Related Experiment Video

Updated: Aug 21, 2026

Analyzing Telomeric Protein-DNA Interactions Using Single-Molecule Magnetic Tweezers
11:21

Analyzing Telomeric Protein-DNA Interactions Using Single-Molecule Magnetic Tweezers

Published on: August 30, 2024

Telomere biology: a new player in the end zone

Lorel Colgin1, Roger Reddel

  • 1Cancer Research Unit, Children's Medical Research Institute, 214 Hawkesbury Road, Westmead, Sydney, NSW 2145, Australia.

Current Biology : CB
|October 23, 2004
PubMed

Insights

A newly identified protein, PTOP/PIP1/TINT1, acts as a negative regulator of telomere length. It connects key telomere proteins, increasing the complexity of telomere maintenance.

Area of Science:

  • Genetics
  • Molecular Biology
  • Cell Biology

Background:

  • Telomeres are protective caps at the ends of chromosomes.
  • Telomere length is regulated by a complex set of proteins.
  • Dysregulation of telomere length is associated with aging and cancer.

Purpose of the Study:

  • To identify and characterize novel proteins involved in telomere length regulation.
  • To elucidate the interactions of PTOP/PIP1/TINT1 with known telomere-binding proteins.

Main Methods:

  • Protein interaction studies (e.g., co-immunoprecipitation).
  • Analysis of telomere length in cells with altered PTOP/PIP1/TINT1 expression.

Main Results:

  • Identification of PTOP/PIP1/TINT1 as a novel telomere-associated protein.
  • PTOP/PIP1/TINT1 negatively regulates telomere length.
  • PTOP/PIP1/TINT1 interacts with TRF1, TIN2, POT1, and TRF2.

Conclusions:

  • PTOP/PIP1/TINT1 is a significant addition to the known telomere protein network.
  • This protein adds complexity to the understanding of telomere maintenance mechanisms.

More Related Videos

Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence12:08

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

Published on: May 22, 2013

Modified Terminal Restriction Fragment Analysis for Quantifying Telomere Length Using In-gel Hybridization11:29

Modified Terminal Restriction Fragment Analysis for Quantifying Telomere Length Using In-gel Hybridization

Published on: July 10, 2017

Related Concept Videos

Telomeres and Telomerase02:41

Telomeres and Telomerase

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 DNA.
Telomeres and Telomerase02:41

Telomeres and Telomerase

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 DNA.
Replication in Eukaryotes01:29

Replication in Eukaryotes

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...
Replication in Eukaryotes02:31

Replication in Eukaryotes

Overview
Replicative Cell Senescence02:15

Replicative Cell Senescence

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 the telomeric...
Long-patch Base Excision Repair01:02

Long-patch Base Excision Repair

Since the discovery of the two BER pathways, there has been a debate about how a cell chooses one pathway over the other and the factors determining this selection. Numerous in vitro experiments have pointed out multiple determinants for the sub-pathway selection. These are: