Knocking Out of UDP–Glycosyltransferase Gene <i>UGT2B10</i> via CRISPR/Cas9 in <i>Helicoverpa armigera</i> Reveals Its Function in Detoxification of Insecticides

The role of insect UDP-glycosyltransferases (UGTs) in the detoxification of insecticides has rarely been reported. A UGT gene <i>UGT2B10</i> was previously found overexpressed in a fenvalerate-resistant strain of <i>Helicoverpa armigera</i>. Herein, <i>UGT2B10</i> was cloned, and its involvement in insecticide detoxification was investigated. <i>UGT2B10</i> was highly expressed in the larvae, mainly in the fat body and midgut. Treatment with UGT inhibitors 5-nitrouracil and sulfinpyrazone significantly enhanced the fenvalerate toxicity. Knocking down <i>UGT2B10</i> by RNAi significantly increased the larvae mortality by 17.89%. <i>UGT2B10</i> was further knocked out by CRISPR/Cas9, and a homozygous strain (HD-d<i>UGT2B10</i>) with a C-base deletion at exon 2 was obtained. The sensitivity of HD-d<i>UGT2B10</i> to fenvalerate, deltamethrin, cyantraniliprole, acetamiprid, and lufenuron increased significantly, with sensitivity index increased 2.523-, 2.544-, 2.250-, 2.473-, and 3.556-fold, respectively. These results suggested that <i>UGT2B10</i> was involved in the detoxification of <i>H. armigera</i> to insecticides mentioned above, shedding light upon further understanding of the detoxification mechanisms of insecticides by insect UGTs.