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Interactions between two catalytically distinct MCM subgroups are essential for coordinated ATP hydrolysis and DNA replication.

A Schwacha·S P Bell
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Abstract

The six MCM (minichromosome maintenance) proteins are essential DNA replication factors that each contain a putative ATP binding motif and together form a heterohexameric complex. We show that these motifs are required for viability in vivo and coordinated ATP hydrolysis in vitro. Mutational analysis discriminates between two functionally distinct MCM protein subgroups: Mcm4p, 6p, and 7p contribute canonical ATP binding motifs essential for catalysis, whereas the related motifs in Mcm2p, 3p, and 5p serve a regulatory function. Reconstitution experiments indicate that specific functional interactions between these two subgroups are required for robust ATP hydrolysis. Our observations show parallels between the MCM complex and the F1-ATPase, and we discuss how ATP hydrolysis by the MCM complex might be coupled to DNA strand separation.

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Adenosine TriphosphatasesAdenosine TriphosphateAmino Acid MotifsDNA ReplicationFlow CytometryHydrolysisMacromolecular SubstancesMinichromosome Maintenance 1 ProteinProtein SubunitsProton-Translocating ATPasesSchizosaccharomycesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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A Schwacha, S P Bell. 2001. Interactions between two catalytically distinct MCM subgroups are essential for coordinated ATP hydrolysis and DNA replication.. https://doi.org/10.1016/s1097-2765(01)00389-6

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