NTA-Cholesterol Analogue for the Nongenetic Liquid-Ordered Phase-Specific Functionalization of Lipid Membranes with Proteins
Yanjun Zheng, Tristan Wegner, Daniele Di Iorio, Marco Pierau, Frank Glorius, Seraphine V. Wegner
Abstract
The nongenetic modification of cell membranes with proteins is a straightforward way of cellular engineering. In these processes, it is important to specifically address the proteins to liquid-ordered (Lo) or liquid-disordered (Ld) domains as this can largely affect their biological functions. Herein, we report a cholesterol analogue (CHIM) with a nitrilotriacetic acid (NTA) headgroup, named CHIM-NTA. CHIM-NTA integrates into lipid membranes similar to the widely used phospholipid-derived DGS–NTA and, when loaded with Ni 2+, allows for specific membrane immobilization of any polyhistidine-tagged proteins of choice. Yet, unlike DGS–NTA, it localizes to the Lo phase in phase-separated giant unilamellar vesicles (GUVs) and allows addressing His-tagged proteins to Lo domains. Furthermore, CHIM-NTA readily integrates into the membranes of live cells and thus enables the nongenetic modification of the cell surface with proteins. Overall, CHIM-NTA provides a facile and flexible way to modify biological membranes, in particular Lo domains, with His-tagged proteins and can serve as a broadly applicable molecular tool for cell surface engineering.