CometChip Enables Parallel Analysis of Multiple DNA Repair Activities

Ge, J.; Ngo, L. P.; Kaushal, S.; Tay, I. J.; Thadhani, E.; Kay, J. E.; Mazzucato, P.; Chow, D. N.; Fessler, J. L.; Weingeist, D. M.; Sobol, R. W.; Samson, L. D.; Floyd, S. R.; Engelward, B. P.

doi:10.1101/2021.01.19.427336

bioRxiv · 10.1101/2021.01.19.427336

CometChip Enables Parallel Analysis of Multiple DNA Repair Activities

Ge, J.·Ngo, L. P.·Kaushal, S.·Tay, I. J.·Thadhani, E.·Kay, J. E.·Mazzucato, P.·Chow, D. N.·Fessler, J. L.·Weingeist, D. M.·Sobol, R. W.·Samson, L. D.·Floyd, S. R.·Engelward, B. P.

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Abstract

DNA damage can be cytotoxic and mutagenic and is directly linked to aging, cancer, and heritable diseases. To counteract the deleterious effects of DNA damage, cells have evolved highly conserved DNA repair pathways. Many commonly used DNA repair assays are relatively low throughput and are limited to analysis of one protein or one pathway. Here, we have explored the capacity of the CometChip platform for parallel analysis of multiple DNA repair activities. Taking advantage of the versatility of the traditional comet assay and leveraging micropatterning techniques, the CometChip platform offers increased throughput and sensitivity compared to the traditional comet assay. By exposing cells to DNA damaging agents that create substrates of Base Excision Repair, Nucleotide Excision Repair, and Non-Homologous End Joining, we show that the CometChip is an effective method for assessing repair deficiencies in all three pathways. With these advanced applications of the CometChip platform, we expand the efficacy of the comet assay for precise, high-throughput, parallel analysis of multiple DNA repair activities.

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Ge, J., Ngo, L. P., Kaushal, S., Tay, I. J., Thadhani, E., Kay, J. E., Mazzucato, P., Chow, D. N., Fessler, J. L., Weingeist, D. M., Sobol, R. W., Samson, L. D., Floyd, S. R., Engelward, B. P.. 2021-01-20. CometChip Enables Parallel Analysis of Multiple DNA Repair Activities. https://doi.org/10.1101/2021.01.19.427336

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