During chromosomal DNA replication, the replicative helicase unwinds the duplex DNA to provide the single-stranded DNA substrate for the polymerase. In archaea, the replicative helicase is the minichromosome maintenance (MCM) complex. The enzyme utilizes the energy of ATP hydrolysis to translocate along one strand of the duplex and unwind the complementary strand. Much progress has been made in elucidating structure and function since the first report on the biochemical properties of an archaeal MCM protein in 1999. We now know the biochemical and structural properties of the enzyme from several archaeal species and some of the mechanisms by which the enzyme is regulated. This review summarizes recent studies on the archaeal MCM protein and discusses the implications for helicase function and DNA replication in archaea.
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Article Synopsis
- The study reveals how the CMG-like helicase and family D DNA polymerase (PolD) interact during DNA replication in the archaeon Thermococcus kodakarensis.
- The GINS complex, which includes Gins51 subunits, connects helicase to PolD, enabling coordinated leading and lagging strand synthesis in DNA replication.
- Crystal structure analysis and mutagenesis confirm the interaction, highlighting the importance of PolD in enhancing helicase activity and suggesting that this mechanism is conserved across Eukarya for efficient DNA replication.
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