Related Experiment Video

Updated: May 6, 2026

Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations
07:14

Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations

Published on: September 20, 2019

7.8K

Disruption of clathrin-mediated trafficking causes centrosome overduplication and senescence

Maciej B Olszewski1, Panagiotis Chandris, Bum-Chan Park

  • 1Laboratory of Cell Biology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.

Traffic (Copenhagen, Denmark)
|October 22, 2013
PubMed

Insights

Inhibiting G cyclin-associated kinase (GAK) causes cells to accumulate multiple centrosomes and become senescent. This occurs due to disrupted intracellular trafficking, DNA damage, and altered cell signaling pathways.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • G cyclin-associated kinase (GAK) is an Hsc70 cochaperone crucial for clathrin chaperoning.
  • Clathrin-dependent trafficking plays a vital role in cellular processes.
  • Understanding the impact of GAK inhibition on cell cycle progression is important.

Purpose of the Study:

  • To investigate the effects of complete inhibition of clathrin-dependent trafficking on the cell cycle.
  • To elucidate the mechanisms underlying the observed cellular phenotypes.
  • To determine the role of GAK in cell cycle regulation and senescence.

Main Methods:

  • Utilized conditional GAK knockout mouse embryonic fibroblasts (MEFs).
  • Analyzed cell cycle progression, centrosome duplication, and senescence.
  • Examined signaling profiles, including Akt phosphorylation.
  • Assessed lysosomal membrane stability and DNA damage.
  • Performed knockdown of clathrin heavy chain, dynamin, and adaptor protein (AP2).

Main Results:

  • GAK knockout led to multiple centrosomes, failed cell division, and senescence.
  • GAK inhibition increased Akt phosphorylation and destabilized lysosomal membranes, causing DNA damage.
  • Disrupting clathrin heavy chain or dynamin largely mimicked the GAK knockout phenotype.
  • Inhibiting only clathrin-mediated endocytosis (AP2 knockdown) caused growth arrest and centrosome overduplication without DNA damage or senescence.

Conclusions:

  • Disruption of clathrin-dependent trafficking induces senescence and centrosome overduplication.
  • A combination of DNA damage and altered mitogenic signaling contributes to this phenotype.
  • Centrosomal duplication becomes uncoupled from DNA replication upon GAK inhibition.
Keywords:
DNA damagecentrosomeclathrinendocytosisoverduplicationsenescencetrafficking

More Related Videos

Quantitative Immunofluorescence Assay to Measure the Variation in Protein Levels at Centrosomes09:39

Quantitative Immunofluorescence Assay to Measure the Variation in Protein Levels at Centrosomes

Published on: December 20, 2014

14.8K
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins05:35

Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins

Published on: March 3, 2016

15.1K

Related Concept Videos

Centrosome Duplication02:25

Centrosome Duplication

The primary microtubule organizing center (MTOC) in animal cells is the centrosome. A centrosome has two cylindrical centrioles at its core. Each centriole consists of nine sets of three microtubules held together by proteins. The centrioles are positioned at right angles to each other and surrounded by a shapeless protein cloud called the pericentriolar matrix, or pericentriolar material (PCM).
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
3.7K
Centrosome Duplication02:25

Centrosome Duplication

2.6K
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...
3.5K
Replicative Cell Senescence02:15

Replicative Cell Senescence

3.0K
Centrioles and Centrosomes01:13

Centrioles and Centrosomes

Most animal cells comprise a pair of centrioles together called a centrosome. The cell duplicates its centrosome and contains two centrosomes side-by-side, which begin to move apart during the prophase. As the centrosomes migrate to two different sides of the cell, microtubules start extending from each centrosome toward the other end. The mitotic spindle is composed of the centrosomes and their emerging microtubules.
Near the end of the prophase, also called late prophase or...
6.9K
Separation of Sister Chromatids02:17

Separation of Sister Chromatids

At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
3.6K