The midgut, which plays a major role in the feeding behavior of insects, is believed to be controlled by various factors including neuropeptides. In the present study, we identified a neuropeptide crustacean cardioactive peptide (CCAP) as a novel gut factor in insects. CCAP was isolated from the midgut of the cockroach, Periplaneta americana. RT-PCR analysis detected the expression of the cockr...

Phytophagous insects frequently encounter reactive oxygen species (ROS) from exogenous and endogenous sources. To overcome the effect of ROS, insects have evolved a suite of antioxidant defense genes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione peroxidase (GPX). The emerald ash borer (Agrilus planipennis Fairmaire), an exotic invasive insect pes...

Autophagy requires the conjugation of autophagy-related protein 12 (ATG12) to autophagy-related protein 5 (ATG5) through covalent attachment. However, the signals regulating ATG12-ATG5 conjugation are unclear. The larval midgut of lepidopteran insects performs autophagy and apoptosis sequentially during the transition of larvae to pupae under regulation by the steroid hormone 20-hydroxyecdysone...

We screened for α-glucosidase inhibitors from 12 traditional medicinal plants used for the treatment of diabetes. Potent α-glucosidase inhibitory activity was found in aqueous extract of Psidium guajava leaves and Syzygium cumini Linn seed extract. Active principles inhibiting α-glucosidase were isolated and identified as apigenin 7O-glucoside in the S.cumini Linn seed extract and Dihydro-3,3’,...

The bacterium Bacillus thuringiensis produces ICPs (insecticidal crystal proteins) that are deposited in their spore mother cells. When susceptible lepidopteran larvae ingest these spore mother cells, the ICPs get solubilized in the alkaline gut environment. Of approx. 140 insecticidal proteins described thus far, insecticidal protein Cry1Ac has been applied extensively as the main ingredient o...

Insecticidal crystal proteins of Bacillus thuringiensis bind to receptors in the midgut of susceptible insects leading to pore formation and death of the insect. The identity of the receptor is not clearly established. Recently a direct interaction between a cloned and heterologously expressed aminopeptidase (slapn) from Spodoptera litura and the Cry1C protein was demonstrated by immunofluoresc...

The insect digestive system is the first line of defence protecting cells and tissues of the body from a broad spectrum of toxins and antinutritional factors in its food. To gain insight into the nature and breadth of genes involved in adaptation to dietary challenge, a collection of 20 352 cDNAs was prepared from the midgut tissue of cowpea bruchid larvae (Callosobruchus maculatus) fed on regu...

Glycoside Hydrolases (GHs) are enzymes able to recognize and cleave glycosidic bonds. Insect GHs play decisive roles in digestion, in plant-herbivore, and host-pathogen interactions. GH activity is normally measured by the detection of a release from the substrate of products as sugars units, colored, or fluorescent groups. In most cases, the conditions for product release and detection differ,...

In immunobiochemical blots, polyclonal antibodies against subunits of plant and mammalian vacuolar-type ATPases (V-ATPases) cross-react strongly with corresponding subunits of larval Manduca sexta midgut plasma membrane V-ATPase. Thus, rabbit antiserum against Kalanchoe daigremontiana tonoplast V-ATPase holoenzyme cross-reacts with the 67, 56, 40, 28 and 20 kDa subunits of midgut V-ATPase separ...

In the present study, a 50% ethanolic extract of Orthosiphon stamineus was tested for its α-glucosidase inhibitory activity. In vivo assays of the extract (containing 1.02%, 3.76%, and 3.03% of 3'hydroxy-5,6,7,4'-tetramethoxyflavone, sinensetin, and eupatorin, resp.) showed that it possessed an inhibitory activity against α-glucosidase in normal rats loaded with starch and sucrose. The results ...