Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

6.4K
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...
6.4K
Apoptosis01:30

Apoptosis

11.2K
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...
11.2K
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

6.3K
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...
6.3K
Overview of Cell Death01:30

Overview of Cell Death

7.1K
Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the...
7.1K
Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

3.7K
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...
3.7K
Interactions Between Signaling Pathways01:19

Interactions Between Signaling Pathways

6.2K
Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
6.2K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Multifaceted conserved functions of Notch during post-embryonic neurogenesis in the annelid Platynereis.

EMBO reports·2026
Same author

A genome resource for the marine annelid Platynereis spp.

BMC genomics·2025
Same author

The Hydractinia cell atlas reveals cellular and molecular principles of cnidarian coloniality.

Nature communications·2025
Same author

A positive feedback loop between germ cells and gonads induces and maintains sexual reproduction in a cnidarian.

Science advances·2025
Same author

Correction: Animal regeneration in the era of transcriptomics.

Cellular and molecular life sciences : CMLS·2024
Same author

The Rich Evolutionary History of the Reactive Oxygen Species Metabolic Arsenal Shapes Its Mechanistic Plasticity at the Onset of Metazoan Regeneration.

Molecular biology and evolution·2024

Related Experiment Video

Updated: Jun 12, 2025

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

8.6K

Evolution of Apoptotic Signaling Pathways Within Lophotrochozoans.

Helen R Horkan1, Nikolay Popgeorgiev2,3, Michel Vervoort4

  • 1Centre for Chromosome Biology, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland.

Genome Biology and Evolution
|September 25, 2024
PubMed
Summary

Apoptosis pathways show surprising diversity across animals. This study reveals unique evolutionary histories of cell death regulators in lophotrochozoans, highlighting distinct mechanisms in metazoan evolution.

Keywords:
BCL-2 familyapoptosiscaspasesevolutionlophotrochozoansphylogeny

More Related Videos

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis
08:59

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Published on: August 18, 2013

13.5K
Author Spotlight: THP-1 Macrophage Response to LPS/ATP — Unveiling the Pyroptosis, Apoptosis, and Necroptosis Spectrum
06:12

Author Spotlight: THP-1 Macrophage Response to LPS/ATP — Unveiling the Pyroptosis, Apoptosis, and Necroptosis Spectrum

Published on: May 3, 2024

1.7K

Related Experiment Videos

Last Updated: Jun 12, 2025

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

8.6K
Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis
08:59

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Published on: August 18, 2013

13.5K
Author Spotlight: THP-1 Macrophage Response to LPS/ATP — Unveiling the Pyroptosis, Apoptosis, and Necroptosis Spectrum
06:12

Author Spotlight: THP-1 Macrophage Response to LPS/ATP — Unveiling the Pyroptosis, Apoptosis, and Necroptosis Spectrum

Published on: May 3, 2024

1.7K

Area of Science:

  • Evolutionary biology
  • Cell biology
  • Molecular biology

Background:

  • Apoptosis, a crucial form of programmed cell death, is well-understood in model organisms like nematodes, flies, and mammals.
  • However, recent findings indicate divergence in intrinsic apoptosis, and extrinsic apoptosis pathways remain poorly characterized in non-mammalian species.
  • The evolutionary trajectory of apoptotic signaling pathways across metazoans is largely unclear, necessitating research in under-explored biological systems.

Purpose of the Study:

  • To investigate the evolutionary history of key apoptosis regulators, including initiator caspases, caspase activators, and the BCL-2 family, within the Lophotrochozoa.
  • To elucidate the mechanisms and evolution of apoptosis in Lophotrochozoans, a major metazoan clade with significant biodiversity and phylogenetic importance.
  • To address the 'black box' in our understanding of apoptotic signaling pathway evolution by examining a diverse group of invertebrates.

Main Methods:

  • Phylogenetic analysis of initiator caspases, caspase activators, and BCL-2 family proteins in lophotrochozoan genomes.
  • Protein interaction predictions to infer functional relationships and pathway components.
  • Comparative genomics and evolutionary analyses across different lophotrochozoan phyla (molluscs, annelids, brachiopods, platyhelminths).

Main Results:

  • Discovery of significant diversification in initiator caspases within molluscs, annelids, and brachiopods.
  • Identification of the loss of essential extrinsic apoptosis components in platyhelminths.
  • Characterization of a novel, clade-specific caspase with an ankyrin pro-domain in certain lophotrochozoan groups.

Conclusions:

  • Apoptotic actors exhibit a unique evolutionary history within Lophotrochozoa, distinct from previously studied metazoan clades.
  • The findings demonstrate the emergence of specialized apoptotic signaling pathways during metazoan evolution.
  • This study underscores the importance of exploring diverse animal groups to fully comprehend the evolution of fundamental biological processes like cell death.