Abstract

Simple SummaryVacuolar ATPase (vATPase), a proton pump driven by ATP hydrolysis, acts as a membrane energizer to motivate the movement of ions and nutrients across the cellular membrane in insect guts and Malpighian tubules, among others. The vATPase holoenzyme contains 16 subunits. Out of these subunits, mammalian G subunit includes three isoforms (G1-G3) which are encoded by three distinctive genes. The physiological role of a specific G isoform can be compensated by others. Thus, current experimental evidence on the in vivo function of G is rather limited among eight V1subunits. In the present paper, particular attention was paid to an insect model,Henosepilachna vigintioctopunctataladybird, a serious defoliator of Solanaceae and Cucurbitaceae plants in many Asian countries. Given that the beetle is sensitive to RNA interference (RNAi),HvvATPaseGgene was knocked down by ingestion of its corresponding dsRNA at the fourth-instar larval stage. Silence ofHvvATPaseGaffected larval growth and survival, impaired pupation and adult emergence. Our results provide a basis for further functional research on the vATPase G subunit in insects and suggest new ideas for the management ofH. vigintioctopunctata.AbstractThe vATPase holoenzyme consists of two functional subcomplexes, the cytoplasmic (peripheral) V1and the membrane-embedded V0. Both V1and V0sectors contain eight subunits, with stoichiometry of A3B3CDE3FG3H in V1and ac8c’c”def(Voa1p) in V0respectively. However, the function of G subunit has not been characterized in any non-Drosophilid insect species. In the present paper, we uncovered thatHvvATPaseGwas actively transcribed from embryo to adult in a Coleopteran pestHenosepilachna vigintioctopunctata. Its mRNA levels peaked in larval hindgut and Malpighian tubules. RNA interference (RNAi)-mediated knockdown ofHvvATPaseGsignificantly reduced larval feeding, affected chiti