Investigating the redox properties of human DNA primase

Abstract

Human DNA primase is a heterodimeric, DNA- dependent RNA polymerase that initiates replication on single- stranded DNA. Primase has been shown previously to contain a [4Fe4S] cluster cofactor in the C terminal domain of its large subunit (p58C) . Here we measure the redox activity of the [4Fe4S] domain of primase (p58C) using electrochem. on a DNA- modified gold electrode. P58C is found to be electrochem. active on duplex DNA substrates with a single- stranded DNA overhang. Binding of p58C to the DNA substrate, moreover, is found to be dependent both on oxidn. state of the [4Fe4S] cluster and on the presence of nucleotide triphosphates (NTPs) . Through these studies, we are exploring how DNA charge transport may be exploited by DNA primase in order to execute the multistep, coordinated process of replication initiation.

Additional details