Why I’m a Scientist: Dr. Fang Li
Dr. Fang Li’s study of viral entry has led to discoveries with major implications for some of the world’s most dangerous pathogens.
Dr. Fang Li is a professor of Pharmacology at the University of Minnesota. He is an internationally recognized structural biologist who studies how viruses enter human cells and how this process can be blocked. His path to science, however, did not begin in biology.
The Roots: From Mathematics to Structural Biology
Dr. Li grew up in a family deeply rooted in mathematics: both of his parents were university professors of mathematics, and his grandfather was a mathematics educator. He showed exceptional talent early; in high school, he won first prize in China’s national mathematics competition and later graduated among the country’s very top science students.
“Everybody expected me to become a mathematician,” he recalls. “My family, my friends, my teachers.”
For a time, mathematics seemed like his natural path.
In college, however, he was drawn in a different direction. Biology offered him a way to apply analytical thinking to the complexity of living systems while addressing problems with direct relevance to human health. Over time, this interest led him to structural biology, where computational methods and biology come together. “I enjoy imagining protein structures, much like I enjoyed three-dimensional geometry in high school,” he says.
The Spark: A Scientific Calling in Viruses
His path eventually led him to the structural biology of viruses. Despite their apparent simplicity, viruses are remarkably efficient biological systems; they recognize host receptors, enter cells, and adapt to new environments.
Dr. Li earned his PhD in structural biology at Yale University under the mentorship of Nobel laureate Thomas Steitz. Soon afterward, as he was deciding between research on cancer and viruses, the 2002–2003 SARS outbreak changed the course of his career. “I was deciding between viruses and cancer,” he says. “I was leaning toward cancer, but the SARS outbreak happened that year, so that made my decision.”
This moment sharpened his focus on a central question that has guided his work ever since: how do viruses enter human cells, and how can this process be blocked?
The Impact: Discovery and Contribution
Over 20 years, Dr. Li’s team has determined the structures of many viral entry proteins, including several landmark structures from high-risk viruses that have shaped the field.
In 2005, Dr. Li reported in Science the first detailed picture of how SARS-CoV-1 attaches to human cells. This discovery further revealed, at the atomic level, how just one or a few mutations in viral entry proteins can allow coronaviruses to jump from animals to people, cause infection, and spread.
When SARS-CoV-2 emerged years later, his earlier work gave the world a head start in understanding the new coronavirus. In early 2020, his team published findings in Nature that helped explain why SARS-CoV-2 spread so efficiently in people and which animals may have passed it to people. The work also informed efforts to develop vaccines and antibody therapies during the COVID-19 pandemic.
More recently, his team extended this work to the filovirus family. In a Nature study, they showed why Marburg virus enters human cells far more efficiently than Ebola virus and identified viral weaknesses that could be targeted to stop infection.
Today, Dr. Li co-leads a national antiviral drug discovery center, where his team works with collaborators to turn these insights into new treatments for viruses with pandemic potential.
The Purpose: Science with Responsibility
For Dr. Li, science is more than a profession. It comes with responsibility. His goal is to prepare for viral threats before they become crises by studying major virus families systematically.
For him, the purpose of virus research is simple: to reduce human suffering and help prevent future pandemics.
Dr. Li encourages aspiring scientists to build strong analytical skills and apply them to meaningful problems. At the same time, he emphasizes that important scientific questions require creativity and open-minded thinking.
When asked to complete the sentence, “I’m a scientist because…”, his answer is simple: “Because of the joy of new discoveries and the fulfillment of knowing that my work has helped the world.”