Choline-containing phospholipids e.g. phosphatidylcholine or sphingomyelin are a class of lipids that are major components of cell membranes. They are critical for structural membrane integrity & signaling as well as celluar metabolism. Hence, the dynamics of choline-containing phospholipid synthesis is an essential parameter to analyze the cellular response under both physiological and pathological conditions.
Jao et al.[1,2] and Caishun et al. reported a Click Chemistry-based approach to label newly synthesized choline-containing phospholipids in cell culture and whole organisms: The choline analogs Propargyl-choline (PCho) and 1-Azidoethyl-choline (AECho) are cell-permeable and metabolically incorporated into all classes of choline-containing phospholipids via the CDP-choline pathway.
 Jao et al. (2009) Metabolic Labeling and direct imaging of choline phospholipids in vivo. PNAS 106 (36):15332.
 Jao et al. (2015) Biosynthetic Labeling and Two-Color Imaging of Phospholipids in Cells. Chem. Bio. Chem. 16:472.
 Caishun et al. (2014) Practical Labeling Methodology for Choline-derived Lipids and Applications in Live Cell Fluorescence Imaging. Photochemistry and Photobiology 90:686.