Brain complexity: protecting mitochondria (Introduction)

by David Turell , Friday, January 15, 2016, 20:18 (3235 days ago) @ David Turell

Cells contain many mitochondria which provide constant energy. the cells have a mechanism to protect mitochondria from damage through an enzyme:-http://www.sciencedaily.com/releases/2016/01/160114152323.htm-"Researchers have known for years that mitochondria undergo this fragmentation when treated with drugs that affect the mitochondria, but the biochemical details of how the mitochondria damage is sensed and how that triggers the rapid fission response has not been clear until now.-"In the new work, the Salk team found that when cells are exposed to mitochondria damage, a central cellular fuel gauge, the enzyme AMPK, sends an emergency alert to mitochondria instructing them to break apart into many tiny mitochondrial fragments.-***-"Prior research by Shaw's group and others had uncovered AMPK's role in helping to recycle damaged mitochondrial pieces as well as signaling to the cell to make new mitochondria. But this new role of rapidly triggering mitochondrial fragmentation "really places AMPK at the heart of mitochondria health and long-term well-being," says Shaw.-***-"The team discovered why this was: when the cell's power stations are disrupted, the amount of energy floating around a cell -- ATP -- is lowered. After just a few minutes, AMPK detects this reduction of energy in the cell and hurries to the mitochondria. Like a guard pulling a fire alarm, AMPK activates a receptor on the outside membrane of a mitochondrion to signal it to fragment.-"Drilling down further, the researchers found that AMPK actually acts on two areas of a mitochondrial receptor, called mitochondrial fission factor (MFF), to start the process. MFF calls over a protein, Drp1, that binds and wraps around the mitochondrion like a beaded noose to twist and break it apart.-"'We discovered that the modification of MFF by AMPK is needed for MFF to call over more Drp1 to the mitochondria," says Erin Quan Toyama, one of the first authors of the paper and a Salk research associate. "Without AMPK sending the alarm, MFF cannot call over to Drp1 and there is no new fragmentation of mitochondria after damage.'"-Comment: Once again an enzyme, which is a large complex molecule, runs the protective reaction. Mitochondria are thought to be bacteria that were engulfed early in evolution ( Lynn Margulies). How did the protective mechanism get added? It is obviously necessary and it is a complex molecule. Further note that the whole protective process is a series of organized molecular reactions following a plan.