Research team developing a nano-sized force sensor and improving high-precision microscopy technology

An international team of researchers has developed a novel microscopic force sensor to study the mechanics of cells. This sensor, measuring about 0.00002 mm, is crafted using components like spider web protein, fluorescent proteins from jellyfish, and alpaca antibodies. It can detect forces within the cell, such as the stretching of the nuclear membrane, a feat previously unachievable.

The sensor's design was inspired during a conference dinner in 2019. It functions like a color-changing rubber band attached to antibodies, which bind to the target protein in a cell. By observing the rubber band's stretch (color change), scientists can determine the force or elongation of the studied protein. This tool, only about twenty nanometres in size, can be applied to various cell biology research areas. It has garnered interest from labs in countries like Japan, India, Norway, and the US.

Understanding the internal forces of cells can shed light on cancer mechanics. As cancer cells grow and move, they experience mechanical forces, which can sometimes benefit cancer development. This new sensor offers a fresh perspective on monitoring these mechanics.

The research was published in the Nature Communications journal. An accompanying image illustrates the sensor's principle, highlighting the jellyfish-derived fluorescent proteins, the spider web protein rubber band, and the alpaca-derived antibodies.

Another study focused on refining expansion microscopy, a super-resolution technique. This method involves enlarging a sample, like a cell, to view its minute details. However, the smaller the cell details, the less visible the molecules become, leading to a "noisy" image. The research team found that repeatedly fluorescently labeling the cells could enhance the image's resolution and contrast. This improved method allows for the detailed study of tiny structures, such as the 120-nanometre Herpes virus, which was previously seen as mere dots with traditional microscopy.

This study was published in the Molecular Biology of the Cell journal. Both studies aim to understand fundamental cell functions, with funding from the Research Council of Finland and support from the Tampere Institute for Advanced Study (IAS).