State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
ZhiXin High School, Guangzhou, 510080, China.
Biochim Biophys Acta Gen Subj. 2017 Jul;1861(7):1750-1758. doi: 10.1016/j.bbagen.2017.03.011. Epub 2017 Mar 16.
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.
昆虫的繁殖力可以通过多个基因在几个重要的信号通路中进行调节，这些通路形成了一个极其复杂的调控网络。然而，仍然有许多对昆虫繁殖力有重大影响但作用模式仍不清楚的基因。
采用定量实时 PCR(qRT-PCR)、免疫荧光和 Western blot 技术研究褐飞虱Nilaparvata lugens 中 Nl23867 的表达谱。采用 RNA 干扰(RNAi)、RNA 测序和相对和绝对定量同位素标记(RT-qPCR)技术研究 Nl23867 在调节繁殖力中的作用模式。采用高效液相色谱(HPLC)分析检测脂肪酸含量。
我们发现，一种编码假定 P 环 NTP 酶的基因 Nl23867 的敲低显著降低了褐飞虱的繁殖力。RNAi 敲低 Nl23867 后，卵巢发育不良，产卵量减少，卵黄蛋白原(Vg)蛋白表达减少，大多数受影响的基因和途径与脂肪酸代谢有关。我们进一步确定，Nl23867 通过调节棕榈酰蛋白硫酯酶(PPT)的表达直接影响棕榈酸的生物合成，从而影响褐飞虱总脂含量。
Nl23867 通过调节棕榈酸的生物合成途径，影响卵黄发生和卵母细胞发育过程中的脂质代谢，调节褐飞虱的繁殖力。
本研究率先探索了一个功能未知的基因如何参与昆虫繁殖力的调节，并将有助于构建昆虫繁殖力的基因调控网络。
