ABSTRACT
Phytophagous insect incidence is a serious threat for reduction of crop productivity globally. There is anestimation of one fourth of crop is being destroyed by insects annually. Indeed, the development of insectresistant crops is a great milestone in agriculture to increase crop yield and reduce pesticide dependency.Genetic engineering facilitates development of insect resistant crops by expressing bacterial d-endotoxins andvegetative insecticidal proteins and other plant genes like lectins, protease inhibitors, etc. In addition, RNAinterference and genome editing through CRISPR Cas9 also provides new solutions for the development ofinsect-resistant crops. The resultant genetically modified crops showed resistance against lepidopteran, dipteran, homopteran and coleopteran insects. The insect-resistant crops have made a significant economic impactworldwide in terms of higher yield and low pesticide usage. In this review, we focus on different strategies fordeveloping transgenics against insect pest control by expressing different insecticidal proteins in crops
ABSTRACT
Silkworm silk protein fibroin is widely exploited to develop novel silk-based biomaterials due to its stable b-sheetstructure, providing high crystallinity and tensile strength. The polymorphic behaviour of silk fibroin provides awindow to modulate its structural transitions during self-assembly for different functional outcomes. Most studiesare therefore mainly focused on formation of well-developed b-sheet structure and self-assembly of silk fibroinwhich are regulated by many parameters. Glyoxal, a highly reactive a-oxoaldehyde, reacts with different proteinsto form advanced glycation end products (AGEs) following Maillard-like reaction. Considering the significanceof protein modification by glyoxal-derived AGEs, in the present study the effect of glyoxal (250, 500 and1000 lM) on the structure of silk fibroin has been investigated. CD and fluorescence studies reveal that higherconcentrations of the a-oxoaldehyde induce considerable alterations of secondary and tertiary structure of theprotein leading to aggregation following incubation with for 3 weeks. The aggregates exhibit fibrillar morphologywith amyloidal nature as evident from SEM, FTIR and XRD experiments. The findings highlight that glycationinduced modification can be a possible approach for modulating the conformation of the silk protein which may berelevant in connection to clinical, biomedical or synthetic biology based applications.