Fig. 8. Accumulation of isotope-labeled phenylalanine (A) and methionine (B) in deionized water-injected (empty circles and blue lines) and agNAT8 transcript-injected (black filled circles and red lines) oocytes. Values are means ± s.e.m. for at least three oocytes per data point. Lines are nonlinear regression fits of the data sets by a single rectangular function, f=a^*x/(b+x). (C) pH dependency of phenylalanine-induced currents mediated by agNAT8. Values are means ± s.e.m. for at least three oocytes/experiment per data point. Data from different oocytes were normalized in each group relative to values at pH 7.3. The straight line represents a linear regression of the entire data set, f=y₀+ax.