{"product_id":"hstx1-r14a-bhp21300222","title":"HsTX1[R14A]","description":"\u003ch2\u003eOverview\u003c\/h2\u003e \u003cp\u003e\u003cstrong\u003eHsTX1[R14A]\u003c\/strong\u003e is a research-grade protein\/peptide reagent used in research settings. It is commonly applied as a tool reagent related to \u003cstrong\u003eKV1.3\u003c\/strong\u003e biology and\/or assay development. It is supplied in Lyophilized format to support flexible downstream use in RUO workflows. Researchers commonly pair it with applications such as Electrophysiology.\u003c\/p\u003e \u003ch2\u003eKey elements and design rationale\u003c\/h2\u003e \u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eMolecular identity:\u003c\/strong\u003e MW: 3733.4 Da, Formula: C146H239N51O46S9.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSource \/ origin:\u003c\/strong\u003e Heterometrus spinifer (Asia giant forest scorpion) (Malaysian black scorpion).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuality attributes:\u003c\/strong\u003e Purity: ≥98% (HPLC); Bioassay tested: Yes; Sterile \/ endotoxin-free: No.\u003c\/li\u003e \u003c\/ul\u003e \u003ch3\u003eModifications\u003c\/h3\u003e \u003cp\u003eDisulfide bonds between: Cys3-Cys24, Cys9-Cys29, Cys13-Cys31 and Cys19-Cys34 Cys34 = C-terminal amidation\u003c\/p\u003e \u003cp\u003eWhen used as a biochemical or pharmacological tool, results are best interpreted relative to the experimental system (species, expression level, and assay readout) and with appropriate negative and competition-style controls where relevant. This product is intended for research use only.\u003c\/p\u003e \u003ch2\u003eBiological background\u003c\/h2\u003e \u003cp\u003eHsTX1[R14A] is an analogue of HsTX1, a 34-residue peptide toxin originally derived from the venom of the scorpion Heterometrus spinifer1,2. In this analogue, arginine at position 14 is substituted with alanine, resulting in a potent and selective blocker of voltage-gated potassium channels (KV1.3), with an IC50 of 45 ± 3 pM. HsTX1[R14A] exhibits more than 2,000-fold selectivity for KV1.3 over KV1.11. The HsTX1[R14A] toxin has been shown to be highly resistant to proteolysis and stable in plasma1. This resistance, stabilized by four disulfide bridges, is superior to that of ShK analogues, including the clinical candidate ShK-186, which contains only three disulfide bridges3. Pharmacokinetic studies indicate that both intravenous and subcutaneous applications are viable for the delivery of this potent peptide4. Additionally, HsTX1[R14A] has shown efficacy in a model of rheumatoid arthritis, suggesting its potential as a therapeutic agent for effector memory T cells (TEM) cell-mediated autoimmune diseases5. Its high stability and bioavailability make HsTX1[R14A] toxin an excellent candidate for further development as a therapeutic lead and as a probe for therapeutic applications6. KV1.3 upregulation is implicated in various autoimmune and neuroinflammatory diseases, including rheumatoid arthritis, psoriasis, multiple sclerosis, and type I diabetes. While the therapeutic potential of KV1.3 blockade has been well-characterized in autoimmune diseases driven by effector memory T cells, emerging evidence suggests that KV1.3 also plays a role in diseases involving T helper cells, macrophages, microglia, and class-switched B cells3. This expanded understanding of KV1.3's role in various cell types and diseases further highlights the potential therapeutic value of HsTX1[R14A] and similar KV1.3 blockers.\u003c\/p\u003e \u003ch2\u003eResearch relevance and current trends\u003c\/h2\u003e \u003cul\u003e \u003cli\u003eUsing high-specificity ligands, toxins, and engineered peptides to dissect closely related receptor\/channel subtypes and signaling microdomains.\u003c\/li\u003e\n\u003cli\u003ePairing labeled (e.g., fluorescent) proteins\/peptides with advanced imaging to map surface expression, trafficking, and nanoscale organization.\u003c\/li\u003e\n\u003cli\u003eIncreasing emphasis on reproducibility through standardized characterization (identity, purity, and lot QC) and transparent reporting of reagent attributes.\u003c\/li\u003e \u003c\/ul\u003e \u003ch2\u003eCommon research applications\u003c\/h2\u003e \u003cul\u003e \u003cli\u003eElectrophysiology: commonly used to compare signal, binding, or functional readouts across conditions without implying a specific protocol.\u003c\/li\u003e \u003c\/ul\u003e \u003cp\u003eAcross these use cases, changes in signal or functional readout are generally interpreted as evidence of differences in target abundance, accessibility, or engagement, but alternative explanations (matrix effects, off-target interactions, or assay artifacts) should be considered.\u003c\/p\u003e \u003ch2\u003eNotes for experimental interpretation\u003c\/h2\u003e \u003cul\u003e \u003cli\u003eAssay context matters: binding assays, functional modulation, and detection workflows can yield different readouts even for the same target system.\u003c\/li\u003e\n\u003cli\u003eTarget complexity: closely related family members, splice variants, and post-translational modifications can influence apparent specificity and potency.\u003c\/li\u003e\n\u003cli\u003eMatrix and sample effects: buffer composition, detergents, and biological matrices may alter stability or apparent activity; interpret with appropriate controls.\u003c\/li\u003e\n\u003cli\u003eControl concepts: include negative controls and orthogonal validation (e.g., genetic perturbation or alternative reagents) to support robust interpretation.\u003c\/li\u003e \u003c\/ul\u003e \u003c!-- Sources (internal): - UniProt Knowledgebase (UniProtKB) — UniProt Consortium — https:\/\/www.uniprot.org\/ - NCBI Gene — National Center for Biotechnology Information (NCBI) — https:\/\/www.ncbi.nlm.nih.gov\/gene\/ - NCBI Protein — National Center for Biotechnology Information (NCBI) — https:\/\/www.ncbi.nlm.nih.gov\/protein\/ - PubChem — NIH\/NLM\/NCBI — https:\/\/pubchem.ncbi.nlm.nih.gov\/ - IUPHAR\/BPS Guide to Pharmacology — IUPHAR\/BPS — https:\/\/www.guidetopharmacology.org\/ - RCSB Protein Data Bank (PDB) — RCSB PDB — https:\/\/www.rcsb.org\/ - NCBI Bookshelf — NIH\/NLM — https:\/\/www.ncbi.nlm.nih.gov\/books\/ --\u003e","brand":"Alomone Labs","offers":[{"title":"Default Title","offer_id":53073019634029,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7424\/7277\/files\/STH-310-HsTxR14A-0.5nM-on-Kv1.3-in-oocytes_811.jpg?v=1772699890","url":"https:\/\/www.ebiohippo.com\/products\/hstx1-r14a-bhp21300222","provider":"BioHippo","version":"1.0","type":"link"}