RNA ties itself in knots, then unties itself in mesmerizing video - Livescience.com

Jan 18, 2021

Striking new videos show how RNA — the genetic molecule that tells cells how to build proteins — tangles up in insane knots as it forms, only to disentangle itself at the last second, and in a way that took scientists by surprise. .

Once fully assembled, the RNA assumes its final shape, which dictates how it can interact with other molecules and proteins in the cell. .

"So the RNA has to get out of it," said study author Julius Lucks, an associate professor of chemical and biological engineering and a member of the Center for Synthetic Biology at Northwestern University.

The RNA won't function correctly if it remains trapped in the wrong knot, meaning a knot that gets in the way of its final shape, he said.

To zoom in on how cells build this RNA, the team used chemicals to pause the construction process.

These snapshots served as individual frames in what would become their final videos of RNA formation.

SNP RNA is meant to form in a signature "hairpin-like" shape, and these traps seem to get in the way.

In the videos, the nucleotides highlighted in dark purple knot themselves up, and the dark pink nucleotides help free them, Lucks noted

Learning how RNA tangles and untangles is key to understanding how cells function and how proteins form; the research can also help address diseases where RNA doesn't function properly or a specific protein can't form, such as spinal muscular atrophy, and infectious diseases such as COVID-19 that are caused by RNA viruses, according to a statement. 

It's possible that some proteins act as so-called "RNA chaperones" and help sculpt the molecule into its final form, Lucks said