Rehman Shazia, Aziz Ejaz, Akhtar Wasim, Ilyas Muhammad, Mahmood Tariq
Department of Plant Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan.
Department of Biotechnology, University of Azad Jammu and Kashmir, Muzaffarabad, Pakistan.
Biotechnol Lett. 2017 May;39(5):647-666. doi: 10.1007/s10529-017-2298-1. Epub 2017 Feb 9.
Plant proteinase inhibitor-II (PI-II) proteins are one of the promising defensive proteins that helped the plants to resist against different kinds of unfavorable conditions. Different roles for PI-II have been suggested such as regulation of endogenous proteases, modulation of plant growth and developmental processes and mediating stress responses. The basic knowledge on genetic and molecular diversity of these proteins has provided significant insight into their gene structure and evolutionary relationships in various members of this family. Phylogenetic comparisons of these family genes in different plants suggested that the high rate of retention of gene duplication and inhibitory domain multiplication may have resulted in the expansion and functional diversification of these proteins. Currently, a large number of transgenic plants expressing PI-II genes are being developed for enhancing the defensive capabilities against insects, bacteria and pathogenic fungi. Much emphasis is yet to be given to exploit this ever expanding repertoire of genes for improving abiotic stress resistance in transgenic crops. This review presents an overview about the current knowledge on PI-II family genes, their multifunctional role in plant defense and physiology with their potential applications in biotechnology.
植物蛋白酶抑制剂-II（PI-II）蛋白是一类很有前景的防御蛋白，可帮助植物抵御各种不利条件。人们提出了PI-II的不同作用，如调节内源性蛋白酶、调节植物生长和发育过程以及介导应激反应。关于这些蛋白的遗传和分子多样性的基础知识，为深入了解它们在该家族不同成员中的基因结构和进化关系提供了重要线索。对不同植物中这些家族基因的系统发育比较表明，基因重复和抑制结构域倍增的高保留率可能导致了这些蛋白的扩增和功能多样化。目前，大量表达PI-II基因的转基因植物正在被培育，以增强对昆虫、细菌和致病真菌的防御能力。然而，利用这一不断扩大的基因库来提高转基因作物的非生物胁迫抗性，仍需给予更多关注。本综述概述了目前关于PI-II家族基因的知识、它们在植物防御和生理学中的多功能作用以及在生物技术中的潜在应用。
