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

Telomeres and Telomerase02:41

Telomeres and Telomerase

28.7K
In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded...
28.7K
Telomeres and Telomerase02:41

Telomeres and Telomerase

8.2K
8.2K
Replicative Cell Senescence02:15

Replicative Cell Senescence

4.6K
Replicative cell senescence is a property of cells that allows them to divide a finite number of times throughout the organism's lifespan while preventing excessive proliferation. Replicative senescence is associated with the gradual loss of the telomere — short, repetitive DNA sequences found at the end of the chromosomes. Telomeres are bound by a group of proteins to form a protective cap on the ends of chromosomes. Embryonic stem cells express telomerase — an enzyme that adds...
4.6K
Loss of Tumor Suppressor Gene Functions01:12

Loss of Tumor Suppressor Gene Functions

6.3K
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
6.3K
Loss of Tumor Suppressor Gene Functions01:12

Loss of Tumor Suppressor Gene Functions

2.1K
2.1K
Replication in Eukaryotes01:29

Replication in Eukaryotes

19.2K
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
19.2K

You might also read

Related Articles

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

Sort by
Same author

Toll-like receptor 5 protects against murine lung fibrosis through reduced dysbiosis, and <i>TLR5</i> deficiency is associated with human IPF.

Science translational medicine·2026
Same author

Multilevel impact of cocaine on honeybees: From neurochemistry and mitochondrial dysfunction to superorganism.

Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie·2026
Same author

Paneth cell SIRT1 deficiency increases intestinal stress resistance by modulating the gut microbiota.

EMBO reports·2026
Same author

Self-toxicity and tolerance mechanisms of honeybee venom in honeybees.

The Journal of experimental biology·2026
Same author

A Human Monoclonal Antibody Displays Promiscuous Binding to Multiple Type 1 nsLTP Allergens.

Journal of investigational allergology & clinical immunology·2026
Same author

A Randomized Trial of Drug Route in Out-of-Hospital Cardiac Arrest.

The New England journal of medicine·2024
Same journal

40 years of CENP-A: the foundation of a new era of centromere biology.

Chromosoma·2025
Same journal

Sustainable integrative cell biology: CENP-C is guilty by association.

Chromosoma·2025
Same journal

Molecular and bioinformatics analysis of long non-coding RNAs in cervical cancer.

Chromosoma·2025
Same journal

The synaptonemal complex component corolla regulates meiotic crossover formation in Drosophila melanogaster.

Chromosoma·2025
Same journal

Phosphorylation as a regulatory mechanism of HP1 protein multifunctionality.

Chromosoma·2025
Same journal

A tribute to Chromosoma, Biology of the Nucleus.

Chromosoma·2025
See all related articles

Related Experiment Video

Updated: Apr 7, 2026

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer
08:34

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer

Published on: April 13, 2015

10.8K

Telomerase lost?

James M Mason1, Thomas A Randall2, Radmila Capkova Frydrychova3

  • 1Laboratory of Genome Integrity and Structural Biology, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.

Chromosoma
|July 12, 2015
PubMed
Summary
This summary is machine-generated.

Telomerase is not found in all eukaryotes, suggesting alternative mechanisms like recombination can maintain chromosome ends. A telomere-specific capping complex may be key, not just telomerase.

More Related Videos

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
12:08

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence

Published on: May 22, 2013

47.5K
Telomerase Activity in the Various Regions of Mouse Brain: Non-Radioactive Telomerase Repeat Amplification Protocol TRAP Assay
10:14

Telomerase Activity in the Various Regions of Mouse Brain: Non-Radioactive Telomerase Repeat Amplification Protocol TRAP Assay

Published on: September 2, 2014

15.2K

Related Experiment Videos

Last Updated: Apr 7, 2026

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer
08:34

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer

Published on: April 13, 2015

10.8K
Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
12:08

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence

Published on: May 22, 2013

47.5K
Telomerase Activity in the Various Regions of Mouse Brain: Non-Radioactive Telomerase Repeat Amplification Protocol TRAP Assay
10:14

Telomerase Activity in the Various Regions of Mouse Brain: Non-Radioactive Telomerase Repeat Amplification Protocol TRAP Assay

Published on: September 2, 2014

15.2K

Area of Science:

  • Genetics
  • Molecular Biology
  • Evolutionary Biology

Background:

  • Telomerase and telomeric DNA sequences are common in eukaryotes but not universal.
  • Some species, including certain insects (Diptera, Coleoptera, Hemiptera), lack telomerase or canonical telomeric repeats.
  • The silk moth Bombyx mori has telomeric sequences but lacks functional telomerase.

Purpose of the Study:

  • To investigate the non-universality of telomerase and canonical telomeric sequences across eukaryotes.
  • To explore alternative mechanisms for maintaining chromosome ends in the absence of telomerase.
  • To propose the role of a telomere-specific capping complex in maintaining telomeric sequences.

Main Methods:

  • Comparative genomics and evolutionary analysis to trace telomerase loss.
  • Literature review and analysis of existing data on telomere composition and telomerase presence in various species.
  • Hypothesis formulation based on observed patterns of telomere maintenance.

Main Results:

  • Telomerase was likely lost from Diptera over 260 million years ago.
  • A significant percentage of insect species (Coleoptera, Hemiptera) appear to lack canonical telomeric repeats.
  • The silk moth Bombyx mori presents a case of canonical telomeric sequences without functional telomerase.

Conclusions:

  • Telomerase is not essential for all eukaryotes to maintain chromosome ends.
  • A telomere-specific capping complex may be the primary factor in recognizing and protecting chromosome ends, with telomerase being one mechanism to satisfy this.
  • Alternative end-maintenance pathways, such as recombination, can preserve or evolve telomeric sequences when capping complex specificity is low.