Tropomyosins as discriminators of myosin function.
Vertebrate nonmuscle cells express multiple tropomyosin isoforms that are sorted to subcellular compartments that have distinct morphological and dynamic properties. The creation of these compartments has a role in controlling cell morphology, cell migration and polarization of cellular components. There is increasing evidence that nonmuscle myosins are regulated by tropomyosin in these compartments via the regulation of actin attachment, ATPase kinetics, or by stabilization of cytoskeletal tracks for myosin-based transport. In this chapter, I review the literature describing the regulation of various myosins by tropomyosins and consider the mechanisms for this regulation.
Ostap
E Michael
EM
Department of Physiology, University of Pennsylvania School of Medicine, B400 Richards Building, Philadelphia, PA 19104-6085, USA. ostap@mail.med.upenn.edu
D000199:Actins / Q000737:chemistry; D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D002384:Catalysis; D003599:Cytoskeleton / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D009124:Muscle Proteins / Q000378:metabolism; D009218:Myosins / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D020033:Protein Isoforms; D014335:Tropomyosin / Q000737:chemistry / Q000502:physiology*
D000199:Actins; D009124:Muscle Proteins; D020033:Protein Isoforms; D014335:Tropomyosin; D000251:Adenosine Triphosphatases; D009218:Myosins