<prompt> In apoptosis, cytochrome C acts through -Apaf 1Bcl-2FADDTNF  <response>: Ans. is a i.e., Apaf 1o One of these proteins is cytochrome c, well known for its role in mitochondrial respiration. In the cytosol, cytochrome C binds to a protein called Apaf-1 apoptosis activating factor-1, and the complex activates caspase-9. Bc1-2 and Bcl-x may also directly inhibit Apaf-1 activation, and their loss from cells may permit activation of Apaf-1. 