Enrichment of Cysteine S-palmitoylated peptides using Sodium Deoxycholate Acid Precipitation.

Abstract

S-palmitoylation is a poorly understood post-translational modification that is gaining more attention as an essential regulator of cellular processes. The reversible nature of S-palmitoylation may allow for fine-tuned control of cellular events and adaptation to stimuli. The detection of S-palmitoylated proteins and peptides includes the Acyl-Biotin Exchange (ABE) method, Acyl resin-assisted Capture (Acyl-RAC), metabolic labelling, and derivatives thereof. We present a novel method of enrichment of S-palmitoylated peptides termed SDC Acid Precipitation Enrichment (SDC-ACE). Here, S-palmitoylated peptides are enriched by taking advantage of their co-precipitation with Sodium-Deoxycholate (SDC) under acidic conditions, allowing easy and fast separation of lipidated peptides from the sample suspension. We initially applied our novel method for the characterization of the mouse brain, providing an in-depth analysis of S-palmitoylation events within the brain and comprehensive profile of the mouse brain S-palmitoylome. Further, we applied our method for mapping mouse tissue-specific S-palmitoylation, highlighting the extensive role of S-palmitoylation throughout various organs in the body. Finally, we applied our methods for studying the brain palmitoylome of diabetic db/db mouse, uncovering alterations in the palmitoylation of proteins associated with obesity and type 2 diabetes. The SDC-ACE method allows fast and easy enrichment of S-palmitoylated peptides, providing a valuable tool for exploring the dynamics and function of S-palmitoylation in diverse biological systems.