Study of UV Sensitivity on mus109 and Marionette Gene Rescue

The mus109 gene in Drosophila melanogaster, homologous to human DNA2, plays a critical role in DNA repair and genomic stability. Mutations in mus109 increase sensitivity to DNA-damaging agents like UV radiation. This study investigates whether the marionette (mrn) gene, which encodes a subunit of the TFIIH complex also involved in DNA repair, can rescue the UV-sensitive phenotype of mus109IS mutants. Survival assays were conducted using various UV exposure times on progeny from crosses between mus109IS mutants and either mus109D2 or mrn mutants. Results confirmed the UV sensitivity of mus109IS/mus109D2 flies, while mus109IS/mrn progeny exhibited increased survival, suggesting a potential compensatory role of the mrn gene in DNA repair. Despite some experimental challenges, such as fly escape and timing inconsistencies, the findings support further exploration of genetic interactions between mus109 and mrn in DNA damage response pathways. This work enhances our understanding of conserved mechanisms of genome maintenance relevant to human health and disease.