Jones R A, Johnson V L, Hinton R H, Poirier G G, Chow S C, Kass G E
School of Biological Sciences, University of Surrey, Guildford, Surrey, United Kingdom.
Biochem Biophys Res Commun. 1999 Mar 16;256(2):436-41. doi: 10.1006/bbrc.1999.0313.
In hepatocytes the DNA repair enzyme poly(ADP-ribose)polymerase (PARP) is not proteolytically cleaved during apoptosis. The reason for this was investigated using a cell-free system that consisted of isolated nuclei from hepatocytes or thymocytes and cytosolic extracts from hepatocytes or thymocytes undergoing apoptosis. It was found that liver PARP is resistant to proteolytic cleavage by the caspases present in the cytosolic extracts. Furthermore, liver PARP was not cleaved by recombinant human caspase-3. It is concluded that PARP proteolysis cannot be used as a marker for hepatocyte apoptosis.
