Gene silencing and mitochondrial signalling

Upon physiological stimulation, mitochondria undergo major rise in mitochondrial [Ca2+], well in the range of the Ca2+ sensitivity of the matrix dehydrogenases, in a wide variety of cells types, ranging from non excitable,e.g. HeLa and CHO, and excitable, e.g. cell lines to primary cultures of various embryological origin, such as myocytes, adipocytes and neurons. This review briefly summarizes a few basic features of mitochonrial Ca2+ handling and its involvement in the mitochondrion of Ca2+-dependent signaling. Afterwards. the role of mitochondrial Ca2+ in the control of apoptotic cell death and during oxidative stress is discussed. Finally, data will be presented on RNA interference techniques to study mitochondrial calcium signalling.