It started with a picture,” says University of Colorado Boulder molecular and cellular biologist Gia Voeltz. When she was still a postdoc, Voeltz and her colleagues started painstakingly assembling 3-D electron microscopy and tomography images of the endoplasmic reticulum (ER) in hopes of locating a structural protein on its surface.
But as soon as they had the assembled images, “we started to get a glimpse of all these interactions” of the ER with other organelles, most notably with mitochondria, and their interest in reticulin proteins fell by the wayside, she says. “There were these contacts where the ER tubes were literally wrapping around the mitochondrial membrane.” When they looked more closely, it appeared that the ER was constricting the mitochondria at some of its contact points.
Most researchers agree that mitochondria divide with the help of a highly conserved cellular protein called dynamin-related protein (Drp1; Dnm1 in yeast), oligomers of ...
