Related Experiment Video

Updated: May 10, 2026

Purification of Ubiquitinated p53 Proteins from Mammalian Cells
10:55

Purification of Ubiquitinated p53 Proteins from Mammalian Cells

Published on: March 21, 2022

ARF regulates the stability of p16 protein via REGγ-dependent proteasome degradation

Takashi Kobayashi1, Jingqiang Wang, Hikmat Al-Ahmadie

  • 1Columbia University Medical Center, 1130 St. Nicholas Ave., New York, NY 10031, USA.

Molecular Cancer Research : MCR
|July 3, 2013
PubMed
Abstract

Insights

The cell-cycle regulator p14-ARF (ARF) controls the stability of the related protein p16. ARF promotes p16 degradation via the proteasome and REGγ, impacting tumor suppressor pathways.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Cell Biology

Background:

  • The CDKN2A gene encodes two tumor suppressors, p14ARF and p16INK4a, with distinct functions.
  • Their complementary roles in regulating p53 and pRB pathways suggest coordinated control.
  • The precise regulatory mechanisms between p14ARF and p16INK4a remain incompletely understood.

Purpose of the Study:

  • To investigate the regulatory relationship between p14ARF and p16INK4a.
  • To elucidate the mechanism by which p14ARF influences p16INK4a stability.
  • To identify key molecular players involved in this interaction.

Main Methods:

  • Experiments were conducted in human cancer cell lines and mouse embryonic fibroblasts (MEFs).
  • Protein stability assays were used to assess p16INK4a degradation.
  • Proteasome activity and REGγ interaction were investigated.
  • Knockdown of REGγ and pharmacologic inhibition of nuclear export were employed.

Main Results:

  • p14ARF (ARF) was found to regulate the stability of p16INK4a protein.
  • ARF promotes the rapid, proteasome-mediated degradation of p16INK4a.
  • This degradation is dependent on the interaction of ARF with the proteasome subunit REGγ.
  • Blocking REGγ nuclear export or its knockdown abrogates ARF-induced p16INK4a destabilization.

Conclusions:

  • A novel crosstalk mechanism between the tumor suppressors p14ARF and p16INK4a has been uncovered.
  • This interaction is mediated by a REGγ-dependent pathway, influencing p16INK4a protein stability.
  • The ability of ARF to control p16INK4a stability may have significant implications for cell-cycle regulation and cancer progression.

More Related Videos

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence04:56

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence

Published on: December 30, 2025

Related Concept Videos

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.
Covalently Linked Protein Regulators02:04

Covalently Linked Protein Regulators

Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
Regulated Protein Degradation02:58

Regulated Protein Degradation

It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Regulated Protein Degradation02:58

Regulated Protein Degradation

It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Regulation of Expression at Multiple Steps01:23

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...