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bioRxiv · 10.64898/2026.02.24.707417

Identification of a FANCD2-interacting protein motif (DIP-box) linking DNA Damage Response processes

Abstract

Repair of DNA damage is critical to genome integrity and the DNA clamp, FANCD2, is a major player in the response to interstrand crosslinks tying the two DNA strands together. It has long been suggested FANCD2 recruits other factors to coordinate repair these crosslinks, however it remains unclear if FANCD2 directly mediates this and how this is achieved. Here we show that FANCD2 has a conserved acidic region that directly recognises established DNA repair proteins containing a short linear motif. We discover new candidate interactors engaging with FANCD2 in a similar mode that are involved in histone modification, and RNA processing. Our data demonstrate FANCD2 is a hub for protein-protein interactions providing a structural explanation for FANCD2s central role in repair of DNA interstrand crosslinks. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/707417v2_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@10d0f59org.highwire.dtl.DTLVardef@6acac2org.highwire.dtl.DTLVardef@125a277org.highwire.dtl.DTLVardef@1cd4194_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Cao, Z., Briola, G. R., Ionita, C., Streetley, J., Walden, H. L., Rennie, M. L.. 2026-02-25. Identification of a FANCD2-interacting protein motif (DIP-box) linking DNA Damage Response processes. https://doi.org/10.64898/2026.02.24.707417

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