Disruption of the disulfide bridge partially loses L-arginine transport function of SNAT4.

<p>cRNA of the wild type, C18A, C232A, C345A or C321A mutant was injected into <i>Xenopus</i> oocytes and subjected to [³H] L-arginine uptake assays. Water injected oocytes were used as a negative control. Data is presented as mean ± SEM, n = 3 (∼10 oocytes/sample). Mutants versus WT, *, P<0.05.