6FF4:
reference: Structure and Conformational Dynamics of the Human Spliceosomal B(act) Complex., Haselbach D, Komarov I, Agafonov DE, Hartmuth K, Graf B, Dybkov O, Urlaub H, Kastner B, Luhrmann R, Stark H, Cell. 2018 Jan 25;172(3):454-464.e11. doi: 10.1016/j.cell.2018.01.010. Epub 2018 , Jan 17. PMID: 29361316

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