Interaction of insect digestive enzymes with plant protein inhibitors and host-parasite coevolution

Summary A complex of new approaches was used to study the insect-plant coevolution by using cereal pest digestive -amylases and proteinases and their proteinaceous inhibitors in cereals. During evolution, plants can weaken the destructive affects of insect hydrolases at the expense of inhibitors in various ways, including (1) increasing the inhibitor activity and heterogeneity, (2) increasing the complexity of an inhibitor set and (3) producing highly specific insect enzyme inhibitors and bifunctional amylase/proteinase inhibitors. Insects, in turn, can decrease the influence of inhibitors by (1) increasing digestive enzyme activities, (2) by modifying a set of related activities of various digestive hydrolases, (3) by decreasing enzyme sensitivity to inhibitors and (4) by destroying inhibitors in guts by proteinases.Abbreviations IEF isoelectric focusing - TI trypsin inhibitor - CI and C/SI chymotrypsin and chymotrypsin/subtilisin inhibitors - InsAI12 insect amylase inhibitor with molecular weight value of about 12 kDa