Thursday 16 October 2003
Intracellular organelle transport is essential for morphogenesis and functioning of the cell.
Kinesins and kinesin-related proteins make up a large superfamily of molecular motors that transport cargoes such as vesicles, organelles (e.g. mitochondria, peroxisomes, lysosomes), protein complexes (e.g. elements of the cytoskeleton, virus particles), and mRNAs in a microtubule- and ATP-dependent manner in neuronal and non-neuronal cells. In 2003, more than 45 kinesin superfamily proteins (KIFs) have been identified in the mouse and human genomes.
Bidirectional microtubule-dependent organelle transport in melanophores is regulated by cAMP through organelle-bound protein kinase A (PKA).
In addition to PKA, transport is regulated by the organelle-bound mitogen-activated protein kinase (MAPKs) signaling components ERK and MEK, whose activity is required for bidirectional transport along microtubules. This pathway apparently acts downstream of PKA, suggesting that bidirectional organelle transport is regulated by a hierarchical cascade of signaling pathways.
Kashina A, Rodionov V. Intracellular organelle transport: few motors, many signals. Trends Cell Biol. 2005 Aug;15(8):396-8. PMID: #16005630#
Fehrenbacher KL, Boldogh IR, Pon LA. Taking the A-train: actin-based force generators and organelle targeting. Trends Cell Biol. 2003 Sep;13(9):472-7. PMID: #12946626#