University of California San Francisco
Helen Diller Family Comprehensive Cancer Center

Researcher of the Month: Stephen Floor, PhD

By Shelley Wong | Research.UCSF.edu | January 17, 2020

Researcher of the Month: Stephen Floor, PhD

Stephen Floor, PhD, is assistant professor of cell and tissue biology in the School of Dentistry.

If cells are made of molecules that have no agency, how can they make decisions? Stephen Floor, PhD, assistant professor of cell and tissue biology in the School of Dentistry, is interested in the control of gene expression at the level of RNA.

“For many genes, when you turn the gene on and start making RNA, you make protein by default,” says Floor (lab website). “But for some genes, the RNAs that are produced are highly regulated. You can produce an RNA that makes zero protein or you can produce an RNA that makes protein in a context-dependent manner. We’re most interested in this collection of genes that make special messenger RNAs with regulatory information that allows the cell to make decisions in response to the environment and other cues.”

In 2018, Floor was one of six UCSF early-career scientists to receive a National Institutes of Health (NIH) Director’s Award, funded by the High-Risk, High-Reward Research program, part of the NIH Common Fund. One of the major objectives in Floor’s lab is to find a way to use emerging types of RNA sequencing to measure not just the average properties of protein production from mRNA, but how each individual mRNA is producing proteins. There are types of translation or protein synthesis that differ between messenger RNAs on the endoplasmic reticulum and messenger RNAs in the bulk cytoplasm. Developing a sequencing tool capable of such measurement would allow Floor and colleagues to ask questions like whether the percentage of mRNAs producing protein differs depending on their position.

Floor contrasts his background in computer science and physics with the scientific challenges of biology. “You can go back to an analytic theory or a program, and you can diagram and say, ‘If we put these pieces together, it will work like this,’” he says. “Biology is very chaotic. You can write down the best plan that looks beautiful on paper, but because biology is so complex, it’s extremely difficult to actually transition that plan into something that works. And not only is it difficult, it doesn’t always behave in ways that you understand, so taking an idea and realizing that idea is much more difficult in biology than it is in many other systems.”

"It’s a marriage of discovering things about the natural world through computation and analysis of datasets.
Stephen Floor, PhD
Assistant Professor of Cell and Tissue Biology

As an undergraduate computer science major, Floor found his interest shifting from writing video games to science after taking a physics course and learning how essential computers were for scientific experiments.

“It seemed like a really exciting way to use the power of computation and it’s still very central to what we do. All of the sequencing generates huge amounts of data, so my lab right now is about a third computational, two-thirds experimental. It’s a marriage of discovering things about the natural world through computation and analysis of datasets,” says Floor.

Read more at Research.UCSF.edu