Transcriptomic response of cowpea bruchids to N‐acetylglucosamine‐specific lectins

Abstract

Griffonia simplicifolia lectin II (GSII) and wheat germ agglutinin (WGA) are N-acetylglucosamine-binding lectins. Previous studies demonstrated that they have anti-insect activity, a property potentially useful in pest control. To gain some insight into the insect response to dietary lectins, we performed transcriptomic analysis using the cowpea bruchid (Callosobruchus maculatus) midgut microarray platform we built. Compared to the nonnutritional cellulose treatment, dietary lectins induced more profound changes in gene expression. Ingestion of relatively high doses of lectins for 24 h resulted in alteration of gene expression involved in sugar and lipid metabolism, transport, development, defense, and stress tolerance. Metabolic genes were largely downregulated. Moreover, we observed disorganized microvilli resulting from ingestion of WGA. This morphological change is consistent with the lectin-induced changes in genes related to midgut epithelial cell repair. In addition, suboptimal nutrient conditions may serve as a stress signal to trigger senescence processes, leading to growth arrest and developmental delay.

Plant Defense Inhibitors Affect the Structures of Midgut Cells inDrosophila melanogasterandCallosobruchus maculatus

“…The w 11,18 strain of D. melanogaster was obtained from Misha Ludwig (University of Chicago). The larvae were reared to the third instar on a Formula 24 Drosophila diet (Carolina Biological Supply) at room temperature (22–23°C and 60–70% relative humidity).…”

“…Wheat germ agglutinin (WGA) is a lectin that binds N -acetyl-D-glucosamine, the building block of chitin found in insect cuticle and peritrophic matrix (PM) 6,10. Ingestion of WGA can cause structural damage in the midguts of coleopterans,11 lepidopterans,12–14 and dipterans 6. αAIs block starch digestion by complexing with alpha-amylase,10,15 and delay larval development and maturation of several coleopterans and two lepidopterans 16–19…”

Genomics analysis ofDrosophila sechelliaresponse toMorinda citrifoliafruit diet

“…Many prior studies in other insects have focused on identifying genes important for insect specialization on specific host plants by using a genome-wide transcriptomic approach. This approach has been applied to investigations of insects in response to specific toxins found in their preferred host plant ( Wang et al 2015 ; Lanno et al 2017 , 2019 ; Li et al 2019 ; Drum et al 2022 ) while others investigated gene expression responses to the different host plant as a whole ( Govind et al 2010 ; Bansal et al 2014 ; Hoang et al 2015 ; Crava et al 2016 ; De Panis et al 2016 ; Birnbaum et al 2017 ; Schweizer et al 2017 ). Feeding on different food sources therefore differ in many ways (e.g.…”