Why do cells destroy their power sources?

By Casey Frye, CCNN Writer

mitochondria diagram
Mitochondria are able to extract energy from the food we eat!

Inside every one of our cells are mitochondria, a kind of organelle (tiny specialized structure) that extracts energy from food to fuel our bodies. They basically provide all the power a cell needs to work properly, which is why they’re known as “power plants.”

However, there are times when these organelles signal a cell, saying “destroy me!” and researchers from the University of Pittsburgh have finally discovered how!

Why would the cell want to destroy mitochondria, though? Well, sometimes they malfunction, and if they continue doing their job, they’ll damage the cell they are inside of and those around it. Think about it. Can you imagine how much damage a city power plant can cause if it lost control? Not only would it hurt itself, it’d also be a threat to the individuals that live near the plant!

The same thing can occur with mitochondria; they can not only harm themselves, but also the rest of the body. In fact, dysfunctional mitochondria can lead to diseases like Parkinson’s Disease (PD), which leaves victims unable to control their muscles. There is no cure for PD, however, so researchers from the University of Pittsburgh hope their discovery might assist in finding one!

Apparently, dysfunctional mitochondria send a signal to cells to let them know they aren’t working properly. As the researchers describe it, the process is similar to cooking a turkey. When in the oven, the poultry seems golden brown and ready to devour. However, a true cook will use a meat thermometer for a clean signal that screams, “Eat me!”

Well, malfunctioning mitochondria release special proteins called LC3s that kind of do the same thing. When the cells detect these proteins, it knows the organelles are ready to be digested and ultimately destroyed. “It’s a survival process,” said Valerian Kagan, Ph.D., a senior author on the paper. Cells activate to get rid of bad mitochondria and consolidate good mitochondria. If this process succeeds, then the good ones can proliferate and the cells thrive.” Basically the bad ones die and the good ones live.

The researchers plan to use this information to discover a cure for PD, which is caused by malfunctions in the powerhouse of the cell. However, there is still a ton of work that needs to be done!

Featured image courtesy of Kelvinsong on Wikimedia. Mitochondria diagram courtesy of BruceBlaus on Wikimedia.