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

项目摘要/摘要 我们最近在衣壳和基质蛋白中发现了脱氢氨基酸(DHAAs)，这些蛋白质组成了 HIV-1病毒粒子。这些脱氢丙氨酸(DHA)和脱氢丁碱(DHB)残基是由翻译后 丝氨酸、苏氨酸或半胱氨酸残基的修饰。我们建议在此调查 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，在标记的 与它们在人类蛋白质组中的低水平相比，它提出了两个关键问题：a)它们为什么存在？ B)他们是如何做到这一点的？我们假设DHAAs存在于病毒粒子中，因为它们发挥着重要的作用 在HIV病毒粒子组装或衣壳成熟中的作用。我们进一步假设DHAA是由一个 目前尚不清楚病毒或宿主蛋白中的酶活性。 为了验证这些假设，我们将对转化为 脱氢氨基酸，并研究对病毒复制周期和传染性的影响。我们将使用量化 蛋白质组学来确定这种修饰产生了多少，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链，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，我们将努力发现 负责形成这些修饰的酶。这种酶的发现导致了 DHAA的形成将是有趣的基础生物学，为艾滋病毒复制提供新的见解，以及 潜在地揭示了一种治疗艾滋病毒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.