Mutation of the K transporter SlHAK5 of tomato alters pistil morphology, ionome, metabolome and transcriptome in flowers.

K accumulation in plant tissues is a crucial factor for plant growth and development. The tomato high-affinity K transporter SlHAK5 is essential for root K acquisition from low external concentrations. It is also involved in K accumulation in pollen and plant fertility as slhak5 KO plants show a low rate of pollen germination, impaired pollen tube growth and parthenocarpic fruits.

Increased tolerance to low K, and to cationic stress of Arabidopsis plants by expressing the F130S mutant version of the K transporter AtHAK5.

Potassium (K) selectivity of high-affinity K uptake systems is crucial for plant growth under low K and in the presence of inhibitors of K uptake that are toxic to plants such as Na or Cs. Here, we express a mutated version of the Arabidopsis AtHAK5 high-affinity K transporter consisting on a change of phenylalanine 130 to serine (F130S) in athak5 akt1 double mutant plants. F130S-expressing plants show better growth, increased K uptake from low external concentrations and higher K contents when grown at low K (10 μM) and when grown at low K in the presence of Na (15 mM) or Cs (1 μM).