Katsuhiko Murakami, Ph.D.

Research

Gene expression is fundamental to all organisms, and studying how the genetic code is expressed in molecular terms is critical to cell development and understanding diseases. My research interests are centered on understanding the mechanism of gene expression, particularly how information stored in genomic DNA is transcribed into RNA by the enzyme RNA polymerase—the first step and the key control point in the gene expression and one of the most fundamental processes required for life. We apply X-ray crystallography and cryo-electron microscopy techniques to reveal three-dimensional structures of bacterial, archaeal, and bacteriophage RNA polymerases for elucidating the mechanisms of RNA transcription and its regulation.

As an Innovation Fund investigator, Katsuhiko Murakami, Ph.D., is teaming up with Gene-Wei Li, Ph.D., to study a critical step of gene regulation in a distinct group of bacteria known as cyanobacteria. Proper expression of genes is critical for the health of all organisms. One key step in this process is known as transcription termination, meaning the way in which RNA polymerase stops making RNA based on where a gene ends within a DNA sequence. Cyanobacteria play a critical role in everyday life: They are responsible for the majority of carbon fixation on Earth but also cause illness in humans and livestock. Surprisingly, the molecular mechanism by which transcription termination occurs in cyanobacteria is unknown, despite this process being well documented in other model bacteria. The collaboration will combine Murakami’s expertise in structural biology of RNA polymerase with Li’s knowledge of transcriptional regulation to establish a new model for microbial transcriptional termination in cyanobacteria. Their discoveries could have broad-reaching impacts extending to chloroplasts and other bacterial species.