OsAKT2

• Symbol: OsAKT2
• MSU: LOC_Os05g35410
• RAPdb: Os05g0428700

• Rice shaker potassium channel OsKAT1 confers tolerance to salinity stress on yeast and rice cells, 2007, Plant Physiol.
• Phosphatidic acid directly binds with rice potassium channel OsAKT2 to inhibit its activity., 2020, Plant J.
• Multiple basic amino acid residues contribute to phosphatidic acid-mediated inhibition of rice potassium channel OsAKT2, 2020, Plant Signal Behav ..
• Rice shaker potassium channel OsAKT2 positively regulates salt tolerance and grain yield by mediating K + redistribution, 2021, Plant Cell Environ.
• The rectification control and physiological relevance of potassium channel OsAKT2., 2021, Plant Physiol.

Genbank accession number

• Disruption of OsAKT2 results in delayed growth of rice seedlings under short-day conditions
• Here, we identified the rice OsAKT2 as the ortholog of Arabidopsis AtAKT2, which is primarily expressed in the shoot phloem and localized at the plasma membrane
• Phosphatidic acid directly binds with rice potassium channel OsAKT2 to inhibit its activity.
• Multiple basic amino acid residues contribute to phosphatidic acid-mediated inhibition of rice potassium channel OsAKT2
• Here, using a PA biosensor (PAleon), we found that the exogenous PA treatment significantly increased the PA level at the plasma membrane of Xenopus oocytes which were used to express OsAKT2 for electrophysiological assays
• Rice shaker potassium channel OsAKT2 positively regulates salt tolerance and grain yield by mediating K + redistribution
• In addition, OsAKT2 also regulates the translocation of K+ and sucrose from old leaves to young leaves, and affects grain shape and yield
• Here, we provide physiological and genetic evidence of the involvement of phloem-localized OsAKT2 in rice salt tolerance
• Under salt stress, a T-DNA knock-out mutant, osakt2 and two CRISPR lines showed a more sensitive phenotype and higher Na+ accumulation than wild type
• Disruption of OsAKT2 decreases K+ concentration in phloem sap and inhibits shoot-to-root redistribution of K+
• Additionally, overexpression of OsAKT2 ameliorated the salt tolerance of Arabidopsis
• Overexpression of OsAKT2 complemented the K+ deficiency in the phloem sap and leaves of the mutant plants but did not significantly contribute to the transport of sugars
• However, the expression of OsAKT2-K191R overcame both the shortage of phloem K+ and sucrose of the akt2 mutant, which was comparable to the effects of the overexpression of AtAKT2, while the expression of the inward mutation AtAKT2-R195K resembled the effects of OsAKT2

• OsAKT2, OsCBL1, The rectification control and physiological relevance of potassium channel OsAKT2, OsAKT2 was modulated by OsCBL1/OsCIPK23, evoking the outward activity and diminishing the inward current.
• OsAKT2, OsCIPK23, The rectification control and physiological relevance of potassium channel OsAKT2, OsAKT2 was modulated by OsCBL1/OsCIPK23, evoking the outward activity and diminishing the inward current.