We sadly announce that MCB Professor Emeritus Fred Wilt died on January 30, 2026, at the age of 91, after 62 years on the faculty at UC Berkeley. Fred was born December 12, 1934, in Nappanee, Indiana. Some of Fred’s ancestors had come to this continent well before the American Revolution, while others came from Germany in the 19th century. Fred was a third generation (or so) Hoosier. His father and maternal grandmother ran the Huffman Bakery in Nappanee, where Fred also worked as a youth. Notwithstanding this artisanal background, academics also ran strong in the Wilt family. Fred’s younger brother Alan F. Wilt was a distinguished World War II historian at the University of Iowa, and after moving to Arizona, their father Lisle taught at Arizona State University.
Fred received an AB degree in Zoology in 1956, from Indiana University, where he was a varsity debater and was named the outstanding junior pre-medical student. After a summer research experience at Woods Hole Marine Biology Laboratory, however, he decided he would pursue a career in research and teaching. After getting a PhD from Johns Hopkins, followed by stints at the University of Liverpool, College de France, Stanford, and Purdue, Fred brought the “new developmental biology” to Berkeley in 1964, rising to Professor of Zoology in 1968. After the reorganization of biology departments that led to the founding of MCB, Fred served as the inaugural Division Head for what was then the Division of Cell & Developmental Biology, becoming Professor of the Graduate School in 1994.
Fred’s career spanned almost the entirety of the molecular era to date. John Gurdon’s nuclear transplant experiments in Xenopus suggested that the emergence of distinct cell types in developing embryos did not rely on progressively discarding unwanted genes. Thus, it must be that differential gene activity was key, but how is this achieved? In a 1966 essay in American Zoologist, Fred, summarized and evaluated the emerging “messenger RNA hypothesis….that the product of a gene is an RNA molecule which is a complementary copy of the DNA sequence of a gene”, and that messenger RNA somehow mediated differential gene expression.
Attacking this problem in the 1960s was not for the faint of heart. Absent any of the tools we rely on today, and before Drosophila and Caenorhabditis enabled genetic approaches to development, Fred and colleagues applied biochemical methods to study the processing of abundant RNAs, first focusing on chick embryo hemoglobin, and then taking on sea urchins (chiefly Lytechinus pictus and Strongylocentrotus purpuratus), which can be manipulated to obtain millions of synchronous, highly transparent embryos. In his early sea urchin work, Fred’s group studied the polyadenylation of mRNAs and histone biosynthesis. In the last few decades of his career, Fred used emerging cellular, molecular, and genomic tools to focus on early sea urchin larval development. Fred and his colleagues identified, isolated, and characterized genes and their cognate proteins that are involved in the formation of the larval skeleton with its unique physical properties. His group participated in the research consortium that reported the sequencing and characterizing the S. purpuratus genome in 2006. Subsequently, his group examined the roles of amorphous calcium carbonate and integral endoskeletal proteins in sea urchin biomineralization.
In addition to the many graduate students and postdocs who trained with Fred, he influenced thousands of Berkeley undergraduates through his participation in the introductory Bio 1A course starting in the 1960s. He was chosen as one of the first lecturers in the course and taught at least 10 additional times in subsequent years. Later, he taught in undergraduate and graduate developmental biology courses, and in his last years in a popular non-majors class on Genetics and Society, consistent with his belief in the importance of such information for any well-educated person of the 21st century. Fred reported that a retired doctor sat in on the whole course because he wanted to learn what advances had been made since his time in medical school.
Fred’s unstinting service to the Zoology and MCB departments, the Berkeley campus and the larger scientific community is too extensive to present in detail. However, examples included chairing the search committee that brought a young Ray Keller to Zoology in 1980, catalyzing a golden age of embryology on this campus. Fred’s work on sea urchin led to extensive connections with Japanese, European and Israeli scientists. He was appropriately honored as Fellow of the American Association for the Advancement of Science, the Guggenheim Foundation, and the Japan Society for the Promotion of Science, was an NIH Merit awardee, and was selected twice for Miller Research Professorships. Fred is survived by his loving wife of 38 years, Diane Wilt, and their children.