Molecular cloning and DNA binding characterization of DAF-16 orthologs from Ancylostoma hookworms.
Molecular cloning and DNA binding characterization of DAF-16 orthologs from Ancylostoma hookworms.
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DOI：
10.1016/j.ijpara.2008.09.005
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发表时间：
2009-03
影响因子：
4
通讯作者：
Hawdon JM
中科院分区：
文献类型：
--
作者：
Gao X;Frank D;Hawdon JM
感染性钩虫L3在感染期间遇到宿主特异性信号，重新启动暂停的发育途径，导致发育到成虫阶段。这种恢复在主机的发展是类似的恢复发育停滞秀丽隐杆线虫Dauer幼虫响应有利的环境信号。Dauer恢复率在C. elegans dauers和钩虫L3 s的表达是由胰岛素样信号传导（ILS）介导的。ILS在C中的关键输出。在线虫中，一种重要的转录因子是叉头转录因子β-16，它控制着维持Dauer期所需的基因的表达。L3和dauers的恢复途径之间的相似性表明，α-16在钩虫L3激活中的功能相似。为了测试这一点，从钩虫Ancylostoma caninum和Ancylostoma ceylanicum中分离Ce-III-16的直系同源物。钩虫Ce 16 DNA结合域的蛋白质序列是相同的，并且与Ce 16的B和c同种型共享94%的同一性。在HEK 293肾细胞中表达的Ac-Arg-16强烈结合保守的Arg家族结合元件（DBE），但不结合随机DNA序列。在饥饿的条件下，Ac-BBE-16能够驱动位于NIH 3 T3细胞中DBE的六个拷贝下游的报告基因的转录。血清的加入导致报告基因表达的减少，表明生长因子的刺激负调控α-16。这些数据证实了钩虫中存在Δ C-16直系同源物，并证明Ac-Δ C-16结合保守的Δ C-16家族DNA结合元件并驱动转录。
Infective hookworm L3s encounter a host-specific signal during infection that re-initiates a suspended developmental pathway, resulting in development to the adult stage. This resumption of development in the host is analogous to recovery of developmentally arrested Caenorhabditis elegans dauer larvae in response to favorable environmental signals. Dauer recovery in C. elegans dauers and hookworm L3s is mediated by insulin-like signaling (ILS). A key output of ILS in C. elegans is the forkhead transcription factor DAF-16, which controls the expression of genes required for maintenance of the dauer stage. The similarity between recovery pathways of L3s and dauers suggests that DAF-16 functions similarly in hookworm L3 activation. To test this, orthologs of Ce-DAF-16 were isolated from the hookworms Ancylostoma caninum and Ancylostoma ceylanicum. The protein sequences of hookworm DAF-16 DNA binding domains were identical, and shared 94% identity with the b and c isoforms of Ce-DAF-16. Ac-DAF-16 expressed in HEK293 kidney cells bound strongly to the conserved DAF family binding element (DBE), but not to a random DNA sequence. Ac-DAF-16 was able to drive transcription of a reporter gene located downstream of six copies of the DBE in NIH3T3 cells under starved conditions. Addition of serum caused a decrease in reporter gene expression, indicating that DAF-16 is negatively regulated by growth factor stimulation. These data confirm the presence of DAF-16 orthologs in hookworms, and demonstrate that Ac-DAF-16 binds to and drives transcription from a conserved DAF-16 family DNA binding element.
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影响因子：
64.5
作者：
Brunet, A;Bonni, A;Greenberg, ME
通讯作者：
Greenberg, ME
影响因子：
2.7
作者：
Estevez, Annette O.;Cowie, Robin H.;Estevez, Miguel
通讯作者：
Estevez, Miguel
影响因子：
2.4
作者：
GARSIDE, P;BEHNKE, JM
通讯作者：
BEHNKE, JM
DOI：
10.1073/pnas.89.18.8754
发表时间：
1992-09-15
影响因子：
11.1
作者：
HACKER, U;GROSSNIKLAUS, U;JACKLE, H
通讯作者：
JACKLE, H
影响因子：
4
作者：
Brand, A;Hawdon, JM
通讯作者：
Hawdon, JM