Tamulustoxin: a novel potassium channel blocker from the venom of the Indian red scorpion Mesobuthus tamulus.
We have characterized tamulustoxin, a novel 35-amino-acid peptide found in the venom of the Indian red scorpion (Mesobuthus tamulus). Tamulustoxin was identified through a [125I]toxin I screen, designed to identify toxins that block voltage-activated potassium channels. Tamulustoxin has also been cloned by RT-PCR, using RNA extracted from scorpion venom glands. Tamulustoxin shares no homology with other scorpion venom toxins, although the positions of its six cysteine residues would suggest that it shares the same structural scaffold. Tamulustoxin rapidly inhibited both peak and steady-state currents (18.9 +/- 1.0 and 37 +/- 1.1%, respectively) produced by injecting CHO cells with mRNA encoding the hKv1.6 channel.
Strong
P N
PN
Sheffield Hallam University, UK. p.strong@shu.ac.uk
Clark
G S
GS
Armugam
A
A
De-Allie
F A
FA
Joseph
J S
JS
Yemul
V
V
Deshpande
J M
JM
Kamat
R
R
Gadre
S V
SV
Gopalakrishnakone
P
P
Kini
R M
RM
Owen
D G
DG
Jeyaseelan
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism*; D002847:Chromatography, Agarose; D003001:Cloning, Molecular; D006224:Cricetinae; D003545:Cysteine / Q000737:chemistry; D018076:DNA, Complementary / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D008969:Molecular Sequence Data; D018408:Patch-Clamp Techniques; D010455:Peptides / Q000494:pharmacology*; D026902:Potassium Channel Blockers; D015221:Potassium Channels / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012604:Scorpion Venoms / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology*; D012605:Scorpions; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D010455:Peptides; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D012333:RNA, Messenger; D012604:Scorpion Venoms; C428429:tamulustoxin protein, Mesobuthus tamulus; D012313:RNA; D003545:Cysteine; D002118:Calcium