Related Experiment Video

Updated: Jun 4, 2026

Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex
07:17

Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex

Published on: August 2, 2021

Caspase-8 and bid: caught in the act between death receptors and mitochondria

Chahrazade Kantari1, Henning Walczak

  • 1Tumour Immunology Unit, Division of Immunology and inflammation, Department of Medicine, Imperial College London, Hammersmith Hospital Campus, Commonwealth Building Du Care Road, London, UK.

Biochimica Et Biophysica Acta
|February 8, 2011
PubMed

Insights

Mitochondria mediate cell death through outer membrane permeabilization. Type II cells require this mitochondrial pathway for apoptosis, unlike type I cells, involving caspase-8 and Bid signaling.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Mitochondria are key regulators of both cell survival and cell death.
  • Apoptosis involves outer mitochondrial membrane permeabilization and release of pro-apoptotic factors.
  • Cellular responses to death receptor signaling differ between Type I and Type II cells.

Purpose of the Study:

  • To review the signaling events from death receptor stimulation to mitochondrial outer membrane permeabilization in Type II cells.
  • To highlight recent findings on the regulation and activation of caspase-8 and Bid.
  • To discuss the determinants distinguishing Type I and Type II cells in apoptosis.

Main Methods:

  • Literature review of research on mitochondrial apoptosis.
  • Analysis of signaling pathways involving caspase-8 and Bid.
  • Synthesis of current knowledge on Type I vs. Type II cell apoptosis.

Main Results:

  • Type II cells necessitate mitochondrial pathway activation for apoptosis induction following death receptor stimulation.
  • Caspase-8 and Bid are critical mediators of this mitochondrial signaling.
  • Emerging data reveal complex regulation of caspase-8 and Bid function.

Conclusions:

  • Understanding the mitochondrial pathway in Type II cells is crucial for elucidating apoptosis.
  • Further research is needed to fully understand caspase-8 and Bid regulation and the Type I/Type II cell distinction.
  • Mitochondria play a pivotal, yet complex, role in programmed cell death.

More Related Videos

Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation08:47

Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation

Published on: March 5, 2018

Evaluation of Caspase Activation to Assess Innate Immune Cell Death10:23

Evaluation of Caspase Activation to Assess Innate Immune Cell Death

Published on: January 20, 2023

Related Concept Videos

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...
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...
Caspases01:24

Caspases

Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.
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.
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...
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...