Prohibitin,also known as PHB,a member of the Band-7 family of proteins,is widely distributed in bacteria,plants,yeast,protozoa and mammals and is important in cell proliferation,differentiation and apoptosis . This protein localizes to the inner membrane of mitochondria,where it acts as a chaperone protein,and is also found in the nucleus,where it negatively regulates transcription . Recent study confirmed that the expression and distribution of PHB,which is a nuclear matrix protein,affect the apoptosis of HaCaT cells and its co-localization with specific gene products connected with cell apoptosis .