Mitochondria can spawn new ‘organelles’ — hinting at how modern cells evolved

Researchers are discovering that mitochondria (blue), known as cells’ power plants, also play parts in cells’ immune responses. Credit: David M. Phillips/Science Photo Library When a parasite invades a cell, the cell’s mitochondria react by shedding their outer layers to form brand-new cellular compartments — or organelles — that digest molecular trash. Cells are swapping their mitochondria. What does this mean for our health? The team that made the discovery showed that when the mitochondria — best known as cells’ energy producers — form these organelles, it helps the parasite to proliferate, although it isn’t clear exactly how. Maybe the parasite ‘feeds’ off the degraded material inside the tiny compartments, says team leader Lena Pernas, an immunologist at the University of California, Los Angeles. But one thing is certain, Pernas said when presenting the findings at a Keystone symposium on mitochondrial signalling, held in Colorado in February: “Mitochondria are able to give rise to new organelles during infection.” The discovery, posted on 24 April to the preprint server bioRxiv 1 ahead of peer review, adds to a growing list of roles that researchers are uncovering for mitochondria in immunity, including surveilling pathogens 2 and coordinating immune signalling 3 . …