Kineziny

Kineziny are a class of motor proteins found in eukaryotic cells. They belong to the kinesin superfamily, which also includes kinesin-1 and other related families. Kinesins are essential for intracellular transport, moving various cargo, such as organelles, vesicles, and macromolecules, along microtubule tracks within the cell. This movement is crucial for maintaining cellular structure and function, enabling processes like cell division, cell motility, and signaling.

The primary mechanism of kinesin action involves a "hand-over-hand" walking motion along the microtubule. Kinesin molecules typically possess two motor domains, each capable of binding to ATP and to the microtubule. ATP hydrolysis drives conformational changes that allow the motor domains to move sequentially along the microtubule, effectively "walking" the kinesin and its attached cargo towards the microtubule plus end. This directionality is a key characteristic of many kinesin family members.

Different kinesin subfamilies have evolved to perform specialized roles. For example, some kinesins are involved in transporting specific types of cargo, while others are involved in organizing microtubules or mediating their depolymerization. The precise cargo and destination are often determined by adapter proteins that link the kinesin motor to the cargo. Defects in kinesin function have been implicated in various neurological disorders and other diseases, highlighting their critical importance in cellular health. The study of kinesins continues to provide insights into the fundamental mechanisms of intracellular transport.