5T2F

Structure of the FHA1 domain of Rad53 bound to the BRCT domain of Dbf4

Summary for 5T2F

• Entry DOI: 10.2210/pdb5t2f/pdb
• Related: 5T2S
• Descriptor: DDK kinase regulatory subunit DBF4,Serine/threonine-protein kinase RAD53 chimeric protein, 1,2-ETHANEDIOL (3 entities in total)
• Functional Keywords: fha; brct; protein chimera, cell cycle
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Total number of polymer chains: 4
• Total formula weight: 124590.30

Authors

Guarne, A.,Almawi, A.W.,Matthews, L.A. (deposition date: 2016-08-23, release date: 2017-03-15, Last modification date: 2023-10-04)

Primary citation

Almawi, A.W.,Matthews, L.A.,Myrox, P.,Boulton, S.,Lai, C.,Moraes, T.,Melacini, G.,Ghirlando, R.,Duncker, B.P.,Guarne, A.
'AND' logic gates at work: Crystal structure of Rad53 bound to Dbf4 and Cdc7.
Sci Rep, 6:34237-34237, 2016

PubMed Abstract: Forkhead-associated (FHA) domains are phosphopeptide recognition modules found in many signaling proteins. The Saccharomyces cerevisiae protein kinase Rad53 is a key regulator of the DNA damage checkpoint and uses its two FHA domains to interact with multiple binding partners during the checkpoint response. One of these binding partners is the Dbf4-dependent kinase (DDK), a heterodimer composed of the Cdc7 kinase and its regulatory subunit Dbf4. Binding of Rad53 to DDK, through its N-terminal FHA (FHA1) domain, ultimately inhibits DDK kinase activity, thereby preventing firing of late origins. We have previously found that the FHA1 domain of Rad53 binds simultaneously to Dbf4 and a phosphoepitope, suggesting that this domain functions as an 'AND' logic gate. Here, we present the crystal structures of the FHA1 domain of Rad53 bound to Dbf4, in the presence and absence of a Cdc7 phosphorylated peptide. Our results reveal how the FHA1 uses a canonical binding interface to recognize the Cdc7 phosphopeptide and a non-canonical interface to bind Dbf4. Based on these data we propose a mechanism to explain how Rad53 enhances the specificity of FHA1-mediated transient interactions.

PubMed: 27681475
DOI: 10.1038/srep34237

Experimental method

X-RAY DIFFRACTION (2.66 Å)