Calmodulin regulates dimerization, motility, and lipid binding of Leishmania myosin XXI
| Autor: | Constanze Helbig, Christopher Batters, Heike Ellrich, Christian Hundschell, Katy Woodall, Dario Brack, Claudia Veigel |
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| Jazyk: | angličtina |
| Rok vydání: | 2013 |
| Předmět: |
Myosin light-chain kinase
Calmodulin Protein Conformation Movement Oligonucleotides Motility macromolecular substances Myosins Fluorescence Myosin head Protein structure Microscopy Electron Transmission Myosin Fluorescence Resonance Energy Transfer Actin Phospholipids Leishmania Multidisciplinary biology Cell biology Förster resonance energy transfer PNAS Plus Area Under Curve biology.protein Baculoviridae Dimerization Plasmids |
| Popis: | Myosin XXI is the only myosin expressed in Leishmania parasites. Although it is assumed that it performs a variety of motile functions, the motor’s oligomerization states, cargo-binding, and motility are unknown. Here we show that binding of a single calmodulin causes the motor to adopt a monomeric state and to move actin filaments. In the absence of calmodulin, nonmotile dimers that cross-linked actin filaments were formed. Unexpectedly, structural analysis revealed that the dimerization domains include the calmodulin-binding neck region, essential for the generation of force and movement in myosins. Furthermore, monomeric myosin XXI bound to mixed liposomes, whereas the dimers did not. Lipid-binding sections overlapped with the dimerization domains, but also included a phox-homology domain in the converter region. We propose a mechanism of myosin regulation where dimerization, motility, and lipid binding are regulated by calmodulin. Although myosin-XXI dimers might act as nonmotile actin cross-linkers, the calmodulin-binding monomers might transport lipid cargo in the parasite. |
| Databáze: | OpenAIRE |
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