Analysis of nuclear apoptotic process in a cell-free system.
We report an analysis of the apoptotic process of mouse liver nuclei induced in a cell-free carrot cytosol system by cytochrome c. Typical characteristics of apoptosis were observed, such as chromatin condensation, margination, apoptotic bodies and DNA ladders. Furthermore, transmission and scanning electron microscope analysis of the apoptotic nuclei detected chromatin-free nuclear vesicles before apoptotic bodies appeared at a comparatively late phase. When AC-YVAD-CHO, an inhibitor of caspase 6, was introduced into the system, these vesicles and apoptotic bodies disappeared completely within our study sections. We confirmed the results using whole-mount electron microscopy, and found that although the nuclear lamina was destroyed early, the nuclear matrix largely remained intact during the course of apoptosis. The nuclear matrix played an important role in maintaining the integrity of apoptotic cells and connecting the apoptotic bodies and apoptotic nucleus.
Zhao
Y
Y
College of Life Sciences, Peking University, Beijing, PR China. zhaizh@plum.lsc.pku.edu.cn
Wu
M
M
Shen
Y
Y
Zhai
Z
Z
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D053178:Caspase 6; D061945:Caspase Inhibitors; D002467:Cell Nucleus / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D002474:Cell-Free System; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D003574:Cytochrome c Group / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D018552:Daucus carota; D066298:In Vitro Techniques; D034882:Lamins; D008099:Liver / Q000166:cytology; D051379:Mice; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009687:Nuclear Proteins / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology
D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D003574:Cytochrome c Group; D034882:Lamins; D009687:Nuclear Proteins; D009842:Oligopeptides; C096429:L 709049; C505516:Casp6 protein, mouse; D053178:Caspase 6