ABSTRACT
Motor proteins are involved in a large number of biological processes. But their main functions, most probably, are to support different aspects of cellular transport as well as cellular processes that require exerting mechanical forces (Lodish et al. 2007, Alberts et al. 2007, Bray 2001, Howard 2001) [95, 4, 23, 68]. In this book, we already discussed various motor protein systems. Experimental and theoretical studies suggest that many motor proteins are strong enough as single particles to move rapidly and to exert large forces in biological cells. For example, kinesin motor proteins can be viewed as very efficient nanoscale machines that are able to perform individually multiple complex tasks (Howard 2001, Carter and Cross 2005, Clancy et al. 2011) [68, 27, 31]. Although single motor proteins can develop significant forces and run long distances along their tracks, many in vivo and in vitro experimental studies show that biological molecular motors usually work in groups (Ally et al. 2009, Holzbaur and Goldman 2010, Kulic et al. 2008, Soppina et al. 2008, Efremov et al. 2014) [6, 66, 90, 151, 47]. The number of motor proteins in these groups might vary. It is interesting to note that in many cases different types of motor proteins, even antagonistic to each other, might cooperate in performing their tasks.
