Immunological identification and characterization of a delayed rectifier K+ channel polypeptide in rat brain.

Antibodies specific for the drk1 polypeptide were used to characterize the corresponding protein in rat brain. Recombinant and synthetic immunogens containing fragments of the drk1 polypeptide were produced. Antibodies raised to these immunogens display monospecific reactions with the same 130-kDa polypeptide on immunoblots of adult rat brain membranes. Immunoprecipitation of 125I-labeled brain membranes identifies a 38-kDa peptide in tight association with the drk1 polypeptide. Immunohistochemical staining of sections of adult rat cortex shows that drk1 protein is restricted to neurons, where staining is present on dendrites and cell bodies but not on axons. These studies point to the value of such immunological reagents to the further characterization of the components of this delayed rectifier K+ channel in the mammalian central nervous system.