Yeast as a Model for Human Disease

Kevin A. Morano, Ph.D., assistant professor, microbiology and molecular genetics,
Medical School and Graduate School of Biomedical Sciences (GSBS)

Kevin A. Morano, Ph.D.

You and that sandwich you had for lunch may have more in common than you think. Some species of yeast have long been domesticated for wine, beer and bread making, and yeast is a popular research model because it has remarkably similar biochemical processes to those of humans.

For example, the stress response is similar in the cells of your body and in baker’s yeast, the model that Kevin A. Morano, Ph.D., uses.

“I became interested in this line of research because I wanted to address important issues in human health while taking advantage of the long history of molecular and cellular biology advances in microbial systems such as viruses, bacteria and simple eukaryotes, such as yeast,” Morano said. Yeast provides a cell system in which he can study how the stress response works.

“All cells respond to cytotoxic changes in their environment by activating a stress response,” Morano said.

Understanding the cytotoxic stress response has important implications for human disease. “Pathophysiological conditions like heart disease, tumorigenesis and aging all contribute to stress at the cellular level,” Morano said. Thus, understanding the mechanism of cellular changes underlying such pathologies can help researchers design ways to combat or prevent them.

So how does this stress response work? “The cytotoxic stress response results in the synthesis of a wide variety of protective proteins, most notably the molecular chaperones,” Morano said. Chaperone proteins oversee production, transport and repair of proteins important to proper cell function. Like chaperones at a high school dance, they ensure that everything runs safely and without incident.

In response to stress, chaperones are upregulated to correct the cellular disruption. “Chaperones can refold denatured or otherwise damaged proteins after severe stress,” Morano said.

His new grant focuses on a relatively poorly understood group of chaperone proteins called the Hsp110 family (heat shock protein). “We are studying the yeast version of that chaperone to learn what it does and how it works within the cell,” Morano said. “Work we do in yeast can go a long way toward informing human biology and disease.”