Microscope developed at MBL tracks individual molecules in living cells

October 3, 2016 by Diana Kenney, University of Chicago
New microscope shows the actin filament orientation in human skin cells, corresponding to the color wheel at bottom left. Credit: Shalin Mehta and Tomomi Tani

Scientists at the Marine Biological Laboratory and colleagues have unveiled a new microscope that can track the position and orientation of individual molecules in living cells—nanoscale measurements that until now have posed a significant challenge.

As reported this week in the Proceedings of National Academy of Sciences, the team's "instantaneous fluorescence polarization" microscope offers new insights into how cells achieve directed functions or forces.

"All functions of cells are directed. For example, cells move in a specific direction or divide at a certain site and orientation so the two are the right size. That direction comes from the nanoscale alignment of molecules in the cells, which this microscope can detect," said lead author Shalin Mehta, staff scientist in the University of Chicago's Department of Radiology and a staff researcher at MBL.

Understanding how cellular components work requires peering at a nanoscale—to the activity of billionth-of-a-meter-sized molecules that assemble to form the cell's components and drive their functions.

"With this microscope, we can see the orientation of a single molecule, or an assembly of molecules as they form a higher-order structure," said co-author Tomomi Tani, an MBL associate scientist. The scope can also detect minute conformational changes that are required for the protein's function.

Credit: University of Chicago

Polarized light microscopes, iterations of which been developed at the MBL since the 1950s, exploit "a property of light not visible to the human eye to measure molecular order below the resolution limit of the microscope," Mehta explained.

The team used the microscope to address various biological questions in collaboration with other scientists at the MBL, including Amy Gladfelter of University of North Carolina, Chapel Hill, and Clare Waterman of the National Institutes of Health.

"That is a unique feature of being at the MBL," Mehta said. "We were able to study three biological questions while our method was under development. Trying to solve each question led us to improve the microscope and the algorithms with every iteration."

Explore further: A look at living cells down to individual molecules

More information: Shalin B. Mehta et al. Dissection of molecular assembly dynamics by tracking orientation and position of single molecules in live cells, Proceedings of the National Academy of Sciences (2016). DOI: 10.1073/pnas.1607674113

Related Stories

A look at living cells down to individual molecules

August 3, 2015

EPFL scientists have been able to produce footage of the evolution of living cells at a nanoscale resolution by combining atomic force microscopy and an a super resolution optical imaging system that follows molecules that ...

New imaging method reveals nanoscale details about DNA

June 17, 2016

Researchers have developed a new enhanced DNA imaging technique that can probe the structure of individual DNA strands at the nanoscale. Since DNA is at the root of many disease processes, the technique could help scientists ...

Researchers outsmart the biological uncertainty principle

July 12, 2016

Anyone who has ever taken a group photo will be familiar with the problem: If everyone is constantly running around, it's almost impossible to get a sharp photo. Cell biologists who want to visualize molecular processes inside ...

Recommended for you

EPA adviser is promoting harmful ideas, scientists say

March 22, 2019

The Trump administration's reliance on industry-funded environmental specialists is again coming under fire, this time by researchers who say that Louis Anthony "Tony" Cox Jr., who leads a key Environmental Protection Agency ...

Coffee-based colloids for direct solar absorption

March 22, 2019

Solar energy is one of the most promising resources to help reduce fossil fuel consumption and mitigate greenhouse gas emissions to power a sustainable future. Devices presently in use to convert solar energy into thermal ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.