Gerald W. Dorn II, MD, the Philip and Sima K. Needleman Professor of Medicine at Washington University said that this study is surprising because biologists always assumed that organ development was orchestrated from the nucleus of a cell, and that the mitochondria simply followed along and did what they were told.
He said that they've shown that mitochondria can direct what type of tissue a cell will become during embryonic development.
Luca Scorrano, MD, PhD, professor of biochemistry at the University of Padua-Dulbecco Telethon Institute in Italy said that using a tissue culture technique he calls "hearts in the tube," they were able to unravel a novel way used by the ancient invader to take control of cell fate.
The researchers were careful to note that the underdeveloped hearts were not simply the result of a lack of fuel from dysfunctional mitochondria. Scorrano's team showed that these fragmented mitochondria, small and separated because they could not fuse together, interrupt well-known signaling pathways that govern how the nucleus expresses genes.
Several of these signaling pathways already are implicated in congenital heart defects, such as those that result in holes in the wall separating the left and right ventricles, called ventricular septal defects.
The study has been published in Science Express.