Structural Model of the Membrane-Bound C Terminus of Lipid-Modified Human N-Ras Protein

摘要

Covalent lipid modification is a common posttranslational event relevant for 5-10 % of all cellular proteins.[1] In particular, proteins involved in signal transduction are lipidated, providing a hydrophobic anchor that targets these molecules to the membrane.[2] By this mechanism, protein diffusion is constrained to two dimensions, and the probability of interaction with downstream effectors is increased by several orders of magnitude.[3] In spite of the tremendous biological significance of this membrane-binding mechanism, to date no structural data is available for lipidated membrane-bound proteins. Here we report a structural model for the backbone of the membrane-associated lipid-modified C terminus of the Ras protein determined by solid-state magic-angle spinning (MAS) NMR spectroscopy.