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bioRxiv · 10.1101/2024.07.22.604623

STK19 positions TFIIH for cell-free transcription-coupled DNA repair

Mevissen, T. E. T.·Kuemmecke, M.·Schmid, E. W.·Farnung, L.·Walter, J. C.
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Abstract

In transcription-coupled repair, stalled RNA polymerase II (Pol II) is recognized by CSB and CRL4CSA, which co-operate with UVSSSA and ELOF1 to recruit TFIIH for nucleotide excision repair (TC-NER). To explore the mechanism of TC-NER, we recapitulated this reaction in vitro. When a plasmid containing a site-specific lesion is transcribed in frog egg extract, error-free repair is observed that depends on CSB, CRL4CSA, UVSSA, and ELOF1. Repair also depends on STK19, a factor previously implicated in transcription recovery after UV exposure. A 1.9 [A] cryo-electron microscopy structure shows that STK19 joins the TC-NER complex by binding CSA and the RPB1 subunit of Pol II. Furthermore, AlphaFold predicts that STK19 interacts with the XPD subunit of TFIIH, and disrupting this interface impairs cell-free repair. Molecular modeling suggests that STK19 positions TFIIH ahead of Pol II for lesion verification. In summary, our analysis of cell-free TC-NER suggests that STK19 couples RNA polymerase II stalling to downstream repair events.

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Mevissen, T. E. T., Kuemmecke, M., Schmid, E. W., Farnung, L., Walter, J. C.. 2024-07-23. STK19 positions TFIIH for cell-free transcription-coupled DNA repair. https://doi.org/10.1101/2024.07.22.604623

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