7LTO

Nse5-6 complex

Summary for 7LTO

• Entry DOI: 10.2210/pdb7lto/pdb
• EMDB information: 23517
• Descriptor: Non-structural maintenance of chromosome element 5, Ubiquitin-like protein SMT3,DNA repair protein KRE29 chimera (2 entities in total)
• Functional Keywords: smc5/6, nse5-6, nse5, nse6, complex, sumo-binding, structural protein
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Total number of polymer chains: 2
• Total formula weight: 132922.14

Authors

Yu, Y.,Li, S.B.,Zheng, S.,Tangy, S.,Koyi, C.,Wan, B.B.,Kung, H.H.,Andrej, S.,Alex, K.,Patel, D.J.,Zhao, X.L. (deposition date: 2021-02-19, release date: 2021-05-19, Last modification date: 2024-03-06)

Primary citation

Yu, Y.,Li, S.,Ser, Z.,Sanyal, T.,Choi, K.,Wan, B.,Kuang, H.,Sali, A.,Kentsis, A.,Patel, D.J.,Zhao, X.
Integrative analysis reveals unique structural and functional features of the Smc5/6 complex.
Proc.Natl.Acad.Sci.USA, 118:-, 2021

PubMed Abstract: Structural maintenance of chromosomes (SMC) complexes are critical chromatin modulators. In eukaryotes, the cohesin and condensin SMC complexes organize chromatin, while the Smc5/6 complex directly regulates DNA replication and repair. The molecular basis for the distinct functions of Smc5/6 is poorly understood. Here, we report an integrative structural study of the budding yeast Smc5/6 holo-complex using electron microscopy, cross-linking mass spectrometry, and computational modeling. We show that the Smc5/6 complex possesses several unique features, while sharing some architectural characteristics with other SMC complexes. In contrast to arm-folded structures of cohesin and condensin, Smc5 and Smc6 arm regions do not fold back on themselves. Instead, these long filamentous regions interact with subunits uniquely acquired by the Smc5/6 complex, namely the Nse2 SUMO ligase and the Nse5/Nse6 subcomplex, with the latter also serving as a linchpin connecting distal parts of the complex. Our 3.0-Å resolution cryoelectron microscopy structure of the Nse5/Nse6 core further reveals a clasped-hand topology and a dimeric interface important for cell growth. Finally, we provide evidence that Nse5/Nse6 uses its SUMO-binding motifs to contribute to Nse2-mediated sumoylation. Collectively, our integrative study identifies distinct structural features of the Smc5/6 complex and functional cooperation among its coevolved unique subunits.

PubMed: 33941673
DOI: 10.1073/pnas.2026844118

Experimental method

ELECTRON MICROSCOPY (3.2 Å)