Passive Transport of Water out of Cells by Aquaporins Aquaporin-0 (AQP0, also known as MIP), AQP1, AQP2, AQP3, AQP4, AQP5, AQP7, AQP8, AQP9, and AQP10 are 6-pass transmembrane proteins that passively transport water across the plasma membrane according to the concentration gradient. Each molecule contains a water channel and subunits assemble into homotetramers. In principle water can move in either direction through an aquaporin, however in vivo flow may occur in only one direction. Conductance of water by AQP0 is very low relative to other aquaporins. Authored: May, B, 2010-02-09 Edited: May, B, 2010-02-09 Pubmed10510269 Pubmed10564231 Pubmed11001937 Pubmed11027599 Pubmed11034202 Pubmed11076974 Pubmed11231887 Pubmed11532455 Pubmed11573934 Pubmed11952783 Pubmed12084581 Pubmed12801959 Pubmed1373524 Pubmed14514735 Pubmed14592814 Pubmed14701836 Pubmed1510932 Pubmed15703994 Pubmed15948717 Pubmed16325777 Pubmed16596446 Pubmed17178220 Pubmed17374283 Pubmed17920625 Pubmed18202181 Pubmed18501347 Pubmed18511455 Pubmed18555844 Pubmed18678926 Pubmed18762715 Pubmed18768791 Pubmed18948439 Pubmed19144687 Pubmed19170255 Pubmed19383790 Pubmed19590626 Pubmed19857466 Pubmed20147624 Pubmed3049610 Pubmed7510718 Pubmed7530250 Pubmed7535000 Pubmed7678419 Pubmed8140421 Pubmed8621489 Pubmed8855281 Pubmed9369468 Pubmed9405233 Pubmed9806845 Pubmed9829975 Reactome Database ID Release 43507870 Reactome, http://www.reactome.org ReactomeREACT_23851 Reviewed: Beitz, E, 2010-06-24 Reviewed: Calamita, G, 2010-07-15 Reviewed: Mathai, JC, MacIver, B, 2010-07-31