Unconventional Myosins in Motile and Contractile Functions: Fifty Years on the Stage

Book excerpt: Myosins, actin-dependent molecular motors, are best known for their involvement in muscle contraction. However, besides classical (conventional) myosins, there is a vast number of other myosin motors that structurally and functionally do not resemble muscle myosins and therefore are termed as unconventional myosins. Since discovery in 1973 of the first unconventional myosin, myosin I, in Acanthamoeba castellanii by Thomas D. Pollard and Edward D. Korn, it has been shown that unconventional myosins form a large family, members of which are involved in a plethora of cellular functions, including those associated with intracellular trafficking and cell migration. However, despite the intensive research still many questions persist about their specific role(s) in these processes.