Isoform 4 of Potassium voltage-gated channel subfamily KQT member 2

KCNQ2 encodes a voltage-gated potassium channel protein belonging to the KQT subfamily, which functions in regulating cellular electrical excitability through potassium ion conductance (UniProt: O43526-4). These channels are widely expressed in neuronal tissues and play critical roles in controlling action potential propagation and neuronal excitability. KCNQ2 mutations are associated with neonatal epilepsy and other neurological conditions affecting ion channel function.

In Alzheimer's Disease, isoform 4 of KCNQ2 shows a consistent downregulation pattern (Chaparral AD proteomics). According to post-mortem analysis of AD brain tissue compared to age-matched controls using TMT-labeled quantitative proteomics across four subcellular fractions, KCNQ2 isoform 4 was significantly reduced with a mean log2 fold-change of −0.41. This downregulation may reflect altered neuronal electrophysiology and ion channel dysfunction in the AD brain, potentially contributing to the cognitive and synaptic deficits observed in the disease.