The regulation of lipid metabolism by a hypothetical P-loop NTPase and its impact on fecundity of the brown planthopper.
Insect fecundity can be regulated by multiple genes in several important signaling pathways which form an extremely complicated regulatory network. However, there are still many genes that have significant impact on insect fecundity but their action mode are still unknown.



Quantitative real-time PCR (qRT-PCR), immunofluorescence and western blot were used to study the expression profile of Nl23867 in the brown planthopper, Nilaparvata lugens. RNA interference (RNAi), RNA-seq and isobaric tags for relative and absolute quantification (iTRAQ) were performed to investigate the action mode of Nl23867 in the regulation of fecundity. High performance liquid chromatography (HPLC) analysis was performed to detect the fatty acid contents.



We show that knockdown of Nl23867, a gene encoding a hypothetical P-loop NTPase, significantly decreased fecundity of N. lugens. Underdeveloped ovaries, fewer eggs laid and reduction in vitellogenin (Vg) protein expression were observed after RNAi knockdown of Nl23867, and most of the affected genes and pathways are fatty acid metabolism-related. We further determined that Nl23867 directly impacts the palmitic acid biosynthesis by regulating the expression of palmitoyl-protein thioesterase (PPT), subsequently affecting the content of total lipids in N. lugens.



Nl23867 regulates the fecundity of N. lugens by modulating the biosynthetic pathway of palmitic acid and affecting lipid metabolism during vitellogenesis and oocyte development.



The presented study pioneers the exploration into how a function-unknown gene takes part in the regulation of fecundity in an insect, and will contribute to the construction of gene regulatory network for insect fecundity.
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Rui
R
Pang
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Jieqi
J
Qiu
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Tengchao
T
Li
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Pan
P
Yang
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Lei
L
Yue
ZhiXin High School, Guangzhou, 510080, China.
Yixin
Y
Pan
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China. Electronic address: lsszwq@mail.sysu.edu.cn.
Wenqing
W
Zhang
D000818:Animals; D005298:Fertility; D053263:Gene Regulatory Networks; D006430:Hemiptera / Q000502:physiology*; D050356:Lipid Metabolism; D043583:Nucleoside-Triphosphatase / Q000235:genetics*; D009865:Oocytes / Q000502:physiology; D019308:Palmitic Acid / Q000378:metabolism; D014818:Vitellogenesis
D019308:Palmitic Acid; D043583:Nucleoside-Triphosphatase