- GST fusion protein with the sequence TLSKSEYMVIEEGGMNHSAFPQTPFKTGNSTATCTTNNNPNSCVNIKKIFTDV, corresponding to amino acid residues 523-575 of human KV1.3 (Accession P22001). Intracellular, C-terminus.
- Transfected HEK-293 cell lysate (Vicente, R. et al. (2006) J. Biol. Chem. 281, 37675.).
- Rat brain sections.
- Rat neural progenitor cells (NPCs) (1:200) (Liebau, S. et al. (2006) J. Neurochem. 99, 426.).
KV1.3 belongs to the Shaker family of voltage-dependent K+ channels. The channel, encoded by KCNA3, is widely expressed in the brain, lung and osteoclasts and in several cell populations of hematopoietic origin. The prominence of KV1.3 channels in these cells (particularly in T lymphocytes) directed much research attention. It was found that KV1.3 is the main channel responsible for maintaining the resting potential in quiescent cells and regulating the Ca2+ signaling that is indispensable for normal T lymphocyte activation.1,2 Based on the central role of KV1.3 in regulating the initiation of an immune response, the channel has been recognized as a potential target for immunosuppressant drugs.1
KV1.3 channels are potently inhibited by several venomous peptide toxins among them Charybdotoxin (2.6 nM), Noxiustoxin (1 nM), Kaliotoxin (0.65 nM), Margatoxin (0.05 nM), Agitoxin-1 (1.7 nM), Agitoxin-2 (0.004 nM), Hongotoxin-1 (0.09 nM) and Stichodactyla toxin (0.01 nM).3-7