Journal Article

Inhibitory effects of plant latex on trehalase activity and trehalase gene expression in the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae)

Tatun, N., University of Phayao (Thailand). School of Science, Tungjitwitayakul, J., University of Phayao (Thailand). School of Science, Sakurai, S., Kanazawa University (Japan). Division of Life Sciences

2014

Overview

Plant latex contains proteins and other components that defend plants against herbivorous insects. We determined the inhibitory activity of methanolic extracts of latex obtained from three species of plant: mulberry, Morus alba; jackfruit, Artocarpus heterophyllus; and weeping fig, Ficus benjamina, against trehalase in the red flour beetle, Tribolium castaneum. We also determined the changes that occurred throughout the life of the insect in the enzymatic activities of soluble and membrane-bound trehalase and the expression profiles of the genes encoding the two types of trehalase. Soluble trehalase activity was higher than membrane-bound trehalase activity in larvae and adults, whereas there was little difference in eggs, prepupae and pupae. The expression of the trehalases, TcTre-1 and TcTre-2, changed during insect development but did not coincide closely with changes in enzymatic activity, indicating that these changes did not necessarily depend on gene expression. All of three plant latices tested inhibited the activities of both the soluble and membrane-bound trehalase. At the gene expression level, these latices reduced the expression of TcTre-1 but not TcTre-2, indicating that the latices contain component(s) that selectively inhibit gene expression or at least differentially inhibit these two trehalase genes. The inhibition of trehalase activity resulted in a 140% increase in the concentration of trehalose in the beetle and a decrease in glucose concentration to 72% of the control. These findings show that the latices tested contain components that inhibit trehalase activity and TcTre-1 expression and thus, may contribute to the plants' defense against herbivorous insects.

• Publisher: Institute of Entomology,Institute of Entomology, Biology Centre, Czech Academy of Science
• Subject: ADULTE / ADULTOS / ADULTS / Artocarpus heterophyllus / BIOASSAYS / CALENTAMIENTO / CHAUFFAGE / Chitinase / COLEOPTERA / DIALISIS / DIALYSE / DIALYSIS / DIGESTION / DNA FINGERPRINTING / EMPREINTE ADN / ENSAYO BIOLOGICO / Enzymatic activity / ENZYME INHIBITORS / Enzymes / EVALUACION DEL IMPACTO / EVALUATION DE L'IMPACT / EXPERIMENTACION IN VIVO / EXPERIMENTATION IN VIVO / EXTRACTOS / EXTRACTS / EXTRAIT / FEUILLE / FICUS BENJAMINA / Gene expression / GLUCOSA / GLUCOSE / HEATING / HOJAS / HUELLAS GENETICAS ADN / IMPACT ASSESSMENT / IN VIVO EXPERIMENTATION / INHIBIDORES DE ENZIMAS / INHIBITEUR D'ENZYME / Insects / LARVAE / LARVAS / LARVE / Latex / LEAVES / MORUS / Morus alba / PCR / plant latex / Plant species / PLANTE / PLANTS / PROTEINAS / PROTEINE / PROTEINS / PUPA / PUPAE / PUPE / Tenebrionidae / TEST BIOLOGIQUE / TREHALASA / TREHALASE / trehalase inhibitor / TREHALOSA / TREHALOSE / TRIBOLIUM CASTANEUM / TRIPSINA / TRYPSIN / TRYPSINE