A folded conformation of MukBEF and cohesin

Autor: Byung-Gil Lee, Frank Bürmann, Thane Than, Jan Löwe, Bin Hu, Juri Rappsilber, Ludwig Sinn, Francis J. O’Reilly, Kim Nasmyth, Stanislau Yatskevich
Rok vydání: 2019
Předmět:
Zdroj: Nature Structural & Molecular Biology. 26:227-236
ISSN: 1545-9985
1545-9993
Popis: Structural maintenance of chromosomes (SMC)-kleisin complexes organize chromosomal DNAs in all domains of life, where they have key roles in chromosome segregation, DNA repair and regulation of gene expression. They function through topological entrapment and active translocation of DNA, but the underlying conformational changes are largely unclear. Using structural biology, mass spectrometry and cross-linking, we investigated the architecture of two evolutionarily distant SMC-kleisin complexes: proteobacterial MukBEF and eukaryotic cohesin. We show that both contain a dynamic coiled-coil discontinuity, the elbow, near the middle of their arms that permits a folded conformation. Bending at the elbow brings into proximity the hinge dimerization domain and the head/kleisin module, situated at opposite ends of the arms. Our findings favor SMC activity models that include a large conformational change in the arms, such as a relative movement between DNA contact sites during DNA loading and translocation.
Databáze: OpenAIRE