Replication origin selection regulates the distribution of meiotic recombination

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• The DNA replication program, characterized by origin activation timing and location, changes during development and in cancer.
• The role of altered origin usage in regulating specific biological processes, such as meiosis, is not well understood.

Purpose of the Study:

• To investigate the impact of modifying DNA replication origin selection on meiosis in fission yeast.
• To determine if changes in origin usage influence meiotic progression and recombination.

Main Methods:

• Genome-wide analysis of replication programs in premeiotic S phase.
• Manipulation of origin efficiencies by altering Cdc45 replication factor expression.
• Assessment of Rad51 recombination factor binding and recombination frequencies.

Main Results:

• Genome-wide alterations in the replication program did not affect meiotic progression.
• Local changes in origin efficiencies significantly altered Rad51 binding and recombination frequencies.
• Targeting Cdc45 expression to modify origin efficiencies yielded similar results for Rad51.

Conclusions:

• Origin selection is a critical factor in organizing meiotic recombination.
• Modifications in the DNA replication program can influence cellular physiology, specifically meiotic recombination.