Related Experiment Video

Updated: Jul 18, 2026

Induction and Validation of Cellular Senescence in Primary Human Cells
08:18

Induction and Validation of Cellular Senescence in Primary Human Cells

Published on: June 20, 2018

Modulation of replicative senescence of diploid human cells by nuclear ERK signaling

Maria Tresini1, Antonello Lorenzini, Claudio Torres

  • 1Lankenau Institute for Medical Research, Wynnewood, Pennsylvania 19096, USA. tresini@netscape.net

The Journal of Biological Chemistry
|December 6, 2006
PubMed

Insights

Replicative senescence, a key aging process, is regulated by nuclear ERK activity. Inhibiting ERK activity via MKP2 accelerates senescence, while maintaining ERK activity extends cell lifespan.

Area of Science:

  • Cellular biology
  • Molecular biology
  • Aging research

Background:

  • Normal somatic cells have a finite replicative lifespan, leading to senescence.
  • Senescent cells are growth-arrested and exhibit diminished responses to mitogens.
  • ERK signaling pathway activation is crucial for cell proliferation and involves nuclear ERK relocalization, which is impaired in senescent cells.

Purpose of the Study:

  • To investigate the role of nuclear ERK activity in regulating replicative lifespan.
  • To determine the impact of MKP2 (mitogen-activated protein kinase phosphatase 2) on cellular senescence.
  • To explore strategies for extending cellular replicative lifespan by modulating ERK activity.

Main Methods:

  • Manipulating MKP2 expression using ectopic expression and short hairpin RNA (shRNA) for knockdown.
  • Expressing a phosphatase-resistant ERK2 mutant (ERK2(D319N)) to maintain nuclear ERK activity.
  • Assessing cellular senescence, replicative lifespan, and molecular markers like c-fos and Rb.

Main Results:

  • Ectopic expression of MKP2 induced premature senescence.
  • MKP2 knockdown or expression of ERK2(D319N) postponed senescence and extended replicative lifespan.
  • Nuclear targeting of ERK2(D319N) significantly increased lifespan by over 60%.
  • Long-lived cells exhibited altered molecular characteristics, including sustained c-fos expression and inactive Rb.

Conclusions:

  • MKP2-mediated inactivation of nuclear ERK2 is a critical event in establishing replicative senescence.
  • Restoring nuclear ERK activity can bypass senescence checkpoints and extend cellular replicative lifespan.
  • Modulating nuclear ERK activity offers a potential therapeutic target for age-related conditions.

More Related Videos

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols12:02

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols

Published on: June 6, 2017

Techniques to Induce and Quantify Cellular Senescence06:51

Techniques to Induce and Quantify Cellular Senescence

Published on: May 1, 2017

Related Concept Videos

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...
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...
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
Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
DNA Damage Can Stall the Cell Cycle02:36

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...