Related Experiment Video
Updated: Jan 11, 2026
12:20
Preparation of Segmented Microtubules to Study Motions Driven by the Disassembling Microtubule Ends
Published on: March 15, 2014
14.9K
MCAK recognizes the nucleotide-dependent feature at growing microtubule ends
Wei Chen1, Yin-Long Song1, Jian-Feng He1
1IDG/McGovern Institute for Brain Research, State Key Laboratory of Complex, Severe, and Rare Diseases, School of Life Sciences, Tsinghua University, Beijing, China.
Elife
|November 19, 2025
Summary
Mitotic centromere-associated kinesin (MCAK) binds to specific nucleotide states at microtubule growing ends. This binding preference reveals how MCAK regulates microtubule dynamics and catastrophe frequency.
Area of Science:
- Cell Biology
- Molecular Biology
- Biophysics
Background:
- Microtubule dynamics are crucial for cell division and motility.
- Mitotic centromere-associated kinesin (MCAK) regulates microtubule depolymerization.
- Understanding MCAK's specific binding to microtubule ends is key to its function.
Purpose of the Study:
- To investigate the end-binding kinetics and specificity of MCAK.
- To elucidate the molecular mechanisms by which MCAK recognizes microtubule ends.
- To differentiate the roles of MCAK and XMAP215 in microtubule regulation.
Main Methods:
- Single-molecule imaging to measure MCAK end-binding kinetics.
- Utilizing GTPγS microtubules to mimic specific nucleotide states.
- Investigating nucleotide-dependent binding of MCAK.
Main Results:
- MCAK binds to both distal and proximal regions of the microtubule GTP cap.
- MCAK exhibits strong binding to GTPγS microtubules, indicating nucleotide-state dependence.
- MCAK and XMAP215 bind to overlapping regions but function independently.
Conclusions:
- MCAK recognizes nucleotide-dependent features of microtubule ends.
- MCAK influences microtubule catastrophe frequency, while XMAP215 affects growth rate.
- New insights into MCAK's regulation of microtubule dynamics at growing ends.
Related Concept Videos
01:32Assembly of Complex Microtubule Structures
2.4K
Complex microtubule structures are present in resting cells and in dividing cells. In resting cells, they are responsible for maintaining the cellular architecture, tracks for intracellular transport, positioning of organelles, assembly of cilia and flagella. They mediate the bipolar spindle assembly for chromosomal segregation and positioning of the cell division plate in dividing cells. The formation of microtubule complex structures depends on the cell type, cell stage, and cell function.
2.4K
01:18Microtubules
10.1K
Microtubules are the thickest cytoskeletal filaments with a diameter of 25 nm. In prokaryotic organisms, microtubules are commonly found in locomotory appendages like cilia and flagella. In eukaryotic cells, microtubules form specialized extensions for moving fluid over the surface, like those found in cells lining the intestine.
Microtubules have two structurally similar globular protein subunits: α and β tubulins. In the cytosol, the α and β tubulins form a heterodimer....
Microtubules have two structurally similar globular protein subunits: α and β tubulins. In the cytosol, the α and β tubulins form a heterodimer....
10.1K
01:35Microtubules
97.9K
There are three types of cytoskeletal structures in eukaryotic cells—microfilaments, intermediate filaments, and microtubules. With a diameter of about 25 nm, microtubules are the thickest of these fibers. Microtubules carry out a variety of functions that include cell structure and support, transport of organelles, cell motility (movement), and the separation of chromosomes during cell division.
97.9K
01:23Microtubule Formation
7.4K
Microtubules are dynamic structures that undergo continuous assembly and disassembly. They originate from specialized multi-protein complexes known as microtubule organizing centers or MTOCs. Within the MTOC, the point of origin of the microtubule is known as the minus end, while the end radiating outward is the plus end. Microtubules serve two primary functions — the organization of spindle complexes to separate sister chromatids during mitotic or meiotic cell division and the formation...
7.4K
01:39Anaphase A and B
5.3K
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...
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
5.3K
01:42Microtubule Associated Proteins (MAPs)
5.7K
Microtubule function and architecture are regulated by an array of specialized proteins called microtubule-associated proteins or MAPs. These proteins are widespread across different organisms and have conserved protein motifs, like the multi-TOG domain for tubulin binding found in the CLASP family of MAPs. Some MAPs are lineage-specific based on their conserved domains. Their functions depend upon the cytoskeletal architecture and cell type they are located within. In-plant cells, a specific...
5.7K