HAI1 — Arabidopsis thaliana

Summary

AT5G59220 (HAI1, also known as SAG113) encodes a protein phosphatase 2C (PP2C) family member with protein phosphatase regulator and inhibitor activities, as well as anion transporter and voltage-gated channel activities. In Arabidopsis, HAI1 is associated with abscisic acid (ABA) signaling, water homeostasis, chlorophyll breakdown, seed dormancy release, and responses to carbon dioxide, humidity, and water stress. The gene is linked to traits including leaf water potential, turgor pressure, stomatal regulation, water use efficiency, biomass production, photosynthetic rate, and sensitivities to alkali, magnesium, manganese, potassium, nitrogen, and nitrate. It localizes to the tonoplast, vacuole, ER membrane, and cis-Golgi network, and is connected to pathways in ABA biosynthesis and signaling, drought and salinity responses, and root hair development. Studies of related genes in other species link the family to ABA sensitivity, proline accumulation under low water potential, and S-type anion channel activation.