Figure 5.

OPT3 Mediates Cation Uptake in X. laevis Oocytes.

Uptake of Fe²⁺ (A) and Cd²⁺ (B) in OPT3-expressing oocytes (OPT3) or water-injected cells (Control) at different time points. The basal uptake solution supplemented with 0.4 mM FeSO₄ + 1 mM l-ascorbic acid (A) or 0.5 mM CdCl₂ (B), yielded free extracellular ionic activities of 35 and 150 μM of {Cd²⁺}_out and {Fe²⁺}_out, respectively, as determined by GEOCHEM-EZ (Shaff et al., 2010). The dashed line in (A) indicates the basal concentration of endogenous Fe²⁺. Error bars represent se (n = 5). Asterisks indicate statistically significant differences (P ≤ 0.05).