秀的实验室和实践技能，这对他们选择的职业很重要。

Plant diseases combined with climate change-associated temperature anomalies pose serious threats to agriculture and food security. Previous studies have led to significant insights into how plants defend themselves against pathogens and pests. One of these crucial defence responses is the production of the hormone salicylic acid (SA), which allows host plants to globally control thousands of genes necessary to resist a broad range of pathogens. However, the molecular mechanisms underlying how environmental factors (e.g. elevated temperature) affect the plant SA pathway are not well-understood. My research aims to address this important knowledge gap. My previous work showed that elevated temperature suppresses SA production in the model plant Arabidopsis thaliana by downregulating the expression of CALMODULIN-BINDING PROTEIN 60g (CBP60g). CBP60g encodes a master transcription factor controlling many immune regulators in plants, including genes involved in producing SA. Because the CBP60g gene is a central hub in integrating temperature and immune pathways, how it is regulated at the molecular level will provide clues on how temperature influences the plant SA pathway. Additionally, whether temperature-sensitive immunity is conserved in other plant species is also unclear. My long-term vision is to create an integrative model that defines how plants resist pathogens in the context of a changing environment. My research program will integrate molecular, genetic and biochemical approaches in order to pursue three major aims in the next five years. First, we will identify essential transcription factors of CBP60g gene expression using both in silico and in vivo methods. Second, we will perform a genetic screen to discover new regulators of CBP60g gene expression at high temperature and validate the results using mutational approaches. Third, we will determine if temperature suppression of host immunity is conserved in other plant species, by studying CBP60g gene expression and SA production of the agriculturally important tomato crop. Overall, my research program would more accurately address the complexity of plant diseases in the natural environment, by identifying the essential genes and mechanisms that lead to compromised SA production at high temperature. This knowledge should help us better understand plant resilience to various stresses and contribute to strategies in improving crop disease resistance in Canada and worldwide. For the proposed research, HQP will acquire excellent laboratory and practical skills that are important for their chosen careers.