5U6K:
reference: Structural Insight into BLM Recognition by TopBP1., Sun L, Huang Y, Edwards RA, Yang S, Blackford AN, Niedzwiedz W, Glover JNM, Structure. 2017 Sep 1. pii: S0969-2126(17)30258-7. doi:, 10.1016/j.str.2017.08.005. PMID: 28919440

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