Drosophila ATM and ATR have distinct activities in the regulation of meiotic DNA damage and repair.
Ataxia telangiectasia-mutated (ATM) and ataxia telangiectasia-related (ATR) kinases are conserved regulators of cellular responses to double strand breaks (DSBs). During meiosis, however, the functions of these kinases in DSB repair and the deoxyribonucleic acid (DNA) damage checkpoint are unclear. In this paper, we show that ATM and ATR have unique roles in the repair of meiotic DSBs in Drosophila melanogaster. ATR mutant analysis indicated that it is required for checkpoint activity, whereas ATM may not be. Both kinases phosphorylate H2AV (γ-H2AV), and, using this as a reporter for ATM/ATR activity, we found that the DSB repair response is surprisingly dynamic at the site of DNA damage. γ-H2AV is continuously exchanged, requiring new phosphorylation at the break site until repair is completed. However, most surprising is that the number of γ-H2AV foci is dramatically increased in the absence of ATM, but not ATR, suggesting that the number of DSBs is increased. Thus, we conclude that ATM is primarily required for the meiotic DSB repair response, which includes functions in DNA damage repair and negative feedback control over the level of programmed DSBs during meiosis.
Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854, USA.
Eric F
EF
Joyce
Michael
M
Pedersen
Stanley
S
Tiong
Sanese K
SK
White-Brown
Anshu
A
Paul
Shelagh D
SD
Campbell
Kim S
KS
McKim
D000818:Animals; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D004249:DNA Damage; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D005453:Fluorescence; D008540:Meiosis; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism
D018797:Cell Cycle Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D025521:Tumor Suppressor Proteins; D064007:Ataxia Telangiectasia Mutated Proteins; C444435:Mei-41 protein, Drosophila; D017346:Protein Serine-Threonine Kinases