4PGZ:
reference: The strength and cooperativity of KIT ectodomain contacts determine normal ligand-dependent stimulation or oncogenic activation in cancer., Reshetnyak AV, Opatowsky Y, Boggon TJ, Folta-Stogniew E, Tome F, Lax I, Schlessinger J, Mol Cell. 2015 Jan 8;57(1):191-201. doi: 10.1016/j.molcel.2014.11.021. Epub 2014 , Dec 24. PMID: 25544564

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