Journal article
Tropomodulins and tropomyosins: working as a team
Journal of muscle research and cell motility, Vol.34(3), pp.247-260
08/2013
Handle:
https://hdl.handle.net/2376/101804
PMCID: PMC4774520
PMID: 23828180
Abstract
Actin filaments are major components of the cytoskeleton in eukaryotic cells and are involved in vital cellular functions such as cell motility and muscle contraction. Tmod and TM are crucial constituents of the actin filament network, making their presence indispensable in living cells. Tropomyosin (TM) is an alpha-helical, coiled coil protein that covers the grooves of actin filaments and stabilizes them. Actin filament length is optimized by tropomodulin (Tmod), which caps the slow growing (pointed end) of thin filaments to inhibit polymerization or depolymerization. Tmod consists of two structurally distinct regions: the N-terminal and the C-terminal domains. The N-terminal domain contains two TM-binding sites and one TM-dependent actin-binding site, whereas the C-terminal domain contains a TM-independent actin-binding site. Tmod binds to two TM molecules and at least one actin molecule during capping. The interaction of Tmod with TM is a key regulatory factor for actin filament organization. The binding efficacy of Tmod to TM is isoform-dependent. The affinities of Tmod/TM binding influence the proper localization and capping efficiency of Tmod at the pointed end of actin filaments in cells. Here we describe how a small difference in the sequence of the TM-binding sites of Tmod may result in dramatic change in localization of Tmod in muscle cells or morphology of non-muscle cells. We also suggest most promising directions to study and elucidate the role of Tmod–TM interaction in formation and maintenance of sarcomeric and cytoskeletal structure.
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Details
- Title
- Tropomodulins and tropomyosins: working as a team
- Creators
- Mert Colpan - The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University 118 Dana Hall, Spokane St. Pullman WA 99164 USANatalia Moroz - The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University 118 Dana Hall, Spokane St. Pullman WA 99164 USAAlla Kostyukova - The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University 118 Dana Hall, Spokane St. Pullman WA 99164 USA
- Contributors
- Steven B Marston (Editor)Mathias Gautel (Editor)
- Publication Details
- Journal of muscle research and cell motility, Vol.34(3), pp.247-260
- Academic Unit
- Chemical Engineering and Bioengineering, School of
- Publisher
- Springer Netherlands; Dordrecht
- Identifiers
- 99900546511601842
- Language
- English
- Resource Type
- Journal article