The Condensin Complex Is A Mechanochemical Motor That Translocates Along DNA

Abstract

One Sentence SummarySingle-molecule imaging reveals that eukaryotic condensin is a highly processive DNA-translocating motor complex.\n\nAbstractCondensin plays crucial roles in chromosome organization and compaction, but the mechanistic basis for its functions remains obscure. Here, we use single-molecule imaging to demonstrate that Saccharomyces cerevisiae condensin is a molecular motor capable of ATP hydrolysis-dependent translocation along double-stranded DNA. Condensins translocation activity is rapid and highly processive, with individual complexes traveling an average distance of [≥]10 kilobases at a velocity of [~]60 base pairs per second. Our results suggest that condensin may take steps comparable in length to its [~]50-nanometer coiled-coil subunits, suggestive of a translocation mechanism that is distinct from any reported DNA motor protein. The finding that condensin is a mechanochemical motor has important implications for understanding the mechanisms of chromosome organization and condensation.