Apoptotic DNA degradation into oligonucleosomal fragments, but not apoptotic nuclear morphology, relies on a cytosolic pool of DFF40/CAD endonuclease.

ABSTRACT: Apoptotic cell death is characterized by nuclear fragmentation and oligonucleosomal DNA degradation, mediated by the caspase-dependent specific activation of DFF40/CAD endonuclease. Here, we describe how, upon apoptotic stimuli, SK-N-AS human neuroblastoma-derived cells show apoptotic nuclear morphology without displaying concomitant internucleosomal DNA fragmentation. Cytotoxicity afforded after staurosporine treatment is comparable with that obtained in SH-SY5Y cells, which exhibit a complete apoptotic phenotype. SK-N-AS cell death is a caspase-dependent process that can be impaired by the pan-caspase inhibitor q-VD-OPh. The endogenous inhibitor of DFF40/CAD, ICAD, is correctly processed, and dff40/cad cDNA sequence does not reveal mutations altering its amino acid composition. Biochemic

SUBMITTER: Iglesias-Guimarais V 

PROVIDER: S-EPMC3293563 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature