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The structural basis of Cdc7-Dbf4 kinase dependent targeting and phosphorylation of the MCM2-7 double hexamer

ABSTRACT: The controlled assembly of replication forks is critical for genome stability. The Dbf4-dependent Cdc7 kinase (DDK) initiates replisome assembly by phosphorylating the MCM2-7 replicative helicase at the N-terminal tails of Mcm2, Mcm4 and Mcm6. At present, it remains poorly understood how DDK docks onto the helicase and how the kinase targets distal Mcm subunits for phosphorylation. By cryo-electron microscopy and biochemical analysis we discovered that an interaction between the HBRCT domain of Dbf4 with Mcm2 serves as an anchoring point, which supports binding of DDK across the MCM2-7 double-hexamer interface and phosphorylation of Mcm4 on the opposite hexamer. Moreover, a rotation of DDK along its anchoring point allows phosphorylation of Mcm2 and Mcm6 on opposite hexamers. In summary, our work provides fundamental insights in the DDK structure, control and the selective activation of the MCM2-7 helicase during DNA replication, which can be exploited for development of novel DDK inhibitors.

INSTRUMENT(S): Q Exactive HF-X

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast) Saccharomyces Cerevisiae

SUBMITTER: Alex Montoya

LAB HEAD: Dr Pavel Shliaha

PROVIDER: PXD031315 | Pride | 2022-05-31

REPOSITORIES: Pride

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			Action	DRS
	Swissprot_S_cerevisiae_4932_20200924.fasta	Fasta
	b026p081_DN1.raw	Raw
	b026p081_DN2.raw	Raw
	b026p081_DN3.raw	Raw
	b026p081_N1.raw	Raw

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