RAD51 paralog function in replicative DNA damage and tolerance

Area of Science:

• Molecular Biology
• Genetics
• Cancer Research

Background:

• Mutations in RAD51 paralog genes are linked to hereditary breast and ovarian cancers.
• RAD51 paralog defects classically cause homologous recombination (HR) deficiency and genomic instability.
• Recent studies explore non-canonical functions of RAD51 paralogs during DNA replication.

Purpose of the Study:

• To discuss the role of RAD51 paralogs and their complexes in responding to DNA replication stress.
• To highlight recent discoveries on RAD51 paralog functions in DNA lesion tolerance and fork restart.
• To describe the involvement of RAD51 paralog complexes in DNA damage response during replication.

Main Methods:

• Review of recent investigative advances and discoveries.
• Characterization of non-canonical RAD51 paralog functions.
• Analysis of RAD51 paralog complexes' roles in DNA replication stress response.

Main Results:

• RAD51 paralog complexes mediate lesion-specific tolerance to alkylating agents.
• The Shu complex is required for replication fork restart after dNTP depletion.
• BCDX2 complex regulates fork remodeling in response to dNTP pool fluctuations.
• RAD51C is essential for recognizing and tolerating methyl-adducts.

Conclusions:

• RAD51 paralog complexes are central to lesion recognition and bypass in a replication context.
• These complexes play critical roles in maintaining genomic integrity during DNA replication stress.
• Further research is needed to understand how these functions contribute to tumorigenesis.