While engaging in cell division research, Silke Hauf and members of her lab made a surprisingly quiet discovery.

A microscope image of fission yeast cells. Individual RNA molecules for two ultra-low noise genes are marked with fluorescence and appear as green and magenta spots. The cell nucleus, where RNA is produced, and the cell outlines are shown in blue. Illustration by Douglas Weidemann and Silke Hauf / Virginia Tech

When cells express RNA, there are always some fluctuations, or noise, in how much RNA is produced. Hauf’s group found several genes whose noise dips below a previously established minimum threshold, known as the noise floor, during expression

“We have solid data for this phenomenon,” said Hauf, associate professor in the Department of Biological Sciences at Virginia Tech. “There are some genes that are different and can have super low noise.”

Often upstaged by the more striking, well-publicized high-noise genes, Hauf and her team were intrigued by these ultra-low noise genes as they provide a window into the understanding of gene expression and gene expression noise.

Members of the Hauf Lab involved in the low-noise gene discovery include (from left) Silke Hauf, Douglas Weidemann, Eric Esposito, and Tatiana Boluarte.

Members of the Hauf Lab involved in the low-noise gene discovery include (from left) Silke Hauf, Douglas Weidemann, Eric Esposito, and Tatiana Boluarte. Photo courtesy of Silke Hauf / Virginia Tech

This discovery, published in the journal Science Advances, includes contributions from co-authors Abhyudai Singh, professor of electrical and computer engineering at the University of Delaware, and Ramon Grima, professor of computational biology at the University of Edinburgh. Both Singh and Grima are also mathematical biologists.

Noise affects cell's function

Hauf said the discovery’s importance lies in helping gain a basic understanding of how these cells do what they do. Cells can’t avoid making noise, but for them to function well, the noise needs to be minimized. She compared it with airports attempting to keep their flights on time in order to gain maximum functionality.

“So it’s exciting to see that there are genes that operate with a minimum level of noise,” said Hauf. “Imagine there was a flight that always left within five minutes of the scheduled departure time. Wouldn’t you want to know how the airline does it?”

DNA double helix - artistic visualization.

DNA double helix – artistic visualization. Image credit: Victoria_Watercolor via Pixabay, free license

Opens the door to more discoveries

Hauf is excited about understanding how these cells express in such a quiet manner and learning more about the mechanisms behind it. According to Douglas Weidemann, team member in the Hauf Lab, “Our discovery shows that there is still a lot to learn about even the basics of how cells regulate RNA levels.” 

“We saw these minimal fluctuations in one particular organism and cell type, but we really need to check other organisms to determine if it is universal,” Hauf said. She also would like to find other genes in this category. 

Source: VirginiaTech