Tuesday, September 22, 2020

'Firefly' method makes cellular forces visible at molecular scale

The image on the left shows the force activity of a cell at a resolution of about 250 nanometers. The image on the right shows how much clearer the image becomes with the resolution of 25 nanometers that is now possible with the new technique. (Microscopy photos by Alisina Bazrafshan)

Scientists have developed a new technique using tools made of luminescent DNA, lit up like fireflies, to visualize the mechanical forces of cells at the molecular level. Nature Methods published the work, led by chemists at Emory University, who demonstrated their technique on human blood platelets in laboratory experiments.

"Normally, an optical microscope cannot produce images that resolve objects smaller than the length of a light wave, which is about 500 nanometers," says Khalid Salaita, Emory professor of chemistry and senior author of the study. "We found a way to leverage recent advances in optical imaging along with our molecular DNA sensors to capture forces at 25 nanometers. That resolution is akin to being on the moon and seeing the ripples caused by raindrops hitting the surface of a lake on Earth."

Almost every biological process involves a mechanical component, from cell division to blood clotting to an immune response. "Understanding how cells apply forces and sense forces may help in the development of new therapies for many different disorders," says Salaita, whose lab is a leader in devising ways to image and map bio-mechanical forces.

The first authors of the paper, Joshua Brockman and Hanquan Su, did the work as Emory graduate students in the lab. Both recently received their PhDs.

Read the full story here.

Related:

New methods reveal the biomechanics of blood clotting

T-cells use 'handshakes' to sort friends from foes

DNA origami takes flight in emerging field of nano machines


No comments:

Post a Comment