Tropomyosin pp 283-292 | Cite as

Tropomodulin/Tropomyosin Interactions Regulate Actin Pointed End Dynamics

  • Alla S. Kostyukova
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 644)


Dynamics of the slow-growing (pointed) end of the actin filament is regulated by tropomodulins, a family of capping proteins that require tropomyosin for optimal function. Tropomodulin is an elongated molecule with a molecular mass of about 40 kDa, containing the Tm-independent actin-binding site at the C-terminus. The highly disordered N-terminal half of tropomodulin contains two Tm-binding sites and a Tm-dependent actin-binding site. There are many Tm isoforms whose distribution varies in different tissues and cell compartments and changes during development of these tissues. Tropomyosin/tropomodulin interactions are isoform specific. Differences in Tm affinity for the two binding sites in Tmod may regulate its correct positioning at the pointed end as well as effectiveness of capping actin filament. The regulation of tropomodulin binding may have significant consequences for local cytoskeletal formation and filament dynamics in cells.


Circular Dichroism Coiled Coil Heptad Repeat Fast Skeletal Muscle Endothelial Cell Motility 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Landes Bioscience and Springer Science+Business Media 2008

Authors and Affiliations

  • Alla S. Kostyukova
    • 1
  1. 1.Department of Neuroscience and Cell BiologyRobert Wood Johnson Medical SchoolPiscatawayUSA

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