BIOLOGY OF MAMMALIAN HOMEODOMAIN PROTEINS

单纯疱疹病毒是一种重要的人类病原体， 从轻微的复发性生殖器或面部损伤到致命的疾病 新生儿感染。 据推测，在体内， HSV-1的立即早期（IE）基因的调控可能控制HSV-1的表达。 感染的严重程度以及感染是否会通过溶解性或 保持潜伏状态，以确定细胞内宿主和病毒因子 可能控制IE基因在体内的表达，我们已经专注于 能够与TAATGARAT调节区相互作用的蛋白质 IE基因。 我们之前已经发现，在体外，小鼠同源结构域 Hox 1.3蛋白结合 TAATGARAT图案。 为了测试Hox 1.3的过表达是否会改变 HSV-1的发病机制，我们产生了转基因小鼠，其中的水平， Hox 1.3受病毒感染的调节（通过响应病毒感染）。 病毒/干扰素诱导型启动子）。 这种转基因小鼠确实是 明显更容易受到裂解性HSV-1感染，最有可能是因为 Hox 1.3蛋白在被感染的细胞中被诱导， 接触HSV-1。 为了研究这是否增加了对 HSV-1是由于Hox 1.3对IE基因调控的直接作用。 区域，我们已经产生了额外的转基因小鼠，表达 IE基因启动子下的细菌β-半乳糖苷酶报告基因， 我们将这些小鼠与Hox 1.3转基因小鼠杂交。 双转基因 在小鼠中，我们将用干扰素诱导Hox 1.3蛋白， 这种诱导将导致报告基因的反式激活。 在 此外，我们已经产生了转基因小鼠，它们携带了一个cDNA， 截短形式的病毒VP 16蛋白，其不能 反式激活IE基因，但能够与野生型VP 16竞争。 这些 已经在HSV-1易感背景下扩大了小鼠品系， 将准备好测试HSV-1过程中的变化 感染和潜伏期在不久的将来。 该项目将继续进行 米切尔博士在LNEP。

Herpes simplex virus is an important human pathogen associated with diseases ranging from mild recurrent genital or facial lesions to fatal infections of newborns. It has been postulated that in vivo, the regulation of the immediate early (IE) genes of HSV-1 may control the severity of an infection and whether the infection will by lytic or remain latent, In order to define intracellular host and viral factors that might control IE gene expression in vivo, we have focused on proteins capable of interacting with the TAATGARAT regulatory regions of IE genes. We have found earlier that in vitro, the mouse homeodomain protein Hox 1.3 binds TAATGARAT motifs. To test whether overexpression of Hox 1.3 would alter HSV-1 pathogenesis, we generated transgenic mice in which the level of Hox 1.3 is regulated by virus infection (by way of responding to a virus/interferon-inducible promoter). Such transgenic mice are indeed markedly more susceptible to lytic HSV-1 infection, most likely because Hox 1.3 protein is induced in the very cells that become infected upon exposure to HSV-1. To study whether this increased susceptibility to HSV-1 is due to a direct action of Hox 1.3 on the IE gene regulatory region, we have generated additional transgenic mice that express the bacterial beta-galactosidase reporter gene under an IE gene promoter and we crossed these mice with the Hox 1.3 transgenics. In double transgenic mice, we will induce the Hox 1.3 protein with interferon and test whether this induction would result in transactivation of the reporter gene. In addition, we have generated transgenic mice that harbor a cDNA for a truncated form of the viral VP16 protein that is incapable to transactivate IE genes but capable to compete with wild type VP16. These lines of mice have been expanded on a HSV-1 susceptible background and will become ready to test for alterations in the course of HSV-1 infection and latency in the near future. This project will be continued by Dr. Mitchell in LNEP.