scholarly journals The role of cytochrome c in caspase activation in Drosophila melanogaster cells

2002 ◽  
Vol 156 (6) ◽  
pp. 1089-1098 ◽  
Author(s):  
Loretta Dorstyn ◽  
Stuart Read ◽  
Dimitrios Cakouros ◽  
Jun R. Huh ◽  
Bruce A. Hay ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Mammalian Cells ◽  
Significant Proportion ◽  
Ectopic Expression ◽  
Caspase Activation ◽  
Cytochrome C Release ◽  
Cell Extracts ◽  
Effector Caspase ◽  
Drosophila Cells

The release of cytochrome c from mitochondria is necessary for the formation of the Apaf-1 apoptosome and subsequent activation of caspase-9 in mammalian cells. However, the role of cytochrome c in caspase activation in Drosophila cells is not well understood. We demonstrate here that cytochrome c remains associated with mitochondria during apoptosis of Drosophila cells and that the initiator caspase DRONC and effector caspase DRICE are activated after various death stimuli without any significant release of cytochrome c in the cytosol. Ectopic expression of the proapoptotic Bcl-2 protein, DEBCL, also fails to show any cytochrome c release from mitochondria. A significant proportion of cellular DRONC and DRICE appears to localize near mitochondria, suggesting that an apoptosome may form in the vicinity of mitochondria in the absence of cytochrome c release. In vitro, DRONC was recruited to a >700-kD complex, similar to the mammalian apoptosome in cell extracts supplemented with cytochrome c and dATP. These results suggest that caspase activation in insects follows a more primitive mechanism that may be the precursor to the caspase activation pathways in mammals.

scholarly journals The two cytochrome c species, DC3 and DC4, are not required for caspase activation and apoptosis in Drosophila cells

2004 ◽  
Vol 167 (3) ◽  
pp. 405-410 ◽  
Author(s):  
Loretta Dorstyn ◽  
Kathryn Mills ◽  
Yuri Lazebnik ◽  
Sharad Kumar
Keyword(s):  
Cytochrome C ◽  
Ectopic Expression ◽  
Human Cells ◽  
Loss Of Function ◽  
Caspase Activation ◽  
Drosophila Cell ◽  
Drosophila Development ◽  
Cell Lysates ◽  
C Proteins ◽  
Drosophila Cells

In Drosophila, activation of the apical caspase DRONC requires the apoptotic protease-activating factor homologue, DARK. However, unlike caspase activation in mammals, DRONC activation is not accompanied by the release of cytochrome c from mitochondria. Drosophila encodes two cytochrome c proteins, Cytc-p (DC4) the predominantly expressed species, and Cytc-d (DC3), which is implicated in caspase activation during spermatogenesis. Here, we report that silencing expression of either or both DC3 and DC4 had no effect on apoptosis or activation of DRONC and DRICE in Drosophila cells. We find that loss of function mutations in dc3 and dc4, do not affect caspase activation during Drosophila development and that ectopic expression of DC3 or DC4 in Drosophila cells does not induce caspase activation. In cell-free studies, recombinant DC3 or DC4 failed to activate caspases in Drosophila cell lysates, but remarkably induced caspase activation in extracts from human cells. Overall, our results argue that DARK-mediated DRONC activation occurs independently of cytochrome c.

scholarly journals Critical function of endogenous XIAP in regulating caspase activation during sympathetic neuronal apoptosis

2003 ◽  
Vol 163 (4) ◽  
pp. 789-799 ◽  
Author(s):  
Patrick Ryan Potts ◽  
Shweta Singh ◽  
Malia Knezek ◽  
Craig B. Thompson ◽  
Mohanish Deshmukh
Keyword(s):  
Cytochrome C ◽  
Mammalian Cells ◽  
Sympathetic Neurons ◽  
Caspase Activation ◽  
Cytochrome C Release ◽  
Critical Function ◽  
Apoptosis Protein ◽  
Induced Apoptosis ◽  
Necessary And Sufficient ◽  
Cytosolic Cytochrome

In sympathetic neurons, unlike most nonneuronal cells, growth factor withdrawal–induced apoptosis requires the development of competence in addition to cytochrome c release to activate caspases. Thus, although most nonneuronal cells die rapidly with cytosolic cytochrome c alone, sympathetic neurons are remarkably resistant unless they develop competence. We have identified endogenous X-linked inhibitor of apoptosis protein (XIAP) as the essential postcytochrome c regulator of caspase activation in these neurons. In contrast to wild-type neurons that are resistant to injection of cytochrome c, XIAP-deficient neurons died rapidly with cytosolic cytochrome c alone. Surprisingly, the release of endogenous Smac was not sufficient to overcome the XIAP resistance in sympathetic neurons. In contrast, the neuronal competence pathway permitted cytochrome c to activate caspases by inducing a marked reduction in XIAP levels in these neurons. Thus, the removal of XIAP inhibition appears both necessary and sufficient for cytochrome c to activate caspases in sympathetic neurons. These data identify a critical function of endogenous XIAP in regulating apoptosis in mammalian cells.

scholarly journals Possible Role of Peroxynitrite in the Responses Induced by Fusicoccin in Plant Cultured Cells

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 182 ◽  
Author(s):  
Massimo Malerba ◽  
Raffaella Cerana
Keyword(s):  
Cytochrome C ◽  
Dna Fragmentation ◽  
Stress Responses ◽  
Molecular Chaperones ◽  
Caspase 3 ◽  
Cultured Cells ◽  
Acer Pseudoplatanus ◽  
Cytochrome C Release ◽  
Induced Stress

Fusicoccin (FC) is a well-known phytotoxin able to induce in Acer pseudoplatanus L. (sycamore) cultured cells, a set of responses similar to those induced by stress conditions. In this work, the possible involvement of peroxynitrite (ONOO−) in FC-induced stress responses was studied measuring both in the presence and in the absence of 2,6,8-trihydroxypurine (urate), a specific ONOO− scavenger: (1) cell death; (2) specific DNA fragmentation; (3) lipid peroxidation; (4) production of RNS and ROS; (5) activity of caspase-3-like proteases; and (6) release of cytochrome c from mitochondria, variations in the levels of molecular chaperones Hsp90 in the mitochondria and Hsp70 BiP in the endoplasmic reticulum (ER), and of regulatory 14-3-3 proteins in the cytosol. The obtained results indicate a role for ONOO− in the FC-induced responses. In particular, ONOO− seems involved in a PCD form showing apoptotic features such as specific DNA fragmentation, caspase-3-like protease activity, and cytochrome c release from mitochondria.

scholarly journals Role of hypoxia-induced Bax translocation and cytochrome c release in reoxygenation injury

Oncogene ◽  
1998 ◽  
Vol 17 (26) ◽  
pp. 3401-3415 ◽  
Author(s):  
Pothana Saikumar ◽  
Zheng Dong ◽  
Yogi Patel ◽  
Kristi Hall ◽  
Ulrich Hopfer ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Release ◽  
Reoxygenation Injury

scholarly journals GAPDH and Autophagy Preserve Survival after Apoptotic Cytochrome c Release in the Absence of Caspase Activation

Cell ◽  
2007 ◽  
Vol 130 (2) ◽  
pp. 385
Author(s):  
Anna Colell ◽  
Jean-Ehrland Ricci ◽  
Stephen Tait ◽  
Sandra Milasta ◽  
Ulrich Maurer ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Caspase Activation ◽  
Cytochrome C Release

scholarly journals Mouse mammary gland involution is associated with cytochrome c release and caspase activation

2001 ◽  
Vol 104 (1-2) ◽  
pp. 89-98 ◽  
Author(s):  
Andreas Marti ◽  
Philipp M. Ritter ◽  
Richard Jäger ◽  
Hedvika Lazar ◽  
Anna Baltzer ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Cytochrome C ◽  
Mouse Mammary Gland ◽  
Caspase Activation ◽  
Cytochrome C Release ◽  
Mammary Gland Involution

Resistance of leukemic cells to 2-chlorodeoxyadenosine is due to a lack of calcium-dependent cytochrome c release

Blood ◽  
2002 ◽  
Vol 99 (2) ◽  
pp. 655-663 ◽  
Author(s):  
Joya Chandra ◽  
Emma Mansson ◽  
Vladimir Gogvadze ◽  
Scott H. Kaufmann ◽  
Freidoun Albertioni ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Dna Fragmentation ◽  
Cell Lines ◽  
Resistant Cell ◽  
Leukemic Cells ◽  
Caspase Activation ◽  
Cytochrome C Release ◽  
Deoxyguanosine Kinase ◽  
Induced Apoptosis ◽  
Resistant Cells

Abstract The purine nucleoside 2-chlorodeoxyadenosine (CdA) is often used in leukemia therapy. Its efficacy, however, is compromised by the emergence of resistant cells. In the present study, 3 CdA-resistant cell lines were generated and characterized. Their ability to accumulate 2-chloroadenosine triphosphate (CdATP) varied, reflecting differences in activities of deoxycytidine kinase (dCK) and deoxyguanosine kinase (dGK). Nonetheless, the selected lines were uniformly resistant to CdA-induced apoptosis, as assessed by caspase activation and DNA fragmentation. In contrast, cytosols from resistant cells were capable of robust caspase activation when incubated in the presence of cytochrome c and dATP. Moreover, replacement of dATP with CdATP also resulted in caspase activation in the parental and some of the resistant cell lines. Strikingly, CdA-induced decreases in mitochondrial transmembrane potential and release of cytochrome c from mitochondria were observed in the parental cells but not in any resistant lines. The lack of cytochrome c release correlated with an increased ability of mitochondria from resistant cells to sequester free Ca2+. Consistent with this enhanced Ca2+buffering capacity, an early increase in cytosolic Ca2+after CdA treatment of parental cells but not resistant cells was detected. Furthermore, CdA-resistant cells were selectively cross-resistant to thapsigargin but not to staurosporine- or Fas-induced apoptosis. In addition, CdA-induced caspase-3 activation and DNA fragmentation were inhibited by the Ca2+ chelator BAPTA-AM in sensitive cells. Taken together, the data indicate that the mechanism of resistance to CdA may be dictated by changes in Ca2+-sensitive mitochondrial events.

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