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bioRxiv · 10.1101/2022.01.18.476773

Identification of replication fork-associated proteins in Drosophila embryos and cultured cells using iPOND coupled to quantitative mass spectrometry

Munden, A.·Wright, M.·Han, D.·Tirgar, R.·Plate, L.·Nordman, J.
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Abstract

Replication of the eukaryotic genome requires the formation of thousands of replication forks that must work in concert to accurately replicate the genetic and epigenetic information. Defining replication fork-associated proteins is a key step in understanding how genomes are replicated and repaired in the context of chromatin to maintain genome stability. To identify replication fork-associated proteins, we performed iPOND (Isolation of Proteins on Nascent DNA) coupled to quantitative mass spectrometry in Drosophila embryos and cultured cells. We identified 76 and 278 fork-associated proteins in post-MZT embryos and Drosophila cultured S2 cells, respectively. By performing a targeted screen of a subset of these proteins, we demonstrate that BRWD3, a targeting specificity factor for the DDB1/Cul4 ubiquitin ligase complex (CRL4), functions at replication forks to promote fork progression and maintain genome stability. Altogether, our work provides a valuable resource for those interested in the DNA replication, repair and chromatin assembly during development.

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Munden, A., Wright, M., Han, D., Tirgar, R., Plate, L., Nordman, J.. 2022-01-20. Identification of replication fork-associated proteins in Drosophila embryos and cultured cells using iPOND coupled to quantitative mass spectrometry. https://doi.org/10.1101/2022.01.18.476773

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