2HD7
Solution structure of C-teminal domain of twinfilin-1.
Summary for 2HD7
| Entry DOI | 10.2210/pdb2hd7/pdb |
| Descriptor | Twinfilin-1 (1 entity in total) |
| Functional Keywords | adf-h, actin binding protein, contractile protein |
| Biological source | Mus musculus (house mouse) |
| Cellular location | Cytoplasm: Q91YR1 |
| Total number of polymer chains | 1 |
| Total formula weight | 16638.95 |
| Authors | Hellman, M.H.,Paavilainen, V.O.,Annila, A.,Lappalainen, P.,Permi, P.I. (deposition date: 2006-06-20, release date: 2007-02-06, Last modification date: 2024-05-29) |
| Primary citation | Paavilainen, V.O.,Hellman, M.,Helfer, E.,Bovellan, M.,Annila, A.,Carlier, M.F.,Permi, P.,Lappalainen, P. Structural basis and evolutionary origin of actin filament capping by twinfilin Proc.Natl.Acad.Sci.Usa, 104:3113-3118, 2007 Cited by PubMed Abstract: Dynamic reorganization of the actin cytoskeleton is essential for motile and morphological processes in all eukaryotic cells. One highly conserved protein that regulates actin dynamics is twinfilin, which both sequesters actin monomers and caps actin filament barbed ends. Twinfilin is composed of two ADF/cofilin-like domains, Twf-N and Twf-C. Here, we reveal by systematic domain-swapping/inactivation analysis that the two functional ADF-H domains of twinfilin are required for barbed-end capping and that Twf-C plays a critical role in this process. However, these domains are not functionally equivalent. NMR-structure and mutagenesis analyses, together with biochemical and motility assays showed that Twf-C, in addition to its binding to G-actin, interacts with the sides of actin filaments like ADF/cofilins, whereas Twf-N binds only G-actin. Our results indicate that during filament barbed-end capping, Twf-N interacts with the terminal actin subunit, whereas Twf-C binds between two adjacent subunits at the side of the filament. Thus, the domain requirement for actin filament capping by twinfilin is remarkably similar to that of gelsolin family proteins, suggesting the existence of a general barbed-end capping mechanism. Furthermore, we demonstrate that a synthetic protein consisting of duplicated ADF/cofilin domains caps actin filament barbed ends, providing evidence that the barbed-end capping activity of twinfilin arose through a duplication of an ancient ADF/cofilin-like domain. PubMed: 17360616DOI: 10.1073/pnas.0608725104 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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