Dehydroamino acids in HIV-1 capsid and matrix proteins: new potential targets for viral inactivation

项目概要/摘要 我们最近在衣壳和基质蛋白中发现了脱氢氨基酸（DHAAs）， HIV-1病毒粒子。这些脱氢丙氨酸（DHA）和脱氢丁酸（DHB）残基由翻译后 丝氨酸、苏氨酸或半胱氨酸残基的修饰。我们建议在这里调查的重要性和 这些迷人的蛋白质修饰的起源。它们在这些病毒蛋白中的高流行率， 与它们在人类蛋白质组中的低水平相比，提出了两个关键问题：a）它们为什么存在？ 以及B）它们是如何到达那里的？我们假设DHAA存在于病毒体中，因为它们在病毒中起重要作用， 在HIV病毒体组装或衣壳成熟中的作用。我们进一步假设DHAA是由一种 病毒或宿主蛋白中目前未知的酶活性。 为了验证这些假设，我们将进行突变和失活研究的氨基酸转化为 脱氢氨基酸，并研究对病毒复制周期和感染性的影响。我们将使用定量 蛋白质组学，以确定有多少这种修饰是产生的，以及它是在病毒之前还是之后， 成熟我们将寻求发现分子内或分子间的蛋白质交联，其中脱氢氨基酸是 已知能够形成，使用创新的蛋白质组学方法。此外，我们将寻求发现 酶负责这些修饰的形成。这种酶的发现 DHAA的形成将是有趣的基础生物学，提供新的见解艾滋病毒复制， 这可能揭示了治疗HIV感染的新的治疗途径。

Project Summary/Abstract We have recently discovered dehydroamino acids (DHAAs) in the capsid and matrix proteins that make up HIV-1 virions. These dehydroalanine (DHA) and dehydrobutyrine (DHB) residues result from posttranslational modification of serine, threonine, or cysteine residues. We propose here to investigate the importance and origin of these fascinating protein modifications. Their high prevalence in these viral proteins, in marked contrast to their low levels in the human proteome generally, raises two key questions: a) why are they there? and b) how did they get there? We hypothesize that DHAAs are present in virions because they play important roles in the HIV virion assembly or capsid maturation. We hypothesize further that DHAAs are formed by a presently unknown enzymatic activity in viral or host proteins. To test these hypotheses, we will conduct mutation and inactivation studies of the amino acids that convert to dehydroamino acids and study the effects on the viral replication cycle and infectivity. We will use quantitative proteomics to determine how much of this modification is generated and whether it is before or after viral maturation. We will seek to discover intra- or intermolecular protein crosslinks, which dehydroamino acids are known to be able to form, using innovative proteomics approaches. Further, we will seek to discover the enzyme responsible for the formation of these modifications. The discovery of the enzyme responsible for DHAA formation would be interesting as fundamental biology, offer new insights into HIV replication, and potentially reveal a new therapeutic pathway for the treatment of HIV infection.