Functional analysis of DGAT1 in the cotton bollworm, Helicoverpa armigera

Triglycerides are essential in energy homeostasis and other important physiological processes. Acyl-coenzyme A (CoA): diacylglycerol acyltransferase (DGAT) mediates the terminal and committed reaction in triglyceride (TG) synthesis, and two groups of DGAT enzymes, DGAT1 and DGAT2, play important roles in TG synthesis in mammals. However, molecular mechanism of triglyceride metabolism is poorly understood in insects. In this study, we focused on DGAT1. By exploring the genomic information, we found that most insects including Helicoverpa armigera possessed one DGAT1 gene but aphids did not have DGAT1 homolog. DGAT1 was enriched in the midgut of H. armigera larvae and actively involved in TG synthesis in this tissue. However, DGAT1 seemed to play no role in the fat body, where TG was stored. Moreover, DGAT1 was essential for TG synthesis in the ovaries of H. armigera adults, and reproduction was severely impaired when DGAT1 function was disrupted. Our work provided important information on the function of DGAT1 in H. armigera, and improved our understanding of lipid metabolism in insects.

Automated summary

This study focused on the function of DGAT1 in Helicoverpa armigera and found that DGAT1 played important roles in triglyceride synthesis in the midgut and ovaries, as well as in reproduction. This work provides valuable information for understanding lipid metabolism in insects.