3PO8:
reference: Structural and functional analysis of phosphothreonine-dependent FHA domain interactions., Pennell S, Westcott S, Ortiz-Lombardia M, Patel D, Li J, Nott TJ, Mohammed D, Buxton RS, Yaffe MB, Verma C, Smerdon SJ, Structure. 2010 Dec 8;18(12):1587-95. PMID: 21134638

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