Related Experiment Video
Updated: Jun 4, 2025
08:06
Identification of Kinesin-1 Cargos Using Fluorescence Microscopy
Published on: February 14, 2016
7.9K
KIF1C activates and extends dynein movement through the FHF cargo adapter
Ferdos Abid Ali1,2, Alexander J Zwetsloot3, Caroline E Stone1,4
1MRC Laboratory of Molecular Biology, Cambridge, UK.
Nature Structural & Molecular Biology
|January 2, 2025
Summary
Kinesin-3 KIF1C activates and enhances dynein motor protein function. This discovery explains the codependency of cellular cargo transport motors, revealing a mutual activation mechanism via a shared adapter protein.
Area of Science:
- Cell Biology
- Molecular Motors
- Protein Interactions
Background:
- Cellular cargos move bidirectionally on microtubules using dynein and kinesin motors.
- These motors exhibit codependence, where the activity of one relies on the other, but the underlying mechanism remains unclear.
Purpose of the Study:
- To elucidate the mechanism behind the codependency of dynein and kinesin motors.
- To investigate the role of kinesin-3 KIF1C in regulating dynein activity.
Main Methods:
- In vitro reconstitution assays using purified human proteins.
- Structural modeling of protein complexes.
Main Results:
- Kinesin-3 KIF1C acts as both an activator and a processivity factor for dynein.
- KIF1C activation of dynein is mediated by its nonmotor stalk binding to the cargo adapter HOOK3.
- A structural model explains how KIF1C relieves the autoinhibition of the FTS-HOOK3-FHIP1B complex.
Conclusions:
- The codependency of dynein and kinesin is explained by mutual activation through a shared adapter protein.
- This mechanism, involving KIF1C and HOOK3, likely applies to other bidirectional cellular transport complexes.
Related Concept Videos
01:43The Movement of Organelles and Vesicles
4.4K
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,...
4.4K
01:32Microtubule Associated Motor Proteins
7.7K
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...
7.7K
01:39Anaphase A and B
4.0K
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...
4.0K
01:39Mechanism of Filopodia Formation
2.3K
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
2.3K
01:35Disassembly of Intermediate Filaments
2.0K
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...
2.0K
01:12Adaptability of Cytoskeletal Filaments
3.7K
The cytoskeleton is a complex dynamic structure performing varied functions based on cellular requirements. The adaptability of the individual filaments in the cytoskeleton determines their ability to perform various functions within the cell. It can undergo rapid reorganization during processes like cell division or remain stable for several hours as in the interphase. The adaptability of these filaments depends on stringent regulatory mechanisms. The microfilament and microtubules of the...
3.7K