VISUALIZATION OF VACCINIA H1 DUAL-SPECIFICITY PHOSPHATASE WITH STAT1 PEPTIDE

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 在病毒感染后，牛痘H1（VH 1）磷酸酶立即靶向宿主的免疫应答机制，并通过使信号转导蛋白STAT 1去磷酸化而使其失效。这是病毒如何在进化压力下进化生存的一个光辉例子。VH 1的独特之处在于它可以使ser/thr和tyr残基两者去磷酸化，而不像其他磷酸酶那样使一个或另一个去磷酸化。这一类被称为双特异性磷酸酶（DSP），其中VH 1是原型。 初始衍射数据在我们的内部X射线发生器上收集到1.95A。类似的晶体被带到CHESS光束线F1，我们能够收集超过1.3A的数据。这两种结构都已得到解决和完善（PDB ID：2 RF 6和3CEO）。作为该项目的下一步，我们希望用来自转录因子STAT 1的肽浸泡我们的晶体，该转录因子被认为是VH 1的直接底物。STAT 1肽被设计为将STAT 1的区域与磷酸酪氨酸残基结合（701）。我们将晶体浸泡更长时间，并将VH 1与肽共结晶，这应该会产生更强的密度峰。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Upon viral infection Vaccinia H1 (VH1) phosphatase immediately targets the host's immune response mechanism and disables it by dephosphorylating a signal transduction protein, STAT1. This is a shining example of how viruses evolved to survive under evolutionary pressure. VH1 is unique in that it can dephosphorylate both ser/thr and tyr residues, unlike other phosphatases that dephosphorylate one or the other. This class is called dual-specificity phosphatases (DSPs) of which VH1 is the prototype. Initial diffraction data was collected on our in-house xray generator to 1.95A. Similar crystals were taken to the CHESS beamline F1, where we were able to collect data past 1.3A. Both of these structures have been solved and refined( PDB ID: 2RF6 & 3CEO). As the next step in this project, we would like to soak our crystals with a peptide derived from the transcription factor STAT1, which is thought to be a direct substrate of VH1. The STAT1 peptide has been designed to incorporate the region of STAT1 with the phosphotyrosine residue (701). We have soaked the crystals longer and co-crystallized VH1 with the peptide which should give stronger peaks of density.