3F31:
reference: Crystal structure of the nonerythroid alpha-spectrin tetramerization site reveals differences between erythroid and nonerythroid spectrin tetramer formation., Mehboob S, Song Y, Witek M, Long F, Santarsiero BD, Johnson ME, Fung LW, J Biol Chem. 2010 May 7;285(19):14572-84. Epub 2010 Mar 14. PMID: 20228407

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