Poly (ADP-Ribose) Polymerase Cleavage Monitored In Situ in Apoptotic Cells. (April 2001)

• Record Type: Journal Article
• Authors: O'Brien, Martha A.; Moravec, Richard A.; Riss, Terry L.
• Is Part Of: Biotechniques. Volume 30:Number 4(2001)
• Page Start: 886
• Page End: 891
• Publication Date: 2001-04
• Subjects: Biology, Experimental -- Periodicals; Molecular biology -- Periodicals; Medical technology -- Periodicals; Biology, Experimental; Medical technology; Molecular biology; Clinical Laboratory Techniques -- Periodicals; Research -- Periodicals; Medical Laboratory Science -- Periodicals; Periodicals; Electronic journals; 570
• DOI: 10.2144/01304pf01
• Languages: English
• ISSNs: 0736-6205

Abstract

During apoptosis, the activation of a family of cysteine proteases, or caspases, results in proteolytic cleavage of numerous substrates. Antibody probes specific for neoepitopes on protein fragments generated by caspase cleavage provide a means to monitor caspase activity at the level of the individual cell. Poly (ADP-ribose) polymerase (PARP), a nuclear enzyme involved in DNA repair, is a well-known substrate for caspase-3 cleavage during apoptosis. Its cleavage is considered to be a hallmark of apoptosis. Here, we demonstrate that an affinity-purified polyclonal antibody to the p85 fragment of PARP is specific for apoptotic cells. Western blots show that the antibody recognizes the 85-kDa (p85) fragment of PARP but not full-length PARP. We demonstrate a time course of PARP cleavage and DNA fragmentation in situ using the PARP p85 fragment antibody and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) in Jurkat cells treated with anti-Fas. Furthermore, our results indicate that the p85 fragment of PARP resulting from caspase cleavage during apoptosis is rapidly localized outside the condensed chromatin but not in the cytoplasm.