α-Actinin/titin interaction: A dynamic and mechanically stable cluster of bonds in the muscle Z-disk
| Autor: | Kristina Djinović-Carugo, Marco Grison, Ulrich Merkel, Julius Kostan, Matthias Rief |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Repetitive Sequences Amino Acid Sarcomeres Optical Tweezers Recombinant Fusion Proteins Anchoring Nanotechnology Passive stretching macromolecular substances 03 medical and health sciences 0302 clinical medicine Protein Domains Protein Interaction Mapping Cluster (physics) Animals Humans Actinin Connectin Amino Acid Sequence Cysteine Actin Physics Multidisciplinary biology Biological Sciences musculoskeletal system 030104 developmental biology Optical tweezers biology.protein Biophysics Mutagenesis Site-Directed α actinin Cystine Titin Rabbits Stress Mechanical 030217 neurology & neurosurgery |
| Zdroj: | Proceedings of the National Academy of Sciences of the United States of America. 114(5) |
| ISSN: | 1091-6490 |
| Popis: | Stable anchoring of titin within the muscle Z-disk is essential for preserving muscle integrity during passive stretching. One of the main candidates for anchoring titin in the Z-disk is the actin cross-linker α-actinin. The calmodulin-like domain of α-actinin binds to the Z-repeats of titin. However, the mechanical and kinetic properties of this important interaction are still unknown. Here, we use a dual-beam optical tweezers assay to study the mechanics of this interaction at the single-molecule level. A single interaction of α-actinin and titin turns out to be surprisingly weak if force is applied. Depending on the direction of force application, the unbinding forces can more than triple. Our results suggest a model where multiple α-actinin/Z-repeat interactions cooperate to ensure long-term stable titin anchoring while allowing the individual components to exchange dynamically. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|