4KFW:
reference: Structural insight into Golgi membrane stacking by GRASP65 and GRASP55 proteins., Feng Y, Yu W, Li X, Lin S, Zhou Y, Hu J, Liu X, J Biol Chem. 2013 Sep 27;288(39):28418-27. doi: 10.1074/jbc.M113.478024. Epub, 2013 Aug 12. PMID: 23940043

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