Changes in Gene Expression in the Larval Gut of Ostrinia nubilalis in Response to Bacillus thuringiensis Cry1Ab Protoxin Ingestion

This microarray was used to monitor gene expression in early third-instar larvae of Bt-susceptible O. nubilalis after 6-h feeding on diet with or without Bacillus thuringiensis (Bt) Cry1Ab protoxin.We identified 174 transcripts, for which the expression was changed more than 2-fold in the gut of the larvae fed Cry1Ab protoxin (p<0.05), representing 80 down-regulated and 94 up-regulated transcripts. Among 174 differentially expressed transcripts, 13 transcripts putatively encode proteins that are potentially involved in Bt toxicity, and these transcripts include eight serine proteases, three aminopeptidases, one alkaline phosphatase, and one cadherin. Cry1Ab protoxin ingestion induced gene expression was measured in O. nubilalis gut at 6 after Cry1Ab protoxin toxin exposure to doses of 0.25 μg/ml artificial diet. three independent experiments were performed using three insect gut samples,and each sample was from five insects' gut pooled.