ProjectWhy are polyunsaturated lipids special?
About
Classical cell lines allow us to study basic functions, such as vesicular trafficking or membrane contact sites. However, the lipids in these cells do not reflect the diversity found in differentiated tissues. Depending on the cell or organelle type, membranes exhibit very different ratios of saturated, monounsaturated, and polyunsaturated lipids. By adjusting the unsaturation profiles of cell membranes or model membranes, we aim to understand the properties conferred by polyunsaturated phospholipids. We have shown that lipids containing a DHA chain, the most polyunsaturated fatty acid in the omega-3 family, make membranes extremely flexible and thus suitable for rapid endocytosis. This finding suggests a link between the abundance of polyunsaturated lipids in synaptic vesicles and ultrafast endocytosis in neurons. We imagine that other cellular or tissue properties (for example, cell permeability, sensitivity to bacterial toxins, progression of neurodegenerative diseases…) could depend on the unsaturation profile of their membranes, and in particular on the ratio between omega-3 and omega-6 lipids.
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| Biological membranes have very different levels of lipid unsaturation. | Polyunsaturated phospholipids change the membrane order |
Coarse-grained molecular dynamics simulations show that polyunsaturated lipids facilitate membrane deformation.