The matrix (MA) domain of the HIV-1 precursor Gag protein (PrGag) has been shown interact with the HIV-1 envelope (Env) protein, and to direct PrGag proteins to plasma membrane (PM) assembly sites by virtue of its affinity to phosphatidylinositol-4,5-bisphosphate (PI[4,5]P2). Unexpectedly, HIV-1 viruses with large MA deletions (ΔMA) have been shown to be conditionally infectious as long as they are matched with Env truncation mutant proteins or alternative viral glycoproteins. To characterize the interactions of wild type (WT) and ΔMA Gag proteins with PI(4,5)P2 and other acidic phospholipids, we have employed a set of lipid biosensors as probes. Our investigations showed marked differences in WT and ΔMA Gag colocalization with biosensors, effects on biosensor release, and association of biosensors with virus-like particles. These results demonstrate an alternative approach to the analysis of viral protein-lipid associations, and provide new data as to the lipid compositions of HIV-1 assembly sites.

中文翻译：

---

脂质生物传感器与野生型和基质缺失HIV-1 Gag蛋白的相互作用。

HIV-1前体Gag蛋白（PrGag）的基质（MA）结构域已显示与HIV-1包膜（Env）蛋白相互作用，并凭借其亲和力将PrGag蛋白引导至质膜（PM）组装位点磷脂酰肌醇-4,5-二磷酸（PI [4,5] P2）。出乎意料的是，具有较大MA缺失（ΔMA）的HIV-1病毒已被证明具有条件感染性，只要它们与Env截短突变蛋白或其他病毒糖蛋白匹配即可。为了表征野生型（WT）和ΔMAGag蛋白与PI（4,5）P2和其他酸性磷脂的相互作用，我们采用了一组脂质生物传感器作为探针。我们的研究表明，WT和ΔMAGag与生物传感器共定位，对生物传感器释放的影响以及生物传感器与病毒样颗粒的缔合存在显着差异。