Map of synthetic rescue interactions for the Fanconi anemia DNA repair pathway identifies USP48

Area of Science:

• Genetics
• Molecular Biology
• Cancer Research

Background:

• Defective DNA repair leads to genetic diseases with severe phenotypes.
• Fanconi anemia (FA) is a rare genetic disorder caused by faulty DNA interstrand crosslink (ICL) repair, resulting in bone marrow failure, developmental issues, and cancer predisposition.

Purpose of the Study:

• To identify genetic modifiers that confer resistance to genotoxic stress in FA-defective cells.
• To investigate the role of USP48 in DNA repair pathways relevant to Fanconi anemia.

Main Methods:

• Genome-wide loss-of-function screens were performed on human haploid isogenic FA-defective cell lines (FANCA, FANCC, FANCG, FANCI, FANCD2).
• Sensitivity to ICL agents and DNA damage clearance were assessed in FA-deficient cells with and without USP48.
• Chromosomal instability was evaluated in FA-defective cells with USP48 inactivation.

Main Results:

• USP48 was identified as a synthetic viable gene for FA-gene deficiencies.
• FA-deficient cells lacking USP48 showed reduced sensitivity to ICL agents and enhanced BRCA1-dependent DNA damage clearance.
• Inactivation of USP48 led to decreased chromosomal instability in FA-defective cells.

Conclusions:

• USP48 plays a role in regulating DNA repair mechanisms.
• USP48 inactivation represents a potential therapeutic target for Fanconi anemia, improving cellular resistance to genotoxic stress.