PDF(Pubmed)
Abstract：
The LAT1-4F2hc complex (SLC7A5-SLC3A2) facilitates uptake of essential amino acids, hormones and drugs. Its dysfunction is associated with many cancers and immune/neurological disorders. Here, we apply native mass spectrometry (MS)-based approaches to provide evidence of super-dimer formation (LAT1-4F2hc)2. When combined with lipidomics, and site-directed mutagenesis, we discover four endogenous phosphatidylethanolamine (PE) molecules at the interface and C-terminus of both LAT1 subunits. We find that interfacial PE binding is regulated by 4F2hc-R183 and is critical for regulation of palmitoylation on neighbouring LAT1-C187. Combining native MS with mass photometry (MP), we reveal that super-dimerization is sensitive to pH, and modulated by complex N-glycans on the 4F2hc subunit. We further validate the dynamic assemblies of LAT1-4F2hc on plasma membrane and in the lysosome. Together our results link PTM and lipid binding with regulation and localisation of the LAT1-4F2hc super-dimer.
摘要：
LAT1-4F2hc复合物（SLC7A5-SLC3A2）促进必需氨基酸的摄取，激素和药物。其功能障碍与许多癌症和免疫/神经障碍有关。这里,我们应用基于天然质谱（MS）的方法来提供超二聚体形成的证据（LAT1-4F2hc）2。当与脂质组学结合时，和定点诱变，我们在两个LAT1亚基的界面和C末端发现了四个内源性磷脂酰乙醇胺（PE）分子。我们发现，界面PE结合受4F2hc-R183调节，对于调节相邻LAT1-C187的棕榈酰化至关重要。将天然MS与质量测光（MP）相结合，我们发现超级二聚化对pH敏感，并由4F2hc亚基上的复合N-聚糖调节。我们进一步验证了LAT1-4F2hc在质膜和溶酶体上的动态组装。我们的结果一起将PTM和脂质结合与LAT1-4F2hc超二聚体的调节和定位联系起来。
