Related Experiment Video

Updated: Mar 19, 2026

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles
07:47

Directly Measuring Forces Within Reconstituted Active Microtubule Bundles

Published on: May 10, 2022

2.0K

DDA3 and Mdp3 modulate Kif2a recruitment onto the mitotic spindle to control minus-end spindle dynamics

Hye Jin Kwon1, Ji Eun Park1, Haiyu Song1

  • 1Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul 140-742, Republic of Korea.

Journal of Cell Science
|June 11, 2016
PubMed

Insights

Mdp3 protein complexes with DDA3 to regulate microtubule (MT) dynamics at the mitotic spindle minus-end. This interaction fine-tunes Kif2a recruitment, ensuring proper chromosome segregation during cell division.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Microtubule (MT) dynamics are crucial for cell division, regulated by depolymerases and plus-end-tracking proteins (+TIPs).
  • Mechanisms controlling MT dynamics at the minus-end, particularly poleward flux, remain incompletely understood.

Purpose of the Study:

  • To investigate the role of Mdp3 (MAP7D3) in regulating spindle MT dynamics at the minus-end.
  • To elucidate the interaction between Mdp3 and DDA3 (PSRC1) in controlling MT dynamics and chromosome segregation.

Main Methods:

  • Depletion of Mdp3 in cells.
  • Analysis of spindle MT stability and dynamics.
  • Assessment of chromosome alignment and segregation.
  • Immunofluorescence microscopy to determine protein localization.

Main Results:

  • Mdp3 forms a complex with DDA3 and inhibits DDA3-mediated Kif2a recruitment to the spindle minus-end.
  • Mdp3 depletion leads to aberrant Kif2a activity, decreased spindle stability, and chromosome segregation errors.
  • DDA3 and Mdp3 do not affect each other's localization despite opposing roles in MT dynamics.

Conclusions:

  • The DDA3-Mdp3 complex orchestrates MT minus-end dynamics by fine-tuning Kif2a recruitment.
  • This regulation is essential for maintaining spindle stability, poleward MT flux, and accurate chromosome segregation during mitosis.
Keywords:
DDA3Kif2aMdp3Microtubule fluxMinus-end spindle dynamics

More Related Videos

Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets10:52

Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets

Published on: August 13, 2016

10.3K
Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis08:33

Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis

Published on: December 5, 2017

15.1K

Related Concept Videos

Anaphase A and B01:39

Anaphase A and B

Microtubules form through the end-to-end polymerization of tubulin heterodimers. Kinetochore microtubules originate from the spindle poles, and their plus-ends connect with the kinetochores on sister-chromatids. Ndc80 protein complexes, present on the kinetochore, form low-affinity links with the plus end of these kinetochore microtubules.
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
5.7K
The Mitotic Spindle02:27

The Mitotic Spindle

The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures...
8.3K
Spindle Assembly02:50

Spindle Assembly

Spindle assembly occurs through three, often coexisting, pathways – the centrosome-mediated pathway, the chromatin-mediated pathway, and the microtubule-mediated pathway – collectively contributing to form a robust spindle apparatus.
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a...
4.4K
Forces Acting on Chromosomes02:11

Forces Acting on Chromosomes

During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis. 
Microtubules and motor proteins exert two types of forces on...
4.1K
Destabilization of Microtubules01:45

Destabilization of Microtubules

The destabilization of microtubules can occur during different stages of the microtubule lifecycle, such as nucleation or elongation. It can take place at either end of the microtubule or in the microtubule lattices as a whole. The lifespan of individual microtubules within a cell varies according to the cell type and stage of the cell cycle. During interphase, the lifespan of the microtubule is about 30 minutes, while during cell division, it is about 15 minutes. In axonal microtubules of...
3.8K
Microtubule Instability02:17

Microtubule Instability

Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated...
6.4K