Researchers have discovered a whole new level of stunning details within our live cells by swapping out fluorescent molecules in an existing imaging procedure with ones that instead scatter light.
The novel modification will give researchers a direct window into molecular behavior over a much longer time scale, providing insight into crucial biological processes like cell division.
Biomedical engineer Guangjie Cui of the University of Michigan says, “The live cell is a busy environment with proteins swarming here and there. “To view these dynamic activities, our superresolution is very appealing.”
Using superresolution, it is possible to see minuscule biological details. The blurring impact of a flood of diffracted light is removed by taking a succession of pictures of fluorescing molecule constellations that emphasize specific regions of the targeted tissue.
In 2014, the scientists who worked on it were awarded the Nobel Prize. Despite the process’s groundbreaking nature, mapping longer-lasting processes is impossible because the fluorescing molecules’ capacity to absorb and then spit back the necessary wavelength of light burns out after only a few tens of seconds.
Instead, Cui and colleagues created a system to detect light reflecting off randomly positioned gold nanorods, which doesn’t degrade under repeated exposure to light. The same very precise resolution is achieved by imaging numerous, differently angled subsets of the rods and merging the images, despite the fact that the gold markers are larger than the target structures.
A stunning 250 hours of continuous observations at a resolution of only 100 atoms are possible with the resulting device.
The entire process of cellular division was then investigated by Cui and colleagues using a novel PINE nanoscopy technique, which revealed previously unobserved behavior of actin molecules at the level of the individual molecules.
The main constituent of a cell’s cytoskeleton, actin, gives cells structural support and aids in movement inside a cell. Therefore, these branching filament-shaped molecules have a significant impact on how a cell divides and then separates into two daughter cells.
Because of the limitations of our visual technology, it has been unclear exactly how these cells inherit the same interiors, including proteins and DNA, from their parent cells.
Cui and his team were able to observe the interactions between individual molecules in 904 actin filaments as the cell divides. They discovered that actin molecules stretch to form additional linkages when they are less connected to one another. Each actin reaches its neighbors and draws other actin molecules in, expanding the network.
The scientists observed how these minute changes affected a larger-scale cellular perspective. Unexpectedly, the cell as a whole actually contracts when actin expands, whereas it expands when actin contracts. The researchers are eager to learn how this opposite motion is happening because it seems inconsistent.
Biomedical engineer Somin Lee from the University of Michigan stated in an article for The Conversation that the team plans to apply its technology to investigate how other molecular building blocks assemble into tissues and organs.
Our method may make it easier for researchers to see and, in turn, comprehend how molecular flaws in tissues and organs may lead to disease.
This research was published in Nature Communications.
