part_of part of part of has_part has part has part plasma membrane external side of plasma membrane GO:0009897 The leaflet of the plasma membrane that faces away from the cytoplasm and any proteins embedded or anchored in it or attached to its surface. cellular_component external leaflet of plasma membrane juxtamembrane outer surface of cytoplasmic membrane cell surface side of membrane MS4A1 CD40LG CD79A FCER1A MS4A2 FCGR3A IGKC IL7R ITGAX KIT MCAM NCAM1 PECAM1 SCNN1G VCAM1 EMCN