The vATPase holoenzyme consists of two functional subcomplexes, the cytoplasmic (peripheral) V
1 and the membrane-embedded V
0. Both V
1 and V
0 sectors contain eight subunits, with stoichiometry of A
3B
3CDE
3FG
3H in V
[...] Read more.
The vATPase holoenzyme consists of two functional subcomplexes, the cytoplasmic (peripheral) V
1 and the membrane-embedded V
0. Both V
1 and V
0 sectors contain eight subunits, with stoichiometry of A
3B
3CDE
3FG
3H in V
1 and ac
8c’c”def(Voa1p) in V
0 respectively. However, the function of G subunit has not been characterized in any non-Drosophilid insect species. In the present paper, we uncovered that
HvvATPaseG was actively transcribed from embryo to adult in a Coleopteran pest
Henosepilachna vigintioctopunctata. Its mRNA levels peaked in larval hindgut and Malpighian tubules. RNA interference (RNAi)-mediated knockdown of
HvvATPaseG significantly reduced larval feeding, affected chitin biosynthesis, destroyed midgut integrity, damaged midgut peritrophic membrane, and retarded larval growth. The function of Malpighian tubules was damaged, the contents of glucose, trehalose, lipid, total soluble amino acids and protein were lowered and the fat bodies were lessened in the
HvvATPaseG RNAi larvae, compared with those in the PBS- and ds
egfp-fed beetles. In contrast, the amount of glycogen was dramatically increased in the
HvvATPaseG depletion ladybirds. As a result, the development was arrested, pupation was inhibited and adult emergence was impaired in the
HvvATPaseG hypomorphs. Our results demonstrated that G subunit plays a critical role during larval development in
H. vigintioctopunctata.
Full article
