5WJF:
reference: Crystal structure of murine 4-1BB and its interaction with 4-1BBL support a role for galectin-9 in 4-1BB signaling., Bitra A, Doukov T, Wang J, Picarda G, Benedict CA, Croft M, Zajonc DM, J Biol Chem. 2018 Jan 26;293(4):1317-1329. doi: 10.1074/jbc.M117.814905. Epub, 2017 Dec 14. PMID: 29242193

This OCA Structure page
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