Figure 5
Differential localization of sea bream Aqp1a and Aqp1b expressed in X. laevis oocytes. (A) Pf of oocytes expressing increasing amounts of Aqp1a or Aqp1b cRNA. Values represent the mean ± SEM (n = 6–10 oocytes) from 3 independent experiments. (B) Immunoblots of total and plasma membrane equivalents (TM and PM, respectively) of oocytes expressing 1 ng of Aqp1a or Aqp1b. The arrows indicate two very close Aqp1b reactive bands. (C-E) Immunofluoresence microscopy of water-injected and Aqp1a- or Aqp1b-expressing oocytes. Arrows show localization of the protein at the plasma membrane. The arrowhead indicates Aqp1b in the cytoplasm below the plasma membrane. Bar, 50 μm. (F) Immunoblot of total membrane fraction of Aqp1b-expressing oocytes incubated with or without alkaline phosphatase (AP) for 6 h. In B and F, the apparent molecular mass of a 29-kDa marker is indicated on the left and right, respectively.