Condensin Smc2-Smc4 Dimers Are Flexible and Dynamic

Condensin Smc2-Smc4 Dimers Are Flexible and Dynamic

Eeftens, J.M. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)
Katan, A.J. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)
Kschonsak, Marc (European Molecular Biology Laboratory)
Hassler, Markus (European Molecular Biology Laboratory)
de Wilde, L. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)
Dief, Essam M. (Kavli institute of nanoscience Delft)
Haering, Christian H. (European Molecular Biology Laboratory)
Dekker, C. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)

2016-03-01

Structural maintenance of chromosomes (SMC) protein complexes, including cohesin and condensin, play key roles in the regulation of higher-order chromosome organization. Even though SMC proteins are thought to mechanistically determine the function of the complexes, their native conformations and dynamics have remained unclear. Here, we probe the topology of Smc2-Smc4 dimers of the S. cerevisiae condensin complex with high-speed atomic force microscopy (AFM) in liquid. We show that the Smc2-Smc4 coiled coils are highly flexible polymers with a persistence length of only ~4 nm. Moreover, we demonstrate that the SMC dimers can adopt various architectures that interconvert dynamically over time, and we find that the SMC head domains engage not only with each other, but also with the hinge domain situated at the other end of the ~45-nm-long coiled coil. Our findings reveal structural properties that provide insights into the molecular mechanics of condensin complexes.

http://resolver.tudelft.nl/uuid:ceccb0c9-74a6-42bb-ae5f-7f65b3104b77

https://doi.org/10.1016/j.celrep.2016.01.063

2211-1247

Cell Reports, 14 (8), 1813-1818

Institutional Repository

journal article

© 2016 J.M. Eeftens, A.J. Katan, Marc Kschonsak, Markus Hassler, L. de Wilde, Essam M. Dief, Christian H. Haering, C. Dekker