Carrier Protein Kinesin
The Kinesin are the molecules that carry protein to nerves, like the amazing network in our brains.
Kinesins were discovered as MT-based anterograde intracellular transport motors. The founding member of this superfamily, kinesin-1, was isolated as a heterotetrameric fast axonal organelle transport motor consisting of 2 identical motor subunits (KHC) and 2 “light chains” (KLC) via microtubule affinity purification from neuronal cell extracts. Subsequently, a different, heterotrimeric plus-end-directed MT-based motor named kinesin-2, consisting of 2 distinct KHC-related motor subunits and an accessory “KAP” subunit, was purified from echinoderm egg/embryo extracts and is best known for its role in transporting protein complexes (IFT particles) along axonemes during cilium biogenesis. Molecular genetic and genomic approaches have led to the recognition that the kinesins form a diverse superfamily of motors that are responsible for multiple intracellular motility events in eukaryotic cells. For example, the genomes of mammals encode more than 40 kinesin proteins, organized into at least 14 families named kinesin-1 through kinesin-14.
These videos are exceptionally well made and explanatory:
- In the first video, the animation is fantastic and the analogy of city commuting well represent the challenges facing the process. ~ 5 min.
- The second is a Ted Talk ~ 10 min
- The third video is a more in-depth explanation by Ron Vale and it is great, but it is ~40 minutes and gets pretty deep. This is for you if you want to learn about the reasons why Kinesin and other carriers travel ‘one-way’ (spoiler; the nucleated centrosomes create polarized microtubials).