Fig. 1.

BIB expression does not confer osmotically induced swelling in Xenopus oocytes. A, Osmotic water permeability was analyzed with a swelling assay (see Materials and Methods). Oocytes expressing human aquaporin-1 (circles; n = 5) or HABIB (squares; n = 4) and control (ctrl) oocytes (triangles;n = 4) were exposed to hypotonic saline at time 0, and the relative volume change with time was measured from the video-imaged cross-sectional area. Data are mean ± SD from a representative experiment; n = 4 or 5 oocytes per group.