Live-cell lipid biochemistry reveals a role of diacylglycerol side-chain composition for cellular lipid dynamics and protein affinities
| Autor: | Milena Schuhmacher, Ünal Coskun, Pia Sala, Alexander M. Walter, J.S. Schuhmacher, André Nadler, Pavel Barahtjan, Ian Henry, Andrej Shevchenko, Benoit Lombardot, Nicolai Wagner, Annett Lohmann, Andreas T. Grasskamp |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
010402 general chemistry
01 natural sciences Biochemistry Diglycerides 03 medical and health sciences Signaling Lipids Diacylglycerol Protein Kinase C Mathematical Modeling Caged Lipid Probes Protein kinase C Lipid Biochemistry 030304 developmental biology Diacylglycerol kinase 0303 health sciences Multidisciplinary diacylglycerol Chemistry mathematical modeling signaling lipids Biological Sciences Lipid Metabolism Affinities Lipids 0104 chemical sciences Diacylglycerol binding Second messenger system Physical Sciences Lipidomics Biophysics Phosphorylation lipids (amino acids peptides and proteins) caged lipid probes Function (biology) protein kinase C |
| Zdroj: | Proceedings of the National Academy of Sciences of the United States of America Proceedings of the National Academy of Sciences Proc. Natl. Acad. Sci. U.S.A. 117, 7729-7738 (2020) |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | Significance Every cell produces thousands of lipid species, but studying the function of individual lipids in living cells is almost impossible with existing methodologies. Addressing this experimental bottleneck, we developed a strategy to quantify dissociation constants for lipid–protein interactions and transmembrane flip-flop rates of native lipids in live-cell experiments. Using a combination of plasma membrane-specific photochemical probes and mathematical modeling, we demonstrate that, for diacylglycerols as a model lipid class, the inherent lipid structural diversity caused by variations in acyl chain composition determines lipid protein affinities and transbilayer kinetics. In fact, subtle chemical differences change these values by orders of magnitude. Our approach represents a generally applicable method for elucidating the biological function of single lipid species on subcellular scales. Every cell produces thousands of distinct lipid species, but insight into how lipid chemical diversity contributes to biological signaling is lacking, particularly because of a scarcity of methods for quantitatively studying lipid function in living cells. Using the example of diacylglycerols, prominent second messengers, we here investigate whether lipid chemical diversity can provide a basis for cellular signal specification. We generated photo-caged lipid probes, which allow acute manipulation of distinct diacylglycerol species in the plasma membrane. Combining uncaging experiments with mathematical modeling, we were able to determine binding constants for diacylglycerol–protein interactions, and kinetic parameters for diacylglycerol transbilayer movement and turnover in quantitative live-cell experiments. Strikingly, we find that affinities and kinetics vary by orders of magnitude due to diacylglycerol side-chain composition. These differences are sufficient to explain differential recruitment of diacylglycerol binding proteins and, thus, differing downstream phosphorylation patterns. Our approach represents a generally applicable method for elucidating the biological function of single lipid species on subcellular scales in quantitative live-cell experiments. |
| Databáze: | OpenAIRE |
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