Kinesine

Kinesins are a family of motor proteins that move along microtubules, translating ATP hydrolysis into mechanical work to transport cellular cargo. They are involved in intracellular transport, mitosis, and meiosis.

Most kinesins travel toward the microtubule plus end, but a subset move toward the minus end.

Most kinesins are dimers with two motor domains at the N-terminus, a coiled-coil stalk, and a cargo-binding tail. The motor cycle combines ATP binding, neck-linker docking, and ATP hydrolysis to generate 8-nm steps.

Functions include long-range transport of vesicles and organelles, plus organization of spindle microtubules during cell division and neuronal cargo delivery.

Diversity across families (kinesin-1, -2, -3, -5, -13) supports specialized roles. Most move toward plus ends, whereas kinesin-14 and some others move to the minus end.

Regulation occurs through cargo binding, adaptor proteins, phosphorylation, and interactions with microtubule-associated proteins.

In physiology, kinesins support neuronal health and proper cell division; defects can contribute to neurodegenerative and developmental disorders.

Kinesins are widely used in research for single-molecule mechanics and in vitro transport assays.