1. Pharmacological Profile of
Stichodactyla Helianthus (ShK)
Binding Affinity Color Key
200 pM <
200 – 1000 pM
1000 – 10 000 pM
10 000 – 100 000 pM
< 100 000 pM
Channel Binding
Color
Binding Affinity Specie of
Channel
Cell Type Reference
Kv1.1 16 +/- 3 pM Mouse (2)
0.6 pM, 16 pM, 28 pM (5)
29 +/- 3 pM L929 stable expressing channel (6)
Kv1.2 9000 +/- 300 pM Rat (2)
Kv1.3 11 +/- 1.4 pM Mouse (2)
60 +/- 40 pM (4)
133 pM Jurkat T-Lymphocytes (1)
50 pM (4)
1.4 pM, 10 pM, 11 pM, 132 pM (5)
13 +/- 4 pM L929 stable expressing channel (6)
16 pM (7)
Kv1.4 312 +/- 51 pM Mouse (2)
Kv1.5 > 100 000 pM Human (2)
Kv1.6 165 +/- 3 pM Human (2)
Kv1.7 11 500 +/- 2340 pM Human (2)
13 000 pM, 11 500 pM (5)
Kv3.1 > 100 000 pM Mouse (2)
> 100 000 pM (4)
Kv3.2 6 000 pM (5)
300 pM hKv3.2b Xenopus Oocytes (3)
Kv3.4 > 100 000 pM Mouse (2)
KCa4 28 000 +/- 3 300 pM Human (2)
IKCal 172 000 pM (7)

2. References
(1) M. W. Pennington, V. M. Mahnir, D. S. Krafte, I. Zaydenberg, M. E. Byrnes, I. Khaytin, K. Crowley, and W. R. Kem
(1996) Identification of Three Separate Binding Sites on SHK Toxin, a Potent Inhibitor of Voltage-Dependent Potassium
Channels in Human T-Lymphocytes and Rat Brain. Biochemical and Biophysical Research Communications 219:696-
701
(2) Katalin Kalman, Michael W. Pennington, Mark D. Lanigan, Angela Nguyen, Heiko Rauer, Vladimir Mahnir, Kathy
Paschetto, William R. Kem, Stephan Grissmer, George A. Gutman, Edward P. Christian, Michael D. Cahalan, Raymond
S. Norton, and K. George Chand (1998) ShK-Dap22, a Potent Kv1.3-specific Immunosuppressive Polypeptide. The J. of
Biological Chem, Vol 273 No. 49:32697–32707
(3) Lizhen Yan, James Herrington, Ethan Goldberg, Paula M. Dulski, Randal M. Bugianesi, Robert S. Slaughter, Priya
Banerjee, Richard M. Brochu, Birgit T. Priest, Gregory J. Kaczorowski, Bernardo Rudy, and Maria L. Garcia (2005)
ShK, a Pharmacological Tool for Studying Kv3.2 Channels. Molecular Pharmacology Fast Forward, 67(5):1513-21
(4) Jayashree Aiyar (1999) Potassium channels in leukocytes and toxins that block them: Structure, function and therapeutic
implications. Perspectives in Drug Discovery and Design, 15/16: 257–280
(5) Susan I.V. Judge, Christopher T. Bever Jr. (2006) Potassium channel blockers in multiple sclerosis: Neuronal Kv channels
and effects of symptomatic treatment. Pharmacology & Therapeutics, 111:224 – 259
(6) Christine Beeton, Brian J. Smith, Jennifer K. Sabo, George Crossley, Daniel Nugent, Ilya Khaytin, Victor Chi, K. George
Chandy, Michael W. Pennington, and Raymond S. Norton (2007) The D-Diastereomer of ShK Toxin Selectively Blocks
Voltage-gated K Channels and Inhibits T Lymphocyte Proliferation. The J. of Biological Chem, Vol. 283, No. 2, pp. 988
–997
(7) K. George Chandy, Michael Cahalan, Michael Pennington, Raymond S. Norton, Heike Wulff and George A. Gutman
(2001) Potassium channels in T lymphocytes: toxins to therapeutic immunosuppressants. Toxicon, 39: 1269-1276