Molecular characterization and functional analysis of daf-8 in pinewood nematode Bursaphelenchus xylophilus
Molecular characterization and functional analysis of daf-8 in pinewood nematode Bursaphelenchus xylophilus
复制标题
松材线虫松材线虫daf-8的分子表征及功能分析
DOI：
--
复制
发表时间：
--
期刊：
影响因子：
--
通讯作者：
Jiafu Hu
中科院分区：
文献类型：
--
作者：
Jinghan Wang;Huan Hong;Rong Xie;Jingjing Ji;Kai Guo;Liqun Bai;Jia Tang;Hongshi Yu;Jianren Ye;Jiafu Hu
松材线虫是引起松树枯萎病的病原体，在世界范围内造成广泛的危害。任何抑制线虫种群增长或阻断其传播的策略都将有助于松材线虫病的防治。daf-8在秀丽隐杆线虫幼虫发育和dauer形成中起着重要作用。然而，很少有人知道它的直向同源物在B。木生植物因此，我们研究了B中daf-8的分子特征和生物学功能。xylophilus（Bx-daf-8）。RT-qPCR结果显示，Bx-daf-8基因在胚胎期表达量逐渐增加，在第2期幼鱼（J2）达到最高水平，随后在J3期急剧下降，并在以后的生活中一直维持低水平表达。采用转基因秀丽隐杆线虫来模拟Bx-daf-8的时空表达模式。Bx-daf-8在胚胎发生早期靠近咽部，在胚胎发生晚期弱分布于全身。在整个胚后发育阶段，头部神经元和尾神经节都有这种现象。重度异常B。Bx-daf-8基因敲除后，可观察到松材线虫胚胎，且孵化率急剧下降。IIS途径的下游基因daf-16-1和da-f16-2在Bx-daf-8敲低后也急剧下降。我们认为TGF β 1与IIS通路在Bx-daf-16的上游相互作用，而daf-8可能是B中daf-16的主要调节因子。木生植物然而，敲低Bx-daf-8并没有导致在dauer幼虫阶段的组成性发育停滞，表明dauer进入过程在B中。xylophilus可能受多个基因控制，比C.优美的Bx-daf-8不能单独控制B中的dauer条目。但它对木虱的胚胎发生是不可缺少的，这为抑制B的种群增长提供了潜在的靶点。木生植物
The pinewood nematode Bursaphelenchus xylophilus, is the causal agent of the pine wilt disease, causing extensive damage worldwide. Any strategies to inhibit the population growth or block the spread of the invasive namatode would greatly contribute to the control of pine wilt disease. daf-8 plays crucial roles in larvae development and dauer formation in Caenorhabditis elegans. However, little is known about its orthologue in B. xylophilus. We therefore investigated the molecular characterization and biological functions of daf-8 in B. xylophilus (Bx-daf-8). RT-qPCR showed the expression level of Bx-daf-8 gradually increased during the embryonic stage, and reached highest level at the second-stage juvenile (J2), and then dramatically dropped at J3, maintaining the low expression level through the rest of its life. Transgenic Caenorhabditis elegans was employed to mimic the spatio-temporal expression pattern of Bx-daf-8. Bx-daf-8 was found close to the pharynx during early embryogenesis and weakly distributed throughout the whole body during late embryogenesis. It was observed in head neurons and tail ganglions through the whole postembryonic stages. Severe abnormal B. xylophilus embryos were observed and the hatching rate was decreased sharply after Bx-daf-8 knockdown. daf-16-1 and da-f16-2, the downstream genes of the IIS pathway, also dropped sharply after Bx-daf-8 knockdown. We proposed that TGF crosstalk with IIS pathway at the upstream of Bx-daf-16, and daf-8 may act as a master regulator of daf-16 in B. xylophilus. However, knockdown of Bx-daf-8 did not lead to constitutive developmental arrest at the dauer larvae stage, indicating the dauer entry process in B. xylophilus might be controled by several genes and is more complicated than that in C. elegans. Bx-daf-8 could not control the dauer entry alone in B. xylophilus, but it was indispensable for the embryogenesis, which provided a potential target for suppressing the population growth of B. xylophilus.