Related Experiment Video

Updated: May 12, 2026

Caspase-3 Activity in the Rat Amygdala Measured by Spectrofluorometry After Myocardial Infarction
08:41

Caspase-3 Activity in the Rat Amygdala Measured by Spectrofluorometry After Myocardial Infarction

Published on: January 12, 2016

Active caspase-3 is removed from cells by release of caspase-3-enriched vesicles

A N Böing1, J Stap, C M Hau

  • 1Department of Clinical Chemistry, Academic Medical Center, Amsterdam, The Netherlands. A.N.Boing@amc.nl

Biochimica Et Biophysica Acta
|March 28, 2013
PubMed

Insights

Caspase-3 induces membrane blebbing and releases caspase-3 enriched vesicles in breast cancer cells. These vesicles are taken up by other cells without causing apoptosis, suggesting a role in cellular homeostasis.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Caspase-3 cleavage of Rho-associated Coiled Coil Kinase I (ROCK I) is known to cause membrane blebbing.
  • The role of caspase-3 and ROCK I in membrane vesicle release remains unclear.

Purpose of the Study:

  • To investigate the role of caspase-3 in membrane vesicle release.
  • To determine if caspase-3 and ROCK I are involved in the release of membrane vesicles.

Main Methods:

  • Transfection of a caspase-3 deficient human breast cancer cell line (MCF-7) with caspase-3.
  • Analysis of membrane blebbing and membrane vesicle release in transfected cells.
  • Characterization of caspase-3 content and activity in released membrane vesicles.

Main Results:

  • Caspase-3 expression in MCF-7 cells induced ROCK I-mediated membrane blebbing.
  • Small membrane vesicles (400-600nm) were released in a ROCK I-independent manner.
  • These vesicles were enriched in caspase-3 and its activity, and were taken up by untransfected cells without inducing apoptosis.

Conclusions:

  • Membrane vesicle release and membrane blebbing are distinct, differentially regulated processes.
  • Packaging of caspase-3 into vesicles may contribute to cellular homeostasis by removing excess caspase-3.
  • Vesicle release may protect the cellular environment from direct caspase-3 exposure.

More Related Videos

In Vitro Cleavage Assays using Purified Recombinant Drosophila Caspases for Substrate Screening08:16

In Vitro Cleavage Assays using Purified Recombinant Drosophila Caspases for Substrate Screening

Published on: October 6, 2022

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

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.
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...
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.
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...
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.
Regulated Protein Degradation02:58

Regulated Protein Degradation

It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...