Intracellular Movement of Peroxisomes (PO) and Lipid Droplets (LD) In mammals and filamentous fungi, POs and LDs are uniformly distributed in cells where they undergo short-range stochastic motility. This uniform distribution and local random motility may lead to frequent organelle-organelle interactions that are known to support their various cellular functions. It was shown that the uniform distribution of PO and LD is the result of cytoskeletal action. Among them, the directional and random movement of PO receives regulation by microtubule, while myosin 5 is responsible for the slow polar drift of PO.
Peroxisomes migrate to the cell tip in the absence of MTs or kinesin-3 .
Cytoskeletal Proteins Regulate Mitochondrial Transport Mitochondria are cellular power plants that provide ATP necessary for neuronal growth, survival, and regeneration. The distribution of mitochondria to distal axons depends on microtubule (MT) based motors that move them in both directions along the axon by mechanisms that require ATP hydrolysis to adapt to the physiological processes of the cell.
Organelle Transport Mediated by Cytoskeletal Protein Modifications
Microtubule is further diversified by many post-translational modifications, such as acetylation of α- and β-microtubule, methylation of α-microtubule, phosphorylation of α- and β-microtubule, etc.
Post-translational modifications of microtubule proteins vary widely between cell types and are developmentally and spatially regulated. Many studies have now documented the selective transport of various cargoes across a subset of microtubules that have undergone specific modifications. For example, as lysosomes move from the cell periphery to the cell interior, they switch between tyrosylated and acetylated microtubules. Vesicles in epithelial cells leave the trans-Golgi network along polyglutamylated microtubules that are functionalized by septin-2 fibers and aligned with the apical basal cell axis. In flagella, cargo movement is efficiently separated for cis- and retrograde transport by moving on adjacent tracks of differentially modified microtubule duplexes.