Related Experiment Video
Updated: May 10, 2026
07:35
Immobilization of Caenorhabditis elegans to Analyze Intracellular Transport in Neurons
Published on: October 18, 2017
Isolation of intraflagellar transport trains
Caterina Mencarelli1, Aaron Mitchell, Roberto Leoncini
1Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy.
Cytoskeleton (Hoboken, N.J.)
|June 28, 2013
Summary
Researchers isolated intraflagellar transport (IFT) trains, revealing these flexible strings of particles are composed of soluble IFT particles. This finding clarifies the structure of IFT trains, essential for flagellar assembly and function.
Area of Science:
- Cell Biology
- Molecular Biology
- Biophysics
Background:
- Intraflagellar transport (IFT) is crucial for flagellar assembly and function.
- IFT trains, observed in situ, are linear arrays of electron-dense particles.
- IFT trains are believed to dissociate into soluble IFT particles (~16-17S complexes).
Purpose of the Study:
- To isolate and characterize intraflagellar transport (IFT) trains.
- To confirm the structural relationship between soluble IFT particles and IFT trains.
- To provide a foundation for higher-resolution structural studies of IFT trains.
Main Methods:
- Electron microscopy for in situ visualization of IFT trains.
- Sucrose gradient centrifugation to purify soluble IFT particles.
- Immunolabeling to identify polypeptide composition of isolated IFT trains.
Main Results:
- Isolated flexible strings of IFT particles structurally resembling in situ IFT trains.
- Demonstrated that isolated IFT trains are composed of both complex A and complex B polypeptides.
- Confirmed that particles in isolated IFT trains are structurally similar to ~17S gradient peak particles.
Conclusions:
- Provided the first direct evidence that ~17S particles constitute IFT trains.
- Achieved the first successful isolation of IFT trains.
- Opened avenues for advanced structural investigations of IFT train composition and assembly.
Related Concept Videos
01:32Microtubule Associated Motor Proteins
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 cargos...
01:24Microtubules in Cell Motility
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...
01:45Destabilization 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...
01:35Disassembly of Intermediate Filaments
Intermediate filaments (IFs) do not undergo spontaneous disassembly. Enzymes, kinases, and phosphatases add and remove phosphates from specific sites to regulate their disassembly. The IF concentration in the cytoplasm also regulates the disassembly. If the concentration crosses a threshold, it activates the protein kinases in the vicinity, allowing the phosphorylation of IFs.
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
01:45Vesicular Tubular Clusters
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...
01:43The Movement of Organelles and Vesicles
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,...