School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China; Joint Laboratory Safety of International Cooperation of Agriculture & Agricultural-Products, Yangzhou University, Yangzhou 225009, PR China.
School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
Pestic Biochem Physiol. 2019 Jan;153:176-184. doi: 10.1016/j.pestbp.2018.11.016. Epub 2018 Nov 29.
Hexokinase is a rate-limiting enzyme that plays pivotal roles in glucose homeostasis and energy metabolism via glucose (Glc) phosphorylation and Glc signaling mediation. Previous investigations have revealed the modulatory role of Hexokinase (Hex) genes involved in proper glucose regulation during insect diapause and embryo development, whereas whether it functions in insect fecundity remains largely unknown. We aimed to explore the relationship between Triazophos (TZP)-induced Hex-1 and fecundity of female Nilaparvata lugens. In this study, Hex-1 expression were characterized at different developmental stages and in various tissues of N. lugens, with the highest expression registered in brain tissues and 5th instar nymph. The present findings indicated that TZP + dsHex-1 silencing significantly reduced protein synthesis, including the fat body and ovarian protein content of female adults. Meanwhile, the glycometabolism with respect to the soluble sugar, trehalose and glucose content in female adults were strikingly influenced as a result of Hex-1 knockdown. The relative transcript level of Hex-1, vitellogenin (NlVg) and vitellogenin receptor (NlVgR) considerably decreased in TZP + dsHex-1 treated females compared to TZP and TZP + dsGFP-treated groups. More importantly, TZP + dsHex-1 silencing led to reduced number of eggs laid and vitellogenin (Vg) accumulation as well as retarded ovary development compared with TZP-treated and TZP + dsGFP-treated groups. Taken together, it is proposed that Hex-1 implicates in N. lugens fecundity by exerting profound effects on glycometabolism, protein sythesis and NlVg expression.
己糖激酶是一种限速酶，通过葡萄糖（Glc）磷酸化和 Glc 信号转导调节，在葡萄糖稳态和能量代谢中发挥关键作用。先前的研究表明，己糖激酶（Hex）基因的调节作用参与昆虫滞育和胚胎发育过程中的葡萄糖调节，而其在昆虫生殖力中的作用在很大程度上尚不清楚。我们旨在探讨三唑磷（TZP）诱导的 Hex-1 与褐飞虱雌性生殖力之间的关系。在这项研究中，我们研究了 N. lugens 不同发育阶段和不同组织中 Hex-1 的表达情况，结果表明，Hex-1 在脑组织和 5 龄若虫中表达最高。本研究结果表明，TZP+dsHex-1 沉默显著降低了包括脂肪体和卵巢在内的成年雌性个体的蛋白质合成。同时，由于 Hex-1 敲低，成年雌性个体的糖代谢受到显著影响，表现为可溶性糖、海藻糖和葡萄糖含量的变化。与 TZP 和 TZP+dsGFP 处理组相比，TZP+dsHex-1 处理组的 Hex-1、卵黄蛋白原（NlVg）和卵黄蛋白原受体（NlVgR）的相对转录水平显著降低。更重要的是，与 TZP 处理组和 TZP+dsGFP 处理组相比，TZP+dsHex-1 沉默导致产卵数减少、卵黄蛋白原（Vg）积累减少以及卵巢发育迟缓。综上所述，己糖激酶通过对糖代谢、蛋白质合成和 NlVg 表达产生深远影响，参与褐飞虱的生殖力。
