Tissue-specific expression of NPC genes in response to dietary sterols in the desert locust

Sterols are essential nutrients for insects, serving as precursors for cell membrane components and molting hormones. Unlike mammals, insects cannot synthesize sterols de novo and must absorb them from dietary sources. The Niemann–Pick type C (NPC) gene family—including NPC1a, NPC1b, and NPC2— facilitates sterol uptake and intracellular transport. While NPC function has been studied in model insects such as Drosophila melanogaster and Bombyx mori, their roles remain unexplored in ecologically important pest species. This study investigates NPC gene expression across tissues of Schistocerca gregaria under contrasting dietary sterol conditions. Based on findings from from model systems, we hypothesize that NPC1b will be midgut-enriched and upregulated under cholesterol-deficient diets, while NPC1a and NPC2 will exhibit broader expression profiles involved in intracellular sterol trafficking. To test this, we are conducting quantitative real-time PCR (RT-qPCR) on the midgut, fat body, and caeca of locusts reared on cholesterol-rich and cholesterol-deficient diets. Transcript levels will be normalized to housekeeping genes and analyzed for both tissue specificity and dietary responsiveness.
This research provides the first systematic analysis of NPC gene expression as a function of dietary sterol. These insights will advance our understanding of insect sterol regulation and could support the development of novel pest management strategies that target nutrient acquisition.