Stable association of Src-family PTK Fyn with Kv1.2/Kv1.5- and
Kv1.4/Kv1.5-containing heteromultimeric potassium channels in
mammalian hippocampus. (a) Kv1.5 subunits coassemble
with Kv1.2 and Kv1.4 subunits in hippocampus. Heteromultimeric Kv
channels were isolated from detergent solubilized rabbit hippocampus
synaptic membranes by immunoprecipitation (IP) with α−Kv1.2,
α−Kv1.4, or α−Kv1.5 antisera, using preimmune serum as a negative
control. IP samples were probed on Western blots with α−Kv1.2 mAb
(Upper, n = 6) or Kv1.4 mAb
(Lower, n = 6). (b)
Kv1.5 subunits that coimmunoprecipitate with Kv1.2 subunits are
detected by probing α−Kv1.2 mAb IPs with α−Kv1.5 antiserum
(n = 4), using α−CP mAb as a negative control.
(c) Fyn associates with Kv1.2- and Kv1.4-containing
channels in hippocampus. α−Fyn pAb IPs were probed with α−Kv1.2
mAb (Upper, n = 6), α−Kv1.4 mAb
(Middle, n = 4), or α−Fyn mAb
(Lower, n = 6). The negative control
IP antibody used was prepared by complete preabsorption of α−Fyn pAb
with an excess of the peptide antigen (PreAbs). (d) Fyn
associates with Kv1.5-containing channels in hippocampus. Fyn that
coimmunoprecipitates with Kv1.5 is detected by probing α−Kv1.5 IPs
with α−Fyn mAb (n = 3), using preimmune serum as
a negative control.