Related Experiment Video

Updated: Aug 30, 2026

LPS and ATP-induced Death of PMA-differentiated THP-1 Macrophages and its Validation
06:12

LPS and ATP-induced Death of PMA-differentiated THP-1 Macrophages and its Validation

Published on: May 3, 2024

Apoptosis: bombarding the mitochondria

Philippe Parone1, Muriel Priault, Dominic James

  • 1Department of Cell Biology, University of Geneva, 30 quai Ansermet, 1211 Geneva 4, Switzerland.

Essays in Biochemistry
|October 31, 2003
PubMed

Insights

Mitochondria are key to programmed cell death (apoptosis) by integrating signals and releasing proteins. They can also trigger apoptosis via reactive oxygen species production.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Mitochondria are central regulators of apoptosis, a crucial process for development and disease.
  • They integrate various death signals and orchestrate the activation of caspases.

Purpose of the Study:

  • To elucidate the mechanisms by which mitochondria control apoptosis.
  • To highlight the role of mitochondrial outer membrane permeabilization and reactive oxygen species.

Main Methods:

  • Analysis of mitochondrial signaling pathways.
  • Investigation of Bcl-2 family protein interactions.
  • Assessment of apoptogenic factor release.
  • Study of reactive oxygen species generation in apoptosis.

Main Results:

  • Mitochondria integrate death signals via Bcl-2 family proteins.
  • Caspase activation is coordinated by the release of intermembrane space proteins.
  • Outer mitochondrial membrane permeabilization is critical for this release.
  • Mitochondria can initiate apoptosis through reactive oxygen species.

Conclusions:

  • Mitochondria are pivotal in initiating and executing apoptosis through multiple pathways.
  • Regulation of outer mitochondrial membrane permeability and reactive oxygen species production are key mitochondrial functions in cell death.

More Related Videos

Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c07:42

Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c

Published on: June 29, 2011

Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis12:55

Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis

Published on: February 16, 2015

Related Concept Videos

Apoptosis01:30

Apoptosis

Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size reduction of the tissue.
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
Autophagic Cell Death01:18

Autophagic Cell Death

Christian de Duve discovered “autophagy,” a process in which cellular components are engulfed by membrane-bound organelles called autophagosomes. The autophagosomes then fuse with lysosomes to digest the enclosed contents. Autophagy is generally activated in cells to prevent cell death. However, cell death is triggered when the damage is beyond repair.
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
Cellular Injury V: Apoptosis and Autophagy01:22

Cellular Injury V: Apoptosis and Autophagy

Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or  immature dendritic cells. Non-professional phagocytes such as  epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes. 
Normal cells contain receptors that prevent them from being recognized by phagocytes.