A large-scale screen for mutagen-sensitive loci in Drosophila

Area of Science:

• Genetics
• Molecular Biology
• Developmental Biology

Background:

• DNA repair mechanisms are crucial for maintaining genomic integrity.
• Mutagen sensitivity screens in model organisms like Drosophila are vital for identifying novel genes involved in DNA repair.

Purpose of the Study:

• To identify new genes involved in DNA repair pathways in Drosophila.
• To characterize novel mutagen-sensitive mutants and their functions.

Main Methods:

• Conducted a large-scale screen of 6275 mutagenized Drosophila strains for hypersensitivity to methyl methanesulfonate (MMS) and nitrogen mustard (HN2).
• Analyzed second and third chromosomes separately to identify and categorize new mutants.
• Initiated molecular identification of newly discovered genes.

Main Results:

• Identified 18 mutants on the second chromosome, with 10 defining 8 new mutagen-sensitive genes (mus212-mus219).
• Identified 60 mutants on the third chromosome, with 16 defining 14 new mutagen-sensitive genes (mus314-mus327).
• Identified the Drosophila orthologs of yeast SNM1 (mus322) and human HEL308 (mus301).
• Discovered a mutant (mus215) affecting both DNA repair and meiotic recombination.

Conclusions:

• This study significantly expands the repertoire of known DNA repair genes in Drosophila.
• The identified genes provide new tools for studying DNA repair and its connection to other cellular processes like recombination.
• Alleles of the newly identified genes are available for further research.