KEA5 Antibody

Overview of KEA5 Protein

KEA5 is a K⁺/H⁺ antiporter localized in endosomal compartments (Golgi, trans-Golgi network, and prevacuolar compartments) in Arabidopsis thaliana . It belongs to a six-member family (KEA1–KEA6) with distinct subcellular localizations and roles in ion transport.

Functional Role in pH and Ion Regulation

KEA5 works coordinately with KEA4 and KEA6 to:

• Maintain luminal pH in endomembranes (optimal range: pH 6.0–6.5) .

• Counteract acidification by exchanging luminal K⁺ for cytosolic H⁺ .

• Facilitate salt tolerance by regulating Na⁺ and K⁺ fluxes under stress .

Key findings:

• kea4 kea5 kea6 triple mutants exhibit acidic endosomal pH (~0.5–1.0 unit lower) and hypersensitivity to Na⁺/Li⁺ .

• KEA5’s activity is critical for balancing ion homeostasis independently of vacuolar NHX antiporters .

Transport Mechanism

KEA5 demonstrates bidirectional K⁺ transport in heterologous systems (E. coli), distinguishing it from KEA1–KEA3, which show unidirectional activity .

Data from

Genetic and Biochemical Insights

• Structure: KEA5 lacks the conserved DD motif in transmembrane domain 5, instead featuring a glutamine/asparagine residue that enhances K⁺ selectivity .

• Mutant Studies:

  • Disruption of KEA5 reduces growth under low K⁺ or high Na⁺ conditions .

  • Overexpression of KEA5 fails to rescue E. coli mutants deficient in K⁺ transporters, suggesting specialized regulatory mechanisms .

Antibody Applications in KEA5 Research

While no studies explicitly detail KEA5-specific antibodies, their inferred applications include:

• Localization assays (e.g., immunogold labeling to confirm endosomal targeting).

• Western blotting to quantify KEA5 expression under stress conditions.

• Mutant validation (e.g., verifying protein absence in kea5 knockouts).

Clinical and Agricultural Implications

Though KEA5 is not directly linked to human disease, its functional analogs in crops could inform strategies for:

• Engineering salt-tolerant plants.

• Optimizing nutrient transport in acidic soils.