Related Experiment Video
Updated: Aug 6, 2026
11:57
Three-dimensional Super Resolution Microscopy of F-actin Filaments by Interferometric PhotoActivated Localization Microscopy (iPALM)
Published on: December 1, 2016
Spatial Attributes of Actin Filaments Tethered by Myosin Fragments In Vitro Observed Using a Super-Resolution
Daichi Kobayashi1, Taiki Tsujimoto1, Jun-Ichi Hotta2
1Department of Mechanical Systems Engineering, Graduate School of Science and Technology, Yamagata University, Yonezawa, Yamagata, Japan.
Microscopy Research and Technique
|July 22, 2026
Summary
This study demonstrates that a low-cost direct stochastic optical reconstruction microscopy (dSTORM) system can detect nanoscale changes in actin and desmin filaments. The super-resolution imaging reveals size-dependent structural differences and periodic elements within cytoskeletal proteins.
Area of Science:
- Biophysics
- Cell Biology
- Microscopy
Background:
- Cytoskeletal filaments exhibit nanoscale structural dynamics crucial for cellular function.
- Super-resolution microscopy techniques are essential for visualizing these dynamics.
- Direct stochastic optical reconstruction microscopy (dSTORM) offers high spatial resolution.
Purpose of the Study:
- To evaluate the capability of a home-built, low-cost dSTORM system for detecting nanoscale configurational changes in cytoskeletal filaments.
- To visualize actin filaments interacting with myosin fragments and desmin intermediate filaments at super-resolution.
Main Methods:
- Utilized a modified conventional fluorescence microscope with a 532-nm laser to create a dSTORM system.
- Achieved a spatial resolution of 25 nm.
- Imaged AZDye532-labeled actin filaments with myosin fragments and Alexa Fluor 532-labeled desmin filaments in vitro.
Main Results:
- Detected size-dependent configurational differences in actin filaments bound to myosin subfragment-1 (S1) and full-length myosin (FWHM 38 nm vs. 68 nm).
- Visualized desmin intermediate filaments with a transverse FWHM of 65 nm.
- Identified periodic axial intensity peaks in desmin filaments with a spacing of approximately 45 nm.
Conclusions:
- The accessible dSTORM setup effectively detects nanoscale configurational changes in cytoskeletal filaments.
- Super-resolution imaging can reveal structural details and periodic elements within intermediate filaments.
- This approach provides a practical platform for studying protein-protein interactions at the nanoscale.
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