Regulation of cellular functions by two human Polyomaviruses

 描述(申请人提供)：多瘤病毒基因组很小，编码能力非常有限。为了编码病毒DNA复制、转录控制和宿主功能操纵所需的功能，多瘤病毒表达一系列编码T抗原的早期mRNA的选择性剪接形式。所有多瘤病毒都编码一个多功能的大T抗原(LT)，大多数病毒编码一个小T抗原(ST)，以及一系列额外的、特征不佳的早期蛋白。在从人类分离的13种多瘤病毒中，有几种同时表达LT和ST，其功能似乎与经过充分研究的猿猴病毒40(SV40)相似。然而，其他人类多瘤病毒在其LT和ST蛋白的结构和生物活性方面与SV40非常不同。其中包括最近发现的新泽西州多瘤病毒(NJPyV)和人类多瘤病毒9(HuPyV9)。在这一探索性应用中，我们试图揭示NJPyV和HuPyV9 T抗原的独特生物学特性。具体地说，我们将确定由NJPyV编码的替代T抗原(AT)是否实际上是真正的中T抗原(MT)。到目前为止，仅有的表达MT蛋白的多瘤病毒，小鼠多瘤病毒和仓鼠多瘤病毒感染啮齿动物。因此，找到一种表达MT的人类病毒将是非常新颖的，并表明独特的宿主操纵功能。此外，我们将确定来自LPV的LT和ST如何能够独立地使细胞永生并诱导细胞增殖，并将确定这些蛋白强大协同作用的分子基础。LPV是一种与HuPyV9密切相关的灵长类多瘤病毒。我们没有重复过去用来表征T抗原的常用方法，而是开发了新的策略，旨在有效地从RNA-Seq数据中识别由T抗原改变的细胞路径，然后将这种方法与更传统的遗传学和蛋白质组学相结合。使用这一策略，我们可以确定HuPyV9是否改变了与SV40和其他类似多瘤病毒相同的细胞通路，或者该病毒是否通过新的机制操纵细胞功能。

 DESCRIPTION (provided by applicant): Polyomaviruses have small genomes and their coding capacity is very limited. In order to encode for functions needed in viral DNA replication, transcriptional control, and the manipulation of host functions, polyomaviruses express a series of alternatively spliced forms of their early mRNA that encode T antigens. All polyomaviruses encode a multifunctional large T antigen (LT) and most encode a small T antigen (ST), plus a series of additional poorly characterized early proteins. Of the thirteen polyomaviruses that have been isolated from humans, several express both an LT and ST that appear to be similar in function to those of the well-studied Simian virus 40 (SV40). However, other human polyomaviruses are quite distinct from SV40 regarding both the structure and biological activities of their LT and ST proteins. These include the recently discovered New Jersey polyomavirus (NJPyV) and Human polyomavirus 9 (HuPyV9). In this exploratory application we seek to uncover the unique biology of the NJPyV and HuPyV9 T antigens. Specifically, we will determine whether an alternative T antigen (AT) encoded by NJPyV is in fact an authentic middle T antigen (MT). Thus, far the only polyomaviruses that express a MT protein, murine polyomavirus and hamster polyomavirus, infect rodents. Thus, finding a human virus that expresses a MT would be very novel and suggest unique host manipulation functions. In addition, we will determine how the LT and ST from LPV, a primate polyomavirus closely related to HuPyV9- are able to independently immortalize cells and induce cell proliferation, and will also determine the molecular basis for the robust synergistic action of these proteins. Rather than recapitulate the well-trodden path that has been used to characterize T antigens in the past, we have developed new strategies designed to efficiently identify cellular pathways altered by T antigens from RNA-Seq data, and then to couple this approach with more traditional genetics and proteomics. Using this strategy, we can determine whether HuPyV9 alters the same cellular pathways as SV40 and other similar polyomaviruses, or if this virus manipulates cellular functions by novel mechanisms.