Exploring the links between lipid geometry and mitochondrial fission: Emerging concepts.

Mitochondria, the double membrane-walled powerhouses of the eukaryotic cell, are also the seats of synthesis of two critical yet prevalent nonbilayer-prone phospholipids, namely phosphatidylethanolamine (PE) and cardiolipin (CL). Besides their established biochemical roles in the regulation of partner protein function, PE and CL are also key protagonists in the biophysics of mitochondrial membrane remodeling and dynamics. In this review, we address lipid geometry and behavior at the single-molecule level as well as their intimate coupling to whole organelle morphology and remodeling during the concerted events of mitochondrial fission. We present evidence from recent experimental measurements ably supported and validated by computational modeling studies to support our notion that conical lipids play a catalytic as well as a structural role in mitochondrial fission.