'Proofreading' proteins stop and reel in DNA to correct replication errors

On the DNA assembly line, two proofreading proteins work together as an emergency stop button to prevent replication errors. New research from North Carolina State University and the University of North Carolina at Chapel Hill shows how these proteins—MutL and MutS—prevent DNA replication errors by creating an immobile structure that calls more proteins to the site to repair the error. This structure could also prevent the mismatched region from being "packed" back into the cell during division.