Processive 8-nm Kinesin Stepping Resolved with the NanoTracker

^{KEYWORDS: Optical Tweezers; NanoTracker; Fluorescence Microscopy; Optical Integration; Force Measurements; Motor Proteins; Kinesin; Microtubules; Nanomanipulation; Life Science}

The combination of optical tweezers with back-focal-plane detection allows for the simultaneous position and force detection at nm and pN resolution, respectively. The NanoTracker is the first off-the-shelf optical tweezers system to deliver a complete solution providing the capacity of sub-picoNewton force measurements together with high spatial and temporal resolution of the position of the molecule. The instrument furthermore merges versatile methodologies by combining ultra-stable dual trap optical tweezers with DIC imaging and fluorescence visualization.

In this application note, it is demonstrated that the tracking of the processive movement of motor proteins such as kinesin can be easily performed, yielding information on kinetics, step sizes, and forces associated with the movement. With the NanoTracker, Bruker provides another tool to perform ultra-sensitive measurements on the single molecule level for life scientists.

Readers can expect to learn about:

• The configuration and calibration of the NanoTracker Optical Tweezers system for performing motor-protein experiments, showcasing the easy operation and the seamless integration with optical microscopy;
• Experimental assay and detailled discussion of the results showing the outstanding resolution of the system; and
• The exceptional potential of the NanoTracker for single-molecule experiments under native conditions.