UCPs or uncoupling proteins are present in mitochondria, the powerhouse of each cell in the body. The functions of most of the five known UCPs remain mysterious (UCP2-UCP5), whereby only the distinct function for UCP1 has thus far been discovered. UCP1 is responsible for heat production when muscle activity is deficient such as is the case with babies and animals in hibernation. The research team at the Department of Physiology and Biophysics at the University of Veterinary Medicine in Vienna were able to provide a fundamental explanatory concept for the function of UCP2 and UPC4 for the first time. Each of these proteins are involved in different types of cell metabolism.
UCP2 in Stem Cells and Cancer Cells
In earlier studies of immune cells, lead author, Anne Rupprecht, had already shown that UCP2 could be involved in increased metabolism. Embryonic stem cells precisely exhibit such an increased metabolism, as they rapidly and continually divide, just like cancer cells. Rupprecht searched for various UCPs in embryonic stem cells of mice and in effect found UCP2. "Very high amounts of UCP2 even indicated an especially strong increase in metabolism. In other studies UCP2 had also already been detected in cancer cells", according to Rupprecht.
UCP4 in Nerve Cells
In contrast to UCP2, UCP4 is only found in nerve cells. Nerve cells have a completely different metabolism. They seldom divide, unlike stem cells and cancer cells. The research team of Prof. Elena Pohl therefore examined embryonic stem cells that differentiated to nerve cells in culture. On the basis of this model system, the researchers could show that UCP2 is still existent in the quickly reproducing stem cells, yet at the moment of differentiation are replaced by UPC4.
"In our work, we have examined the natural process of cell differentiation from stem cells to neurons. We know that metabolism changes during differentiation. The fact tha
|Contact: Elena Pohl|
University of Veterinary Medicine -- Vienna