{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T22:16:57Z","timestamp":1792793817969,"version":"4.5.0"},"reference-count":38,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T00:00:00Z","timestamp":1754870400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"SPIRITS 2021 and ISHIZUE 2024 of Kyoto University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Scorpion venom contains various insecticidal peptides. Previously, through transcriptome analysis of the venom gland of Liocheles australasiae, we identified precursor sequences of several peptides that share sequences similar to those acting on K+ channels. In this study, we chemically synthesized five of the peptides which were found in the venom and evaluated their insecticidal activity against crickets. This revealed that one of the peptides, named LaIT6, exhibited significant insecticidal activity without mammalian toxicity. To identify amino acid residues important for the insecticidal activity of LaIT6, nine analogs were synthesized mainly by substituting acidic, basic, and aromatic residues with alanine. This revealed that two basic residues and an aromatic residue in the C-terminal region are important for the activity. This characteristic of structure-activity relationships, known as a functional dyad, is commonly observed in peptides that act on K+ channels, suggesting that the action target of LaIT6 is K+ channels. As expected, LaIT6 showed significant inhibitory activity against insect K+ channels. Since no activity against human K+ channels was observed, we concluded that the selectivity of LaIT6 is determined by differences in the action on K+ channels between insects and mammals.<\/jats:p>","DOI":"10.3390\/molecules30163346","type":"journal-article","created":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T17:22:07Z","timestamp":1754932927000},"page":"3346","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["LaIT6: A Novel Insect-Selective K+-Channel Toxin from Liocheles australasiae Scorpion Venom"],"prefix":"10.3390","volume":"30","author":[{"given":"Konoka","family":"Kumagai","sequence":"first","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takumi","family":"Kishimoto","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kathleen","family":"Carleer","sequence":"additional","affiliation":[{"name":"Toxicology and Pharmacology, University of Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nana","family":"Butatsu","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tsubasa","family":"Teramoto","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoya","family":"Mitani","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1778-6022","authenticated-orcid":false,"given":"Jan","family":"Tytgat","sequence":"additional","affiliation":[{"name":"Toxicology and Pharmacology, University of Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6931-8530","authenticated-orcid":false,"given":"Yoshiaki","family":"Nakagawa","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7050-5555","authenticated-orcid":false,"given":"Masahiro","family":"Miyashita","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1080\/15569543.2018.1530681","article-title":"Nature and applications of scorpion venom: An overview","volume":"39","author":"Tobassum","year":"2020","journal-title":"Toxin Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1007\/s12600-024-01201-2","article-title":"Scorpion venom insectotoxins: A sustainable alternative for pest control in agriculture","volume":"52","year":"2024","journal-title":"Phytoparasitica"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e20210026","DOI":"10.1590\/1678-9199-jvatitd-2021-0026","article-title":"Pain-related toxins in scorpion and spider venoms: A face to face with ion channels","volume":"27","author":"Diochot","year":"2021","journal-title":"J. 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