4DWR:
reference: Structural and mechanistic insights into guanylylation of RNA-splicing ligase RtcB joining RNA between 3'-terminal phosphate and 5'-OH., Englert M, Xia S, Okada C, Nakamura A, Tanavde V, Yao M, Eom SH, Konigsberg WH, Soll D, Wang J, Proc Natl Acad Sci U S A. 2012 Sep 18;109(38):15235-40. Epub 2012 Sep 4. PMID: 22949672

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