Exploring the significance of palmitoylation using an artificial protein lipidation system.

Protein lipidation, particularly palmitoylation (attachment of a 16-carbon fatty acid), regulates cellular behaviors by controlling protein function at lipid membranes. In this study, we prepared a series of lipidated green fluorescent proteins ("EGFP-lipids") with various alkyl chain lengths (C8 to C22). Using model lipid membranes and Jurkat (human T lymphocyte) cells, we evaluated how lipidation affects the membrane interactions and vesicular transport from the membrane of these protein-lipid constructs. Our findings demonstrate that elongation of the alkyl chain profoundly affects both lateral membrane diffusion and vesicular transport of the EGFP-lipids. Only artificially lipidated proteins that mimic lipidation exhibited cellular dynamics in response to external signals, which highlights the significance of the natural selection of palmitic acid to maximize the function of proteins on lipid membranes. This insight can also be useful in membrane engineering using artificial protein lipidation techniques, potentially accelerating medical and industrial developments.