Tropomyosin isoforms differentially tune actin filament length and disassembly
| Autor: | Bruce L. Goode, Silvia Jansen |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Gene isoform
Coronin Tropomyosin macromolecular substances Protein filament Mice 03 medical and health sciences 0302 clinical medicine Microscopy Animals Humans Protein Isoforms Molecular Biology Cytoskeleton Actin 030304 developmental biology 0303 health sciences Total internal reflection fluorescence microscope biology Articles Cell Biology Cofilin Cell biology Actin Cytoskeleton Actin Depolymerizing Factors biology.protein 030217 neurology & neurosurgery Protein Binding |
| Zdroj: | Molecular Biology of the Cell |
| ISSN: | 1939-4586 1059-1524 |
| Popis: | Cellular actin networks exhibit diverse filamentous architectures and turnover dynamics, but how these differences are specified remains poorly understood. Here, we used multicolor total internal reflection fluorescence microscopy to ask how decoration of actin filaments by five biologically prominent Tropomyosin (TPM) isoforms influences disassembly induced by Cofilin alone, or by the collaborative effects of Cofilin, Coronin, and AIP1 (CCA). TPM decoration restricted Cofilin binding to pointed ends, while not interfering with Coronin binding to filament sides. Different isoforms of TPM provided variable levels of protection against disassembly, with the strongest protection by Tpm3.1 and the weakest by Tpm1.6. In biomimetic assays in which filaments were simultaneously assembled by formins and disassembled by CCA, these TPM isoform–specific effects persisted, giving rise to filaments with different lengths and treadmilling behavior. Together, our data reveal that TPM isoforms have quantitatively distinct abilities to tune actin filament length and turnover. |
| Databáze: | OpenAIRE |
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