2XQL:
reference: Nucleoplasmin binds histone H2A-H2B dimers through its distal face., Ramos I, Martin-Benito J, Finn R, Bretana L, Aloria K, Arizmendi JM, Ausio J, Muga A, Valpuesta JM, Prado A, J Biol Chem. 2010 Oct 29;285(44):33771-8. Epub 2010 Aug 9. PMID: 20696766

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