Cellular responses to human metapneumovirus infection

描述（由申请人提供）：我的长期职业目标是研究呼吸道病毒感染发病机制的病毒和宿主特异性机制，以开发新的治疗干预措施，以及可行的候选疫苗。K22奖将帮助我，为我建立独立调查员的职业生涯提供必要的初步支持。人偏肺病毒（hMPV）是最近发现的一种属于副粘病毒科的呼吸道病毒。它是儿童呼吸道感染的主要原因。关于hMPV感染的发病机制的信息很少。本研究的目的是利用分子病毒学、细胞生物学和蛋白质化学技术的结合来研究宿主细胞对hMPV感染的反应。我最近的研究表明，RNA解旋酶- mavs信号通路在hmpv诱导的免疫和炎症基因表达中起着重要作用，包括I型干扰素和趋化因子，它们通过核因子-？B (NF - ?B)和干扰素调节因子（IRF）转录因子。初步研究表明，hMPV糖蛋白G和小疏水蛋白SH可能通过破坏RIG-I和pka依赖的信号传导来调节hMPV诱导的细胞反应。本提案的目标是确定宿主信号分子与病毒蛋白之间的分子相互作用，并将通过以下具体目标来完成：目的1。明确G抑制rig -l介导的信号转导的分子机制。为此，我们将研究G蛋白表达是否通过破坏rig - 1与其下游接头MAVS的关联和/或从rig - 1中分离病毒RNA来干扰rig - 1依赖性信号。我们还将确定G的哪些残基对调节hmpv诱导的细胞信号传导是重要的。目标2。确定SH抑制NF-?的分子机制B激活。为此，我们将首先确定SH抑制NF-？B磷酸化。然后，我们将绘制对其抑制活性至关重要的SH残基。相关性（见说明）：在完成拟议的研究后，我们将获得关于hmpv诱导的细胞信号传导机制的新的关键信息，这可能使我们能够特异性地调节病毒诱导的基因表达，从而调节抗病毒和先天免疫/炎症反应。从这些研究中获得的结果将有助于未来开发安全有效的hMPV候选疫苗。

DESCRIPTION (provided by applicant): My long-term career goal is to investigate viral- and host-specific mechanisms that contribute to the pathogenesis of respiratory viral infections, in order to develop novel therapeutic intervention, as well as viable vaccine candidates. The K22 award will help me by providing the initial support necessary to establish a career as an independent investigator. Human metapneumovirus (hMPV) is a recently identified respiratory virus belonging to the Paramyxoviridae family. It is a leading cause of respiratory infections in children. Little information is available regarding the pathogenesis of hMPV infection. The aim of this proposal is to investigate host cellular responses to hMPV infection using a combination of molecular virology, cellular biology and protein chemistry techniques. I have recently shown that the RNA helicases-MAVS signaling pathway plays a significant role in hMPV-induced expression of immune and inflammatory genes, including type I interferon and chemokines, which are regulated through the activation of Nuclear Factor-? B (NF-?B) and Interferon Regulatory Factors (IRF) transcription factors. Preliminary studies demonstrated that hMPV glycoprotein G and small hydrophobic protein SH modulate hMPV-induced cellular responses by likely disrupting RIG-I- and PKA-dependent signaling. The goal of this proposal is to identify molecular interaction between host signaling molecules and viral proteins and will be accomplished through the following specific aims: Aim 1. To define the molecular mechanism whereby G inhibits RIG-l-mediated signaling. In this aim, we will investigate whether G protein expression interferes with RIG-I dependent signaling by disrupting the association of RIG-I with its downstream adaptor MAVS and/or by sequestering viral RNA from RIG-I. We will also identify which residues of G are important for modulating hMPV-induced cellular signaling. Aim 2. To define the molecular mechanism whereby SH inhibits NF-?B activation. In this aim, we will first determine the mechanism by which SH inhibits NF-?B phosphorylation. We will then map SH residue(s) critical for its inhibitory activity. RELEVANCE (See instructions): Upon completion of the proposed studies, we will obtain new critical information on the mechanisms of hMPV-induced cellular signaling, which may allow us to specifically modulate viral-induced gene expression and therefore antiviral and innate immune/inflammatory responses. The results obtained from these studies will be instrumental for the development of future hMPV vaccine candidates which are safe and effective.