5OMB

Crystal structure of K. lactis Ddc2 N-terminus in complex with S. cerevisiae Rfa1 N-OB domain

Summary for 5OMB

• Entry DOI: 10.2210/pdb5omb/pdb
• Descriptor: Replication factor A protein 1, DNA damage checkpoint protein LCD1, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: oligonucleotide-binding fold, coiled-coil domain, complex, nucleus, protein binding
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Cellular location: Nucleus: P22336; Cytoplasm : Q6CUV9
• Total number of polymer chains: 4
• Total formula weight: 57295.52

Authors

Deshpande, I.,Seeber, A.,Shimada, K.,Keusch, J.J.,Gut, H.,Gasser, S.M. (deposition date: 2017-07-28, release date: 2017-10-25, Last modification date: 2024-11-06)

Primary citation

Deshpande, I.,Seeber, A.,Shimada, K.,Keusch, J.J.,Gut, H.,Gasser, S.M.
Structural Basis of Mec1-Ddc2-RPA Assembly and Activation on Single-Stranded DNA at Sites of Damage.
Mol. Cell, 68:431-445.e5, 2017

PubMed Abstract: Mec1-Ddc2 (ATR-ATRIP) is a key DNA-damage-sensing kinase that is recruited through the single-stranded (ss) DNA-binding replication protein A (RPA) to initiate the DNA damage checkpoint response. Activation of ATR-ATRIP in the absence of DNA damage is lethal. Therefore, it is important that damage-specific recruitment precedes kinase activation, which is achieved at least in part by Mec1-Ddc2 homodimerization. Here, we report a structural, biochemical, and functional characterization of the yeast Mec1-Ddc2-RPA assembly. High-resolution co-crystal structures of Ddc2-Rfa1 and Ddc2-Rfa1-t11 (K45E mutant) N termini and of the Ddc2 coiled-coil domain (CCD) provide insight into Mec1-Ddc2 homodimerization and damage-site targeting. Based on our structural and functional findings, we present a Mec1-Ddc2-RPA-ssDNA composite structural model. By way of validation, we show that RPA-dependent recruitment of Mec1-Ddc2 is crucial for maintaining its homodimeric state at ssDNA and that Ddc2's recruitment domain and CCD are important for Mec1-dependent survival of UV-light-induced DNA damage.

PubMed: 29033322
DOI: 10.1016/j.molcel.2017.09.019

Experimental method

X-RAY DIFFRACTION (1.94 Å)