title: Screening and cDNA cloning of Kv1 potassium channel toxins in sea anemones.
abstract: When 21 species of sea anemones were screened for Kv1 potassium channel toxins by competitive inhibition of the binding of (125)I-α-dendrotoxin to rat synaptosomal membranes, 11 species (two species of Actiniidae, one species of Hormathiidae, five species of Stichodactylidae and three species of Thalassianthidae) were found to be positive. Furthermore, full-length cDNAs encoding type 1 potassium channel toxins from three species of Stichodactylidae and three species of Thalassianthidae were cloned by a combination of RT-PCR, 3'RACE and 5'RACE. The precursors of these six toxins are commonly composed of signal peptide, propart and mature peptide portions. As for the mature peptide (35 amino acid residues), the six toxins share more than 90% sequence identities with one another and with κ(1.3)-SHTX-She1a (Shk) from Stichodactyla helianthus but only 34-63% identities with the other type 1 potassium channel toxins.
authors.affiliation: Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Konan-4, Minato-ku, Tokyo, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Honma
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nagashima
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shiomi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004353:Drug Evaluation, Preclinical; D004546:Elapid Venoms / Q000378:metabolism; D008387:Marine Toxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009498:Neurotoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D009792:Oceans and Seas; D026902:Potassium Channel Blockers / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D012615:Sea Anemones / Q000737:chemistry* / Q000235:genetics; D051637:Shaker Superfamily of Potassium Channels / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; D004546:Elapid Venoms; D008387:Marine Toxins; D009498:Neurotoxins; D026902:Potassium Channel Blockers; D051637:Shaker Superfamily of Potassium Channels; C020273:dendrotoxin