Lymphocyte antigen 6E/LY6E Protein, Human (His-SUMO)

LY6E, a glycosylphosphatidylinositol (GPI)-anchored cell surface protein, serves as a key regulator of T-lymphocyte proliferation, differentiation, and activation. Functionally, it modulates T-cell receptor (TCR) signaling by interacting with the CD3Z/CD247 component at the plasma membrane, thereby influencing the phosphorylation status of CD3Z/CD247. Additionally, LY6E plays a critical role in restricting the entry of human coronaviruses, including SARS-CoV, MERS-CoV, and SARS-CoV-2, by disrupting spike protein-mediated membrane fusion. Notably, it acts as the primary receptor for syncytin-A (SynA), contributing to placenta formation by facilitating the fusion of syncytiotrophoblast layer I (SynT-I) and ensuring proper morphogenesis of fetal and maternal vasculatures within the placenta. Furthermore, LY6E may function as a modulator of nicotinic acetylcholine receptors (nAChRs) activity. In the context of microbial infection, LY6E both facilitates and restricts viral entry, enhancing the fusion process for various viruses, including HIV-1, West Nile virus, dengue virus, and Zika virus, while being dispensable for the paramyxovirus PIV5 that enters at the plasma membrane. Mechanistically, LY6E adopts a microtubule-like organization upon viral infection, contributing to enhanced viral uncoating following endosomal escape.