Joan Steitz, a Sterling professor of molecular biophysics and biochemistry, on Tuesday received this year’s Lasker-Koshland Special Achievement Award in Medical Science, one of the nation’s most prestigious prizes in medicine.

Steitz was recognized for her “four decades of leadership in biomedical science — exemplified by pioneering discoveries in RNA biology, generous mentorship of budding scientists and vigorous and passionate support of women in science,” according to the Albert and Mary Lasker Foundation. The Lasker awards have been presented annually since 1945 to people who have made significant contributions to medical science or performed public service on behalf of medicine.

“When I first started out, we knew that DNA made RNA, which made proteins, and RNA was the middle molecule. Since then, there have been fabulous discoveries of new kinds of RNA that are pivotal in regulation of gene expression,” Steitz told the News. “We’ve made several of those discoveries, and it’s contributed to a lot of what we understand about disease and how living things work. I’m very pleased and proud to have been a part of that.”

On Thursday, the School of Medicine held a reception in the Medical Historical Library to celebrate Steitz’s award. At the event, Steitz expressed gratitude to the University, praising its scientific environment.

Akiko Iwasaki, a professor of immunobiology and molecular, cellular and developmental biology, took to Twitter to express how moved she was by Steitz’s speech.

“Joan Steitz, in her Lasker award reception @yalemed, credits everyone in the audience for the award — for creating environment to do science. That was her speech. Not a word about herself, the obstacles she had to overcome, or her iconic discoveries. I am sobbing. #inspiration,” she wrote.

Steitz has made key contributions to the study of the nature and function of RNA, the messenger molecule that provides ribosomes with instructions to produce proteins. Her lab is best known for the discovery of small nuclear ribonucleoproteins, known as snRNPs, which play a pivotal role in gene expression. She found that snRNPs are essential in splicing, a process that cuts out noncoding RNA segments before the sequence can be used in the process of making proteins.

Steitz has made countless other breakthroughs that have transformed our understanding of RNA in biological function and disease. These include the discoveries of small nucleolar RNAs, which modify other types of RNAs, and microRNAs, which help stabilize messenger RNA molecules.

Steitz, a Howard Hughes Medical Institute investigator, was also recognized for her mentorship of scientists and advocacy for women in science.

Steitz has pioneered the way for women scientists through her scientific achievements as well as through her advocacy for women in science. In 2006, she co-wrote a National Academy of Sciences report that described the barriers to the participation of women in sciences and called for a more inclusive and equitable future.

“She has contributed so much to the field of RNA biology, made a lot of sacrifices, cared for so many young scientists and helped them through their career path,” said Seyed Torabi, a postdoctoral fellow in Steitz’s lab. “She is not only a superstar scientist but also a role model for young scientists.”

“Joan is so very approachable, warm and caring. She encourages you to push through despite the setbacks and pitfalls of experimental science,” said Vanessa Mondol, a postdoctoral associate in Steitz’s lab.

Mentoring young scientists and sharing the joy of a younger person making a discovery is one of the most rewarding aspects of working as a researcher, Steitz said.

At Thursday’s reception, several members of her lab, including postdoctoral fellows and graduate students, reflected on their experiences with her.

“In the lab, she motivates me and others to pursue challenging research questions and provides her guidance on them every week,” said Nicolle Rosa Mercado GRD ’22, who works in Steitz’s lab. “Through these interactions, she continues to awe me with her brilliance, modesty and empathy.”

Steitz’s encouragement and belief in her students is unparalleled, Paulina Pawlica, a postdoctoral associate in the lab, said at the reception. She has influenced the lives of countless people, both professionally and personally, Pawlica added.

“This influence is not limited to the people in our lab, but also includes many scientists all over the world who consider her as their ‘role model,’” she said.

Steitz, who has taught courses such as “Principles of Biochemistry II” and “Medical Impact of Basic Science” in Yale College, is admired by her students and peers as an engaging and knowledgeable professor.

“Dr. Steitz was a fabulous professor for MB&B 301 [‘Principles of Biochemistry II’], always pausing to answer our questions. I was a junior then and was so impressed with her command of the subject,” said Sandy Chang, the associate dean for science and quantitative reasoning education.

Years later, he added, Steitz was welcoming to him when he petitioned to join the MB&B department as a faculty member.

Steitz and the other three Lasker recipients will receive their $250,000 awards at a ceremony on Sept. 21 in New York.

Amy Xiong | amy.xiong@yale.edu