《植物生理学报》 2018, 54(9): 1391-1400

植物Kunitz型蛋白酶抑制剂的结构与功能

张娴, 廖东颖, 缑绪卓, 周嘉裕^*, 廖海^*

西南交通大学生命科学与工程学院, 成都610031

通信作者：周嘉裕；E-mail: ddliaohai@home.swjtu.edu.cn, spinezhou@home.swjtu.edu.cn

摘　要：

Kunitz型蛋白酶抑制剂(KPI)是植物在长期进化过程中所形成的一类抗性多肽, 参与调控胞外及胞内靶蛋白酶的活性, 调控植物细胞生长、细胞周期、细胞凋亡、蛋白质的降解与运输、胁迫应答与生长发育等生理过程。KPI家族成员中常含有1、2个Kunitz结构域, 具有典型的β-三叶草型结构。KPI能够抑制丝氨酸蛋白酶、巯基蛋白酶与天冬氨酸蛋白酶, 其对靶蛋白酶的抑制特异性与强弱主要依赖其抑制中心的若干氨基酸残基。目前, 已从绝大多数被子植物中发现并筛选出KPI, 它受到很多胁迫的诱导。本文结合我们实验室开展的植物KPI的结构与抗虫分子机制的研究, 对有关植物KPI的结构和功能研究进展进行综述。

关键词：Kunitz型蛋白酶抑制剂; 分子结构; 生理功能

收稿：2018-05-31   修定：2018-06-29

资助：国家自然科学基金(31500276)、四川省科技计划(2017-JY0222和2018SZ0061)、成都市科学技术研发项目(2015-HM01-00051-SF和2016-HM01-00260-SF)、国家级大学生创新创业训练计划(201810613080)和个性化实验(GX-201812088)。

Structure and function of plant Kunitz-type protease inhibitors

ZHANG Xian, LIAO Dong-Ying, GOU Xu-Zhuo, ZHOU Jia-Yu^*, LIAO Hai^*

School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China

Corresponding author: ZHOU Jia-Yu; E-mail: ddliaohai@home.swjtu.edu.cn, spinezhou@home.swjtu.edu.cn

Abstract:

Kunitz-type protease inhibitors (KPIs) in plants are a class of resistant peptides formed during longterm evolution. They mainly regulate the activities of extracellular and intracellular target proteases which are involved in plant cell growth, cell cycle, cell apoptosis, protein degradation and transport, stress response, and growth and development. The members of this family usually contain 1–2 Kunitz domains and formed typical β-trefoil fold structure. KPIs are able to inhibit different enzymes, such as serine proteases, cysteine proteases and aspartic proteases, and those inhibitory specificity and strength mainly depend on the residues in the inhibitory center. To date, KPIs have been found in most angiosperm plants, and the expression level of KPI is induced by various stresses. In this paper, the research progresses in the structure and function of plant KPIs are reviewed, and the researches accomplished in our laboratory are also introduced.

Key words: Kunitz-type protease inhibitor; molecular structure; physiological function