Myosin Motors

    The 'traditional' myosin motors have been studied a great deal, predominantly as the motors used in muscle contraction, moving actin filaments relative to each other (see, for example, the lab of Dr. Justin Molloy at the university of York, England).  However, there are also 'non-traditional' Myosin motors, such as Myosin-V, that move cargos along actin filaments.  Why some cargos are transported using the actin-myosin cytoskeletal system, and some by the Microtubule-kinesin/dynein system is not yet fully determined. In fact, some cargos such as pigment granules in melanophores use both types of motors to carry the cargos along both classes of cytoskeletal filaments. Exactly how common is this use of both cytoskeletal systems? We're not yet sure, but we already know a number of different cargos, so it may be quite general. The interactions between the different cytoskeletal systems, and the  regulation of  the different motors on such cargos, is a topic of active research in my lab and others.

A number of people have contributed greatly to our understanding of myosin function. You may want to start by looking at the work of Dr. Jim Spudich (Stanford) and Dr. Mark Mooseker (Yale). This is NOT even scratching the surface of important work by a large number of people.