Related Experiment Video

Updated: Aug 30, 2026

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
12:26

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay

Published on: May 3, 2018

The cyclin-dependent kinase 11(p46) isoform interacts with RanBPM

Monika Mikolajczyk1, Jiaqi Shi, Richard R Vaillancourt

  • 1Department of Pathology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA.

Biochemical and Biophysical Research Communications
|September 27, 2003
PubMed

Insights

We discovered that Ran-binding protein (RanBPM) interacts with cyclin-dependent kinase 11 (CDK11(p46)), a key player in apoptosis. This interaction reveals a new signaling pathway for CDK11(p46) in programmed cell death.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Cyclin-dependent kinase 11 (CDK11) exists as larger isoforms (CDK11(p110)) and a smaller, apoptosis-promoting form (CDK11(p46)) generated during programmed cell death.
  • The precise signaling mechanisms of CDK11(p46) in apoptosis remain largely uncharacterized.

Purpose of the Study:

  • To identify interacting partners of the caspase-processed CDK11(p46).
  • To elucidate the molecular mechanisms underlying CDK11(p46)-mediated apoptosis signaling.

Main Methods:

  • Yeast two-hybrid screening to identify protein-protein interactions.
  • In vitro binding assays and studies in human cells to confirm interactions.
  • Analysis of protein domains, specifically the SPRY domain of RanBPM.
  • In vitro kinase assays to assess phosphorylation activity.

Main Results:

  • Ran-binding protein (RanBPM) was identified as a direct interacting partner of CDK11(p46).
  • The interaction between CDK11(p46) and RanBPM was confirmed both in vitro and within human cells.
  • The SPRY domain of RanBPM is essential for its association with CDK11(p46).
  • CDK11(p46) was demonstrated to phosphorylate RanBPM.

Conclusions:

  • RanBPM is a novel binding partner for the apoptosis-associated kinase CDK11(p46).
  • The interaction is mediated by the SPRY domain of RanBPM, suggesting a structural basis for the complex.
  • CDK11(p46) possesses kinase activity towards RanBPM, indicating a potential regulatory mechanism within the apoptosis pathway.

More Related Videos

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors10:33

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors

Published on: October 26, 2015

Related Concept Videos

Positive Regulator Molecules02:39

Positive Regulator Molecules

Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
Positive Regulator Molecules01:45

Positive Regulator Molecules

To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
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.
Anaphase Promoting Complex00:50

Anaphase Promoting Complex

The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
Directionality of Nuclear Transport01:42

Directionality of Nuclear Transport

Ras-related nuclear protein or Ran is a small G protein that cycles between its GTP and GDP bound states. Ran specific regulators, a Ran GTPase Activating Protein or RanGAP present in the cytosol and a Ran guanine nucleotide exchange factor or RanGEF present inside the nucleus regulate GTP/GDP exchange. A high concentration of GTP inside the cells, in addition to this asymmetric distribution of  Ran-specific regulators, leads to a higher RanGTP concentration inside the nucleus. This...