Role Of A Lys63-Specific E2 Ubiquitin-Conjugating Enzyme/Variant In Plant Innate Immunity

泛素化是真核生物蛋白质修饰的一个重要过程，它将高度保守的小分子蛋白泛素连接到底物上。泛素化过程涉及三个连续的酶促反应，分别由泛素活化酶（E1）、泛素缀合酶（E2）和泛素连接酶（E3）催化。近年来，泛素化已成为植物对许多病原体免疫的关键调节机制。几种植物E3连接酶已被证明是宿主免疫和免疫相关细胞死亡的正或负调节剂。相反，E2酶在植物免疫中的作用，特别是那些指导非经典赖氨酸63特异性泛素化的酶，几乎是未知的。研究人员对植物免疫开辟了一个新的视角，他们发现番茄对细菌病原体的防御涉及一种指导赖氨酸63特异性泛素化的E2泛素缀合酶。在这个项目中，研究人员将表征赖氨酸63连接的泛素化在植物免疫中的关键组成部分，这对于理解泛素化系统对植物免疫的调节具有根本的重要性。 此外，这项工作将有助于努力解开生物过程和蛋白质的赖氨酸63连接的泛素化，这是目前非常有限的知识控制。该项目的一个组成部分是培训在科学领域代表性不足的少数群体的博士后、研究生和本科生;将该项目的研究结果纳入在PI机构教授的本科生/研究生双列实验室课程，在该机构，少数群体学生目前占学生总数的30%以上;并与阿肯色州合作推广服务的调查人员合作，将该项目的调查结果分发给公众和利益相关者。

Ubiquitination is a major eukaryotic protein modification process that attaches ubiquitin, a highly conserved small protein, to substrates. The ubiquitination process involves three consecutive enzymatic reactions that are catalyzed by ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2) and ubiquitin ligase (E3), respectively. In recent years, ubiquitination has emerged as a key regulatory mechanism of plant immunity against many pathogens. Several plant E3 ligases have been shown to act as either positive or negative regulators of host immunity and immunity-associated cell death. In contrast, roles of E2 enzymes in plant immunity, particularly those that direct non-classical lysine 63-specific ubiquitination, are virtually unknown. Opening a new perspective on plant immunity, the investigators have implicated in tomato defense against a bacterial pathogen an E2 ubiquitin-conjugating enzyme that directs lysine 63-specific ubiquitination. In this project the investigators will characterize key components of lysine 63-linked ubiquitination in plant immunity, which is of fundamental importance to the understanding of the regulation of plant immunity by the ubiquitination system. Additionally, this work will assist in efforts to unravel biological processes and proteins that are controlled by lysine 63-linked ubiquitination, knowledge of which is very limited at present. Integral to this project is training of post-doctoral, graduate and undergraduate students from minority groups that are underrepresented in science; incorporation of findings from this project to a dual-listed undergraduate-/graduate-level laboratory course taught at the PI's institution, where minority students currently make up over 30% of the student population; and partnering of the investigators with the Arkansas Cooperative Extension Service to distribute findings from this project to the general public and stakeholders.