Mutation spectrum data for Saccharomyces cerevisiae psf1-1 pol2-M644G mutants

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• DNA replication is crucial for cell division, with distinct polymerases handling leading and lagging strands.
• Polymerase epsilon (Pol ε) primarily synthesizes the leading strand, while Polymerase delta (Pol δ) handles the lagging strand in eukaryotes.
• The GINS complex, along with Cdc45 and Mcm2-7, forms the CMG helicase complex, essential for recruiting Pol ε.

Purpose of the Study:

• To analyze the contribution of Pol ε to DNA replication in yeast with a defective GINS complex.
• To investigate how impaired CMG helicase function affects the roles of DNA polymerases.
• To observe changes in mutational spectra resulting from altered DNA replication dynamics.

Main Methods:

• Utilized the pol2-M644G mutant allele of Pol ε to track its activity.
• Employed the psf1-1 mutant allele affecting the GINS complex in *Saccharomyces cerevisiae*.
• Analyzed DNA sequencing data from the URA3 reporter gene in different orientations relative to ARS.

Main Results:

• Observed alterations in mutational spectra within the URA3 reporter gene.
• Data suggest a shift in polymerase activity during replication under impaired CMG helicase function.
• The study supports findings of increased Pol δ involvement in leading strand replication.

Conclusions:

• Impaired CMG helicase complex function influences DNA polymerase recruitment and activity.
• This can lead to an increased contribution of DNA polymerase delta to leading strand synthesis.
• Understanding these dynamics is vital for comprehending genome stability and replication fidelity.