Synthesis and trafficking of the tonoplast potassium channel AtTPK1
Sorting signals of tonoplast proteins and the pathway they follow through the endomembrane system are still poorly characterized. Using Brefeldin A (an inhibitor of the Golgi-mediated traffic) we showed that a Golgi-dependent pathway for tonoplast delivery may exist. Then we generated various chimeric TPK1-TPK4 fusions, exchanging various domains. We observed that the cytosolic, C-terminal domain of TPK1 is sufficient to re-direct the plasma membrane TPK4 to the tonoplast.