CELLULAR REGULATION OF TYPE III EBV LATENCY

III 型 EBV 潜伏期的细胞调节

基本信息

批准号：
6642890
负责人：
JOSEPH S PAGANO
金额：
$ 43.42万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-08-01 至 2003-07-31
项目状态：
已结题

项目摘要

In the most restricted form of EBV latency, Type I, only EBNA- l is expressed, and only the Q promoter (Qp) is used. EBNA- l is essential for replication of EBV episomes which is synchronized with the cell cycle. We have shown that expression of EBNA- l mRNA is synchronized with cell cycle with little RNA detected in Go and most expressed in S-phase. Here we propose to examine the more complex Type III latency state, in which all of the EBV latency proteins including the principal oncoprotein, LMP-1, are expressed, and promoter usage shifts to C/Wp and promoters for the LMP proteins. We will determine first whether expression of Type III latency genes is linked to cell cycle with a focus on EBNA-2- responsive viral genes (EBNA-l, -2,-3A, -3B, -3C and -LP, LMP-l and -2). We will test the prediction that expression of EBNA-l is also linked to cell cycle in Type III latency. Next we will study phosphorylation of selected Type III latency proteins in the context of cell cycle. Based on preliminary findings, we will verify that EBNA-2 as well as EBNA-LP are phosphorylated in a cell-cycle dependent manner and ask which amino acid residues are phosphorylated and when, and whether mutation of these residues disrupts linkage of phosphorylation of EBNA-2 and LP to cell cycle. Whether there is a consequent effect on LMP-1 will also be studied. Finally, we will determine the functional effects of phosphorylation on the implicated proteins. Little is known about the broader mechanisms whereby latent EBV infection states are regulated and maintained. Moreover, information on the effect of cell cycle on EBV genes is remarkably scant. This work should shed light not only on EBV latency, but also on the EBV transformation process, which may follow when Type III gene products are expressed.

在EBV潜伏期最受限制的形式（I型）中，仅表达EBNA-1，并且仅使用Q启动子（Qp）。 EBNA-1对于与细胞周期同步的EBV附加体的复制是必需的。我们已经表明EBNA-1 mRNA的表达与细胞周期同步，在Go中检测到很少的RNA并且大部分在S期中表达。在这里，我们建议检查更复杂的 III 型潜伏状态，其中所有 EBV 潜伏蛋白（包括主要癌蛋白 LMP-1）均得到表达，并且启动子使用转向 C/Wp 和 LMP 蛋白的启动子。我们将首先确定 III 型潜伏基因的表达是否与细胞周期相关，重点关注 EBNA-2 反应性病毒基因 (EBNA-1、-2、-3A、-3B、-3C 和 -LP、LMP-1)。和-2)。我们将测试 EBNA-1 的表达也与 III 型潜伏期的细胞周期相关的预测。接下来，我们将研究细胞周期背景下选定的 III 型潜伏蛋白的磷酸化。根据初步结果，我们将验证EBNA-2和EBNA-LP以细胞周期依赖性方式磷酸化，并询问哪些氨基酸残基被磷酸化、何时被磷酸化，以及这些残基的突变是否破坏了EBNA磷酸化的连锁-2 和 LP 到细胞周期。还将研究是否对 LMP-1 产生后续影响。最后，我们将确定磷酸化对相关蛋白质的功能影响。对于调节和维持潜伏 EBV 感染状态的更广泛机制知之甚少。此外，关于细胞周期对 EBV 基因影响的信息非常缺乏。这项工作不仅应该揭示 EBV 潜伏期，还应该揭示 EBV 转化过程，该过程可能在 III 型基因产物表达时发生。