OTK18 Regulation in HIV-1 associated dementia

描述（申请人提供）：转录因子OTK 18，最近已被我们的小组证明可调节单核吞噬细胞（MP）中的HIV-1感染。有趣的是，OTK 18在严重的HIV-1脑炎中特异性表达于脑MP的胞质溶胶中，而在严重的HIV-1脑炎中则不表达。 其他神经退行性疾病，因此可以作为HIV相关痴呆（HAD）发展的“替代”标志物。为了进一步发展这些观察结果，我们将确定为什么OTK 18可以在晚期疾病中以相对高的水平表达，但却不能控制脑靶细胞中的病毒生长。我们的初步数据表明，HIV-1长末端重复序列的E-26 -1结合序列（EBS）是抑制OTK 18的关键元件。EBS也位于OTK 18启动子的近端区域，表明基因表达的自抑制机制。在本申请中，我们假设EBS结合沿着OTK 18内蛋白水解调节HAD中的OTK 18活性。此外，我们将解决疾病中高OTK 18水平之间的差异。及其抗逆转录病毒功能。 我们认为这种明显的矛盾是由于感染的巨噬细胞中OTK 18的内切蛋白水解切割导致其细胞质定位和病毒逃避OTK 18抑制。在这种情况下，病毒逃避OTK 18抑制将与HAD相关。为了检验这些假设，将提出以下问题：1）HIV-1诱导OTK 18表达的机制是什么？2)HAD中病毒抑制OTK 18的机制是什么？，3）OTK 18的内蛋白水解机制是什么？我们认为，OTK 18的分子特征将导致更好地理解MP病毒调控的双重复杂作用及其在HIV-1感染的神经发病机制中的作用。本研究的主要目的是：1）研究OTK-18启动子元件在OTK-18功能中的作用。2)研究HAD中病毒逃避OTK 18抑制的机制，以及3）表征OTK 18加工和功能。拟议的研究是创新的，因为锌精细蛋白的病毒调节和EBS突变对OTK 18抑制的逃逸是一种新的范式。我们 这一发现也可能在锌指分子领域产生重要影响，因为OTK 18位于染色体19 q13上，在那里，逆转录病毒整合位点和锌指簇被整合到染色体19 q13上。 进化上的共同定位

DESCRIPTION (provided by applicant): The transcriptional factor, OTK18, has recently been shown by our group to regulate HIV-1 infection in mononuclear phagocytes (MP). Interestingly, OTK18 is specifically expressed in the cytosol of brain MP in severe HIV-1 encephalitis but not in other neurodegenerative disorders and may thus serve as a "surrogate" marker for the development of HIV-associated dementia (HAD). To further develop these observations we will determine why OTK18 can be expressed at relatively high levels in advanced disease and yet fail to control viral growth in brain target cells. Our preliminary data indicates that the E-twenty six-1 binding sequence (EBS) of the HIV-1 long termminal repeat is a critical element for OTK18 suppression. EBS is also located in the proximal region of the OTK18 promoter, suggesting an autoinhibitory mechanism of gene expression. In this application, we hypothesize that EBS binding along with OTK18 endoproteolysis regulate OTK18 activity in HAD. Furthermore, we will address the discrepency between high OTK18 levels in disease. and its anti-retroviral functions. We believe this apparent contradiction to be due to endoproteolytic cleavage of OTK18 in infected macrophages leading to its cytoplasmic localization and viral escape from OTK18 suppression. In that context, viral escape from OTK18 suppression will correlate with HAD. To examine these hypotheses, the following questions will be asked:1) What is the mechanism(s) for HIV-1 induction of OTK18 expression?, 2) What is the mechanism of viral from OTK18 suppression in HAD?, and 3) What is the mechanism of OTK18 endoproteolysis? We posit that molecular characterization of OTK18 will lead to a better understanding of the dual complex roles of MP viral regulation and its role in the neuropathogensis of HIV-1 infection. We will address the following specific aims; 1) To study the role of promoter elements in OTK-18 function. 2) To study the mechanism of viral escape from OTK18 suppression in HAD, and 3) To characterize OTK18 processing and function. The proposed research is innovative, as viral regulation by a zinc finer protein and escape from OTK18 suppression by EBS mutation is a new paradigm. Our findings may also have an important impact in the field of zinc finger molecules, since OTK18 is located on chromosome 19q13, where clusters of retroviral integration sites and zinc fingers are evolutionally co-localized.