InterPro domain: IPR002710

The myosin superfamily consists of at least 15 distinct classes of presumedactin-based molecular motors. All members of the superfamily share a similarmotor domain and a tail portion which is diagnostic of the class [ 1 ].

Class V myosins are actin-based molecular motors that function in relativelylong-range movements of many intracellular cargoes including organelles,membrane vesicles, and mRNA [ 2 ]. These motors are ubiquitously found in alleukaryotes. Class V myosins are characterised by the presence of a conservedglobular domain at the C terminus of the tail portion: the dilute domain [ 3 ]. Myosin V moves via attachment of its amino terminal head (motor) domain to actin cables; its carboxyl terminal dilute domain anchors it to cargoes via attachments to organelle-specific receptors [ 4 , 4 ].

The dilute domain is also found in the afadin family. Afadins are nectin andactin filament-binding proteins that connect nectin to the actin cytoskeleton[ 5 ]. The dilute domain of afadin appears to be responsible for actin stress fibre formation [ 6 ].

1. Tails of unconventional myosins. Cell. Mol. Life Sci. 56, 243-57
2. Two distinct regions in a yeast myosin-V tail domain are required for the movement of different cargoes. J. Cell Biol. 150, 513-26
3. AF-6/cno: neither a kinesin nor a myosin, but a bit of both. Trends Biochem. Sci. 20, 265-6
4. Myosin V attachment to cargo requires the tight association of two functional subdomains. J. Cell Biol. 168, 359-64
5. Nectin and afadin: novel organizers of intercellular junctions. J. Cell. Sci. 116, 17-27
6. Afadin regulates RhoA/Rho-associated protein kinase signaling to control formation of actin stress fibers in kidney podocytes. Cytoskeleton (Hoboken) 72, 146-56