title: Differential protease activity augments polyphagy in Helicoverpa armigera.
abstract: Helicoverpa armigera (Lepidoptera: Noctuidae) and other polyphagous agricultural pests are extending their plant host range and emerging as serious agents in restraining crop productivity. Dynamic regulation, coupled with a diversity of digestive and detoxifying enzymes, play a crucial role in the adaptation of polyphagous insects. To investigate the functional intricacy of serine proteases in the development and polyphagy of H. armigera, we profiled the expression of eight trypsin-like and four chymotrypsin-like phylogenetically diverse mRNAs from different life stages of H. armigera reared on nutritionally distinct host plants. These analyses revealed diet- and stage-specific protease expression patterns. The trypsins expressed showed structural variations, which might result in differential substrate specificity and interaction with inhibitors. Protease profiles in the presence of inhibitors and their mass spectrometric analyses revealed insight into their differential activity. These findings emphasize the differential expression of serine proteases and their consequences for digestive physiology in promoting polyphagy in H. armigera.
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, India.
authors: Y R
authors: YR
authors: Chikate
authors: V A
authors: VA
authors: Tamhane
authors: R S
authors: RS
authors: Joshi
authors: V S
authors: VS
authors: Gupta
authors: A P
authors: AP
authors: Giri
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid; D002918:Chymotrypsin / Q000235:genetics / Q000378:metabolism*; D004032:Diet; D041981:Gastrointestinal Tract / Q000201:enzymology; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D007814:Larva / Q000201:enzymology / Q000254:growth & development; D013058:Mass Spectrometry; D009036:Moths / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D011679:Pupa / Q000201:enzymology / Q000254:growth & development; D060888:Real-Time Polymerase Chain Reaction; D020539:Sequence Analysis, Protein; D014357:Trypsin / Q000235:genetics / Q000378:metabolism*
chemical_list: D019476:Insect Proteins; D002918:Chymotrypsin; D014357:Trypsin