A Walk in the Garden of Forking Paths

In the framework of our GHI Floor Seminars, we are happy to host Giovanni D'Angelo (Lipid Cell Biology Laboratory – Kristian Gerhard Jebsen Chair on Metabolism).

COVID-19: the talk will be held in SV 1717 but allow a maximum of 30 people to attend the seminar, on a first come first served basis. Mask is mandatory. The talk will be streamed via Zoom to allow everyone else to participate. If you are not a GHI member and wish to attend the seminar, please register following this link: https://epfl.zoom.us/meeting/register/tJAkfuyoqzsqEtxFujqV5KheYMCUrcg31IiS

A Walk in the Garden of Forking Paths
Abstract:
Eukaryotic cells produce thousands of lipids that contribute to specific biological functions. Thanks to lipidomics, we now appreciate the lipid compositional dynamics of the cell. Lipidomes indeed vary among cell types and change in differentiation events. Lipid composition also changes from cell to cell in otherwise homogeneous populations contributing to cell heterogeneity. So far, biologists have addressed lipidomes in bulk cell extracts or selected lipids at the single-cell level. Thus, which cell-to-cell lipid variations have biological meaning remains largely undefined. Here, by using high-resolution mass spectrometry imaging, we have analyzed the lipidome of hundreds of individual human dermal fibroblasts in situ. We found that: (i) specific lipid metabolic segments (i.e., the sphingolipid pathways) are cell-to-cell variable; (ii) given lipid configurations mark discrete cell states; (iii) and that sphingolipids modulate dermal fibroblast activation involved in skin development and wound healing . These data uncover a role for lipid heterogeneity in the determination of cell states and in tissue homeostasis and reveal a new regulatory component to the self-organization of multicellular systems.