Ian MacRae serves as a scientific advisor to City Therapeutics. He is a professor at the Scripps Research Institute in La Jolla, California, where his laboratory investigates the structure and function of Argonaute proteins—core components of RNA silencing pathways.

Dr. MacRae’s group determined the first crystal structure of human Argonaute2 and has since reported more than two dozen additional structures of Argonaute2 bound to natural and chemically modified siRNAs and their target RNAs. These studies have provided detailed insights into how small RNAs engage their targets and have informed the design of next-generation RNA therapeutics. His research combines structural biology and biochemistry to uncover the molecular rules that govern siRNA activity, including how chemical modifications affect Argonaute binding and function.

Dr. MacRae earned his Ph.D. in 2001 from the University of California, Davis, where he studied the structure and mechanism of sulfate-activation enzymes. He conducted postdoctoral research with Jennifer Doudna at the University of California, Berkeley, where he determined the crystal structure of Dicer, the enzyme that produces siRNAs. During this time, he was named a fellow of the Life Sciences Research Foundation. As a faculty member, he was named a Pew Scholar in the Biomedical Sciences.