Quantification of phosphoinositides reveals strong enrichment of PIP2 in HIV-1 compared to producer cell membranes
Quantification of phosphoinositides reveals strong enrichment of PIP2 in HIV-1 compared to producer cell membranes
复制标题
DOI：
10.1038/s41598-019-53939-z
复制
发表时间：
2019-11-27
影响因子：
4.6
通讯作者：
Kraeusslich, Hans-Georg
中科院分区：
文献类型：
--
作者：
Muecksch, Frauke;Citir, Mevlut;Kraeusslich, Hans-Georg
人类免疫缺陷病毒1型（HIV-1）在宿主细胞质膜出芽期间获得其脂质包膜。各种研究表明，HIV-1膜不同于生产细胞质膜，表明从专门的膜微区出芽。磷酸肌醇PI（4，5）P-2特别令人感兴趣，因为需要PI（4，5）P2将病毒结构多聚蛋白Gag募集到质膜，从而促进病毒形态发生。虽然有证据表明PIP 2在HIV-1中富集，但所有磷酸肌醇的完全定量分析仍然具有技术挑战性，因此尚未报道。在这里，我们提出了一个全面的分析的脂质含量的HIV-1和质膜从感染和未感染的生产细胞，导致总共478个量化的脂质化合物，包括25个不同的脂质类的分子种类分布。磷酸肌醇的定量分析显示，与生产细胞质膜相比，PIP 2和PIP 3在病毒中强烈富集。我们计算了一个平均值。每个HIV-1粒子有8,000个PIP 2分子，是Gag的三倍。我们推测，高密度的PIP 2在HIV-1的装配网站介导的瞬时相互作用与病毒Gag多聚蛋白，促进PIP 2浓度在这个微域。这些结果与我们先前的观察一致，即PIP 2不仅是募集所需的，而且也是在质膜上稳定维持Gag所需的。我们相信，这种定量分析的HIV-1脂质包膜的分子解剖学可以作为标准的参考，为今后的调查。
Human immunodeficiency virus type 1 (HIV-1) acquires its lipid envelope during budding from the plasma membrane of the host cell. Various studies indicated that HIV-1 membranes differ from producer cell plasma membranes, suggesting budding from specialized membrane microdomains. The phosphoinositide PI(4,5)P-2 has been of particular interest since PI(4,5)P2 is needed to recruit the viral structural polyprotein Gag to the plasma membrane and thus facilitates viral morphogenesis. While there is evidence for an enrichment of PIP2 in HIV-1, fully quantitative analysis of all phosphoinositides remains technically challenging and therefore has not been reported, yet. Here, we present a comprehensive analysis of the lipid content of HIV-1 and of plasma membranes from infected and non-infected producer cells, resulting in a total of 478 quantified lipid compounds, including molecular species distribution of 25 different lipid classes. Quantitative analyses of phosphoinositides revealed strong enrichment of PIP2, but also of PIP3, in the viral compared to the producer cell plasma membrane. We calculated an average of ca. 8,000 PIP2 molecules per HIV-1 particle, three times more than Gag. We speculate that the high density of PIP2 at the HIV-1 assembly site is mediated by transient interactions with viral Gag polyproteins, facilitating PIP2 concentration in this microdomain. These results are consistent with our previous observation that PIP2 is not only required for recruiting, but also for stably maintaining Gag at the plasma membrane. We believe that this quantitative analysis of the molecular anatomy of the HIV-1 lipid envelope may serve as standard reference for future investigations.