Okazaki fragment processing during eukaryotic DNA replication

Journal article

Okazaki fragments containing an RNA primer are synthesised on the lagging strand of the eukaryotic replication fork. Major advances have recently been made in our understanding of the complex process of Okazaki fragment processing to form high molecular weight daughter DNA, identifying distinct stages. Firstly, primase synthesises an RNA primer which is rapidly extended into DNA by bound DNA polymerase α. DNA pol ε is then thought to synthesise the remainder of the fragment (50-200 nucleotides). The RNA primer is removed almost intact by RNaseH1, leaving a single ribonucleotide that is cleaved by the FEN-1 nuclease. DNA originally synthesised by pol α is replaced by DNA pol ε in co-operation with FEN-1. Finally, DNA ligase 1 seals the resulting nick by forming a phosphodiester bond between adjacent DNA nucleotides. A model whereby 2 these complex processes are modulated by DNA context and regulatory protein-protein interactions is presented.

Authors: Cox, L

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Yodosha
• Journal: Jikken Igaku (Experimental Medicine)
• Volume: 16
• Issue: 8
• Pages: 1031-1042
• Publication date: 1998-05-20
• Acceptance date: 1998-03-01
• ISSN: 0021-5031
• ISBN: 9784897060637
• Keywords: DNA polymerase; FEN1; DNA ligase 1; eukaryotic DNA replication; RNaseH1; PCNA; Okazaki fragments