Stephen P. Bell is a biochemist recognized for his work on the molecular mechanisms of the initiation of DNA replication in eukaryotic cells. He is known particularly for his discovery and characterization of a protein complex that recognizes the genomic sites at which DNA replication starts and his characterization of the events that select these sites. Bell was born in Ann Arbor, Michigan and grew up in Nashville, Tennessee. He graduated from Northwestern University in Evanston, Illinois with Degrees from the Integrated Science Program and the Biochemistry, Molecular Biology and Cell Biology (BMBCB) Department in 1985 and the University of California, Berkeley with a PhD. In Biochemistry in 1990 where he worked with Robert Tjian. He was a postdoctoral fellow at Cold Spring Harbor Laboratories with Bruce Stillman. He joined the Biology Department faculty at the Massachusetts Institute of Technology in 1994. Bell is a Howard Hughes Medical Institute Investigator and received the 2001 ASBMB-Schering Plough Scientific Achievement Award and the 2009 National Academy of Sciences Award in Molecular Biology.

Research Interests

Stephen P. Bell's laboratory is interested studying the assembly of the multi-enzyme replisomes that replicate animal chromosomes and how these events are regulated during the cell cycle to ensure maintenance of the genome. Bell discovered the Origin Recognition Complex (ORC), the protein complex that identifies eukaryotic origins of replication and his lab has characterized the functions of this complex and used its genomic binding sites to identify origins of replication in multiple organisms. His lab pioneered methods to monitor association of replication proteins with the DNA in cells to identify components of the replication fork and the proteins involved in loading a key protein required for DNA replication, the replicative DNA helicase, at origins of replication. Their studies have contributed to understanding the mechanisms that ensure the genome is replicated only once per round of cell division. Most recently, they have used single-molecule biochemical studies in collaboration with Jeff Gelles' lab at Brandeis to understand the protein dynamics during replicative helicase loading and provide insights into the mechanisms that establish bidirectional replication initiation.

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Primary Section

Section 21: Biochemistry

Secondary Section

Section 22: Cellular and Developmental Biology