Nanjing Forestry University, Nanjing 210037, China; Zhejiang Agricultural & Forestry University, Hangzhou 311300, China.
Zhejiang Agricultural & Forestry University, Hangzhou 311300, China.
Gene. 2022 May 20;823:146350. doi: 10.1016/j.gene.2022.146350. Epub 2022 Feb 18.
Bursaphelenchus xylophilus is an invasive plant-parasitic nematode causing the notorious pine wilt disease (PWD) worldwide, which results in huge economic losses. G protein-coupled receptors (GPCRs) play an essential role in mating and reproduction behavior of animals. As a unique biogenic amine in invertebrates, octopamine (OA) can regulate a variety of physiological and behavioral responses by binding specific GPCRs. These specific GPCRs are also called octopamine receptors (OARs), and octr-1 is one of them. However, Bxy-octr-1 is unknown in B. xylophilus. Therefore, we investigated the expression pattern and biological function of Bxy-octr-1. Bioinformatics analysis indicated that Bxy-octr-1 was evolutionarily conserved. The real-time quantitative PCR data revealed that Bxy-octr-1 expression was required throughout the entire life of B. xylophilus. mRNA in situ hybridization showed that Bxy-octr-1 was mainly located in the cephalopharynx, body wall muscle, intestine, and gonadal organs of B. xylophilus. RNA interference (RNAi) showed that embryo hatching rates and locomotion speeds were both dramatically decreased. Obvious abnormal phenotypes were observed in the second-stage of juveniles after RNAi treated. Furthermore, its ontogenesis was stunting. Lack of Bxy-octr-1 reduced fecundity of females, of which 31.25% of them could not successfully ovulate. In addition, the error positioning ratio of the nematode was significantly increased. Our study suggests that Bxy-octr-1 is indispensable for locomotion, early ontogenesis and mating behavior in B. xylophilus.
松材线虫是一种入侵的植物寄生线虫，引起了臭名昭著的松材线虫萎蔫病（PWD），造成了巨大的经济损失。G 蛋白偶联受体（GPCRs）在动物的交配和繁殖行为中起着至关重要的作用。章鱼胺（OA）作为一种独特的无脊椎动物生物胺，可以通过与特定的 GPCR 结合来调节各种生理和行为反应。这些特定的 GPCR 也被称为章鱼胺受体（OARs），其中之一是 octr-1。然而，B. xylophilus 中的 Bxy-octr-1 尚不清楚。因此，我们研究了 Bxy-octr-1 的表达模式和生物学功能。生物信息学分析表明，Bxy-octr-1 在进化上是保守的。实时定量 PCR 数据显示，B. xylophilus 整个生命周期都需要 Bxy-octr-1 的表达。mRNA 原位杂交显示，Bxy-octr-1 主要位于松材线虫的头咽、体壁肌肉、肠和性腺器官中。RNA 干扰（RNAi）表明，胚胎孵化率和运动速度都明显降低。RNAi 处理后，观察到第二阶段幼虫出现明显的异常表型。此外，其个体发生发育迟缓。缺乏 Bxy-octr-1 会降低雌性的繁殖力，其中 31.25%的雌性无法成功产卵。此外，线虫的定位错误率显著增加。我们的研究表明，Bxy-octr-1 对松材线虫的运动、早期个体发生和交配行为是不可或缺的。
