Peptides of the Innate Immune System of Plants. Part II. Biosynthesis, Biological Functions, and Possible Practical Applications

Abstract

One of the means for regulating the plant innate immune system is activating the synthesis of various defense peptides having diverse structural organization. Some of them possess antimicrobial activity. In plants, defense peptides have various localization; they are often synthesized as multidomain precursor proteins or produced by limited proteolysis, as well as through other degradation pathways. In addition to antimicrobial activity, some of these peptides also display an insecticidal effect, inhibit endo- and exogenous proteases, as well as α-amylases, participate in the transfer of building and signaling hydrophobic molecules, and affect the functioning of ion channels. As a result, peptides of plant innate immune systems not only protect plants against viruses, bacteria, fungi, and insects, but also reinforce their resistance to various types of abiotic stresses and participate in the regulation of plant growth and development. In addition, plant defense peptides can suppress the growth of some human pathogens, possess antitumor activity, exhibit properties of food, inhalation, and latex allergens, and can be used in various areas of medicine. This review summarizes data on biosynthesis, biological functions, and possible practical application of the peptides of the plant innate immune system.