Figure 1: a) Side view of the aquaporin-1 monomer (accession code 1FQY) with trans-membrane helices H1, H2, H3, H4, H5 and H6, non-membrane-crossing helices HE and HB and loops LA, LB and LE labeled. b) End-on view of the aquaporin-1 monomer (accession code 1FQY) from the extracellular surface. The location of the aqueous pore can be seen running through the middle of the monomer. c) End-on view of the aquaporin-1 tetramer (accession code 2B5F) from the extracellular surface.