Plant serpin protease inhibitors: specificity and duality of function

• Published in: Journal of experimental botany Vol. 70; no. 7; pp. 2077 - 2085
• Main Authors: Cohen, Maja, Davydov, Olga, Fluhr, Robert
• Format: Journal Article
• Language: English
• Published: UK Oxford University Press 12.04.2019
• Subjects: plant cell death; Cysteine and serine proteases; serpin
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/ery460

This review focuses on serpins, a conserved family of protease inhibitors, and on their biological role in the regulation of cell death, plant protection, and as chaperone-like entities. Abstract The serpins are a family of structurally conserved protease inhibitors found in all animal and plant kingdoms. After interaction with their cognate substrate(s), their native energetically stressed state is relaxed by hydrolysis, resulting in a semi-stable covalent bond that disables the protease. The inherent flexible serpin structure supports additional non-inhibitory functions. This review will focus on several biological functions attributed to plant serpins, ranging from specific cell death protease inhibitors to a stabilizing role for β-amylase in seeds. Functional conservation of a particular serpin type, the LR serpins, is suggested by its compelling ubiquity throughout the plant kingdom. The multiple target specificity of plant serpins including the LR serpins enables them to perform dual functions that are not mutually exclusive both as a regulator of cell death and as a protective anti-pathogenic protein.