Related Experiment Video

Updated: Feb 15, 2026

Assaying the Kinase Activity of LRRK2 in vitro
06:09

Assaying the Kinase Activity of LRRK2 in vitro

Published on: January 18, 2012

23.0K

Mms19 is a mitotic gene that permits Cdk7 to be fully active as a Cdk-activating kinase

Rishita Narendra Nag1, Selina Niggli1, Sofia Sousa-Guimarães1

  • 1Institute of Cell Biology, Department of Biology, University of Bern, 3012 Bern, Switzerland.

Development (Cambridge, England)
|January 24, 2018
PubMed

Insights

Mms19 is crucial for cell division and proliferation. It functions in mitosis by regulating the Cdk-activating kinase (CAK) complex, ensuring proper cell cycle progression.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Mms19 is known as a cytosolic iron-sulfur assembly component.
  • Mms19 plays a critical role in cell proliferation and maintaining genomic stability.

Purpose of the Study:

  • To investigate the function of Drosophila Mms19 in mitotic divisions.
  • To elucidate the mechanism by which Mms19 regulates cell cycle progression.

Main Methods:

  • Genetic analysis in Drosophila melanogaster.
  • Investigation of protein interactions using physical and genetic studies.
  • Analysis of mitotic defects, spindle dynamics, and chromosome segregation.

Main Results:

  • Reduced Mms19 activity leads to severe mitotic defects, including impaired spindle dynamics and chromosome segregation.
  • Loss of Mms19 prevents imaginal disc formation, highlighting its role in tissue development.
  • Overexpression of the Cdk-activating kinase (CAK) complex rescues the mitotic defects in Mms19 mutants.
  • Mms19 interacts with Xpd, preventing Xpd binding to CAK and thereby freeing CAK to activate Cdk1.

Conclusions:

  • Mms19 is essential for mitotic progression and cell proliferation in Drosophila.
  • Mms19 regulates Cdk1 activation by modulating the CAK complex through interaction with Xpd.
  • This mechanism is vital for ensuring accurate chromosome segregation and tissue development.
Keywords:
Cdk-activating kinaseDrosophila developmentMitotic geneMms19Xpd

More Related Videos

Assaying Protein Kinase Activity with Radiolabeled ATP08:05

Assaying Protein Kinase Activity with Radiolabeled ATP

Published on: May 26, 2017

19.4K
Monitoring Kinase and Phosphatase Activities Through the Cell Cycle by Ratiometric FRET13:38

Monitoring Kinase and Phosphatase Activities Through the Cell Cycle by Ratiometric FRET

Published on: January 27, 2012

14.7K

Related Concept Videos

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...
6.0K
Co-activators and Co-repressors02:04

Co-activators and Co-repressors

Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
8.7K
Protein Kinases and Phosphatases02:54

Protein Kinases and Phosphatases

Proteins undergo chemical modifications that trigger changes in the charge, structure, and conformation of the proteins. Phosphorylation, acetylation, glycosylation, nitrosylation, ubiquitination, lipidation, methylation, and proteolysis are various protein modifications that regulate protein activity. Such modifications are usually enzyme-driven.
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
15.2K
Eukaryotic Transcription Activators02:42

Eukaryotic Transcription Activators

Transcription activators are proteins that promote the transcription of genes from DNA to RNA. In most cases, these proteins contain two separate domains ‒ a domain that binds to DNA and a domain for activating transcription; however, in some cases, a single domain is responsible for both binding and activation of transcription, as seen in the glucocorticoid receptor and MyoD.
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These...
12.9K
tRNA Activation02:26

tRNA Activation

Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
23.2K
Activation Energy01:26

Activation Energy

Activation energy is the minimum amount of energy necessary for a chemical reaction to move forward. The higher the activation energy, the slower the rate of the reaction. However, adding heat to the reaction will increase the rate, since it causes molecules to move faster and increase the likelihood that molecules will collide. The collision and breaking of bonds represents the uphill phase of a reaction and generates the transition state. The transition state is an unstable high-energy state...
87.2K