Lyle Simmons

Our research is focused on studies of mismatch repair, DNA replication homologous recombination and the interplay between these pathways. Mismatch repair corrects DNA polymerase errors that escape the proofreading activity of the replicative polymerases. Mismatch repair contributes to the overall fidelity of the replication pathway ~1000-fold. Nearly half of all hereditary nonpolyposis colorectal cancers (HNPCC) are linked to defects in mismatch repair. We study the universal mechanisms of mismatch repair in the experimentally tractable organism B. subtilis.  Like most organisms B. subtilis contains the highly conserved MutS and MutL proteins. Unlike the typical bacterial model E. coli, B. subtilis lacks the methyl-directed repair pathway characterized by the presence of DNA adenine methylase (Dam) and the endonuclease MutH. We combine live cell imaging with genetics and biochemistry to understand the cellular mechanisms that control mismatch repair protein recruitment to mismatches in vivo.

Dr. Simmons received his B.S. in Biology from Alma College, and his Ph.D. in Biochemistry and Molecular Biology from Michigan State University. He was an NIH Postdoctoral Fellow in the Department of Biology at the Massachusetts Institute of Technology before joining the University of Michigan faculty in September 2008.

Field(s) of Study

• DNA mismatch repair, replication and recombination

Areas of Focus

• Biochemistry
• Cell Biology
• Development
• Microbiology