Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation.
Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation.
复制标题
HC-DAF-2编码理发杆蠕虫，Haemonchus contortus中的胰岛素样受体激酶，并恢复部分Dauer调节。
DOI：
10.1016/j.ijpara.2014.03.005
复制
发表时间：
2014-06
影响因子：
4
通讯作者：
Hu M
中科院分区：
文献类型：
--
作者：
Li F;Lok JB;Gasser RB;Korhonen PK;Sandeman MR;Shi D;Zhou R;Li X;Zhou Y;Zhao J;Hu M
寄生线虫的感染性L3（iL 3）与自由生活的线虫秀丽隐杆线虫的发育停滞（dauer）幼虫具有共同的行为、形态和发育特征。提出了类似的分子机制调节进入或退出的dauer阶段在C。线虫，以及寄生线虫从自由生活到寄生形式的过渡。在线虫中，调节dauer转换的关键因子之一是由基因Ce-daf-2编码的胰岛素样受体（命名为Ce-daf-2）。然而，在大多数寄生线虫中，对α-2同源物一无所知。在这里，使用PCR为基础的方法，我们确定和特点的基因（HC-daf-2）和其推断的产品（HC-daf-2）在捻转血矛线虫（一个社会经济上重要的反刍动物寄生线虫）。Hc-STAT-2的序列与脊椎动物和无脊椎动物中的胰岛素受体（IR）显示出显著的序列同源性，并且包含保守的结构域。在预测的HC-β 2肽序列中鉴定的编码重要蛋白水解基序（RKRR）的序列与人IR的序列一致，表明其参与IR复合物的形成。Hc-daf-2基因在H.与其他阶段相比，iL 3的表达显著上调。为了比较Hc-daf-2和Ce-daf-2之间的表达模式，将Ce-daf-2或Hc-daf-2启动子与编码GFP的序列融合的报道构建体显微注射到C. elegans和转基因株系的建立和检测。这两个基因在与感觉和信号转导有关的端足（头）神经元中表现出相似的表达模式。通过异源遗传互补技术对daf-2基因缺陷型菌株进行了进一步的研究。秀丽线虫（CB 1370）显示出Hc-daf-2的部分拯救功能。综上所述，这些发现为Hc-daf-2/Hc-daf-2在H.特别是在向寄生虫的转变过程中。
Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism.