Related Experiment Video
Updated: Feb 28, 2026
04:39
Measuring Axonal Cargo Transport in Mouse Primary Cortical Cultured Neurons
Published on: February 24, 2023
604
Cytoplasmic Dynein Transports Axonal Microtubules in a Polarity-Sorting Manner
Anand N Rao1, Ankita Patil1, Mark M Black2
1Department of Neurobiology and Anatomy, Drexel University, Philadelphia, PA 19129, USA.
Cell Reports
|June 15, 2017
Summary
A motor-based mechanism involving cytoplasmic dynein sorts axonal microtubules, establishing a plus-end-out pattern. Inhibiting dynein disrupts transport and causes minus-end-out microtubules to accumulate.
Area of Science:
- Cell Biology
- Neuroscience
- Biophysics
Background:
- Axonal microtubules exhibit a predominant plus-end-out polarity.
- Understanding the mechanisms governing this organization is crucial for neuronal function.
Purpose of the Study:
- To investigate a motor-based mechanism for axonal microtubule polarity sorting.
- To determine the role of cytoplasmic dynein in this process.
Main Methods:
- Experimental inhibition of cytoplasmic dynein in axons.
- Computational modeling of microtubule transport dynamics.
- Assessment of microtubule polarity and transport following TRIM46 depletion.
Main Results:
- Acute inhibition of cytoplasmic dynein disrupted bi-directional microtubule transport.
- Minus-end-out microtubules accumulated in the axon upon dynein inhibition.
- Computational models indicated dynein, kinesin, and cross-linkers are necessary for polarity maintenance.
- TRIM46 depletion altered microtubule transport, consistent with model predictions.
Conclusions:
- Cytoplasmic dynein plays a critical role in axonal microtubule polarity sorting.
- A combination of motor proteins and cross-linking factors establishes and maintains the plus-end-out microtubule organization.
- This motor-based mechanism is essential for proper axonal microtubule organization.
Related Concept Videos
01:32Microtubule Associated Motor Proteins
11.1K
Eukaryotic cells have different motor proteins for transporting various cargo within the cell. These motor proteins differ based on the filament they associate with, the direction they move within the cell, and the type of cargo they transport. Motor proteins that associate with microtubules are known as microtubule-associated motor proteins. There are two families of microtubule-associated motor proteins —Kinesins and Dyneins. Both these proteins assist in the transport of cellular...
11.1K
01:43The Movement of Organelles and Vesicles
6.8K
In eukaryotic cells, cytoskeletal filaments such as actin, microtubules, and intermediate filaments form a mesh-like cytoskeletal network. These filaments serve as tracks for transporting cellular cargo. Specialized motor proteins use the chemical energy stored in adenosine triphosphate (ATP) for this transport. During interphase, microtubules are polarized, with the plus-end towards the cell periphery and the minus-end towards the cell center. Two microtubule-associated motor proteins,...
6.8K
01:39Anaphase A and B
5.6K
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...
5.6K
01:18Polarity of the Cytoskeleton
25.4K
The intrinsic polarity of cells can be primarily attributed to two factors- i) the asymmetric accumulation of mobile components such are regulatory molecules and subcellular components across the cell and ii) the orientation of polar cytoskeletal filaments that make up the cytoskeletal networks, specifically microfilaments, and microtubules arranged along the axis of polarity. Interactions between the cytoskeletal filaments are crucial for the establishment and maintenance of the polar nature...
25.4K
01:24Microtubules in Cell Motility
4.9K
Microtubules are thick hollow cylindrical proteins that help form the cytoskeleton. Microtubules have varied roles in the cell. These filaments help form cellular appendages like cilia and flagella, which are responsible for locomotion. The cilia arise from basal bodies, separated from the main body by a membrane-like structure forming the transition zone. This zone is the gate for the entry of lipids and proteins, creating a unique composition of lipids and proteins in the ciliary membrane and...
4.9K
01:05Mechanism of Ciliary Motion
5.4K
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
5.4K