{"product_id":"calciseptine-bhp21300112","title":"Calciseptine","description":"\u003ch2\u003eOverview\u003c\/h2\u003e \u003cp\u003e\u003cstrong\u003eCalciseptine\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\u003eL-type Ca2+ channels\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 CAS: 178805-91-9, MW: 7036 Da, Formula: C299H468N90O87S10.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSource \/ origin:\u003c\/strong\u003e Dendroaspis polylepis polylepis (Black mamba).\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-Cys22, Cys17-Cys39, Cys41-Cys52 and Cys53-Cys58\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\u003eCalciseptine is a peptide toxin originally isolated from black mamba (Dendroaspis polylepsis) venom (1, 2). A three-finger toxin, calciseptine consists of 60 amino acids with 4 disulfide bridges (2). It is a specific L-type CaV channel blocker selective for CaV1.2 (3). Calciseptine binds to the shoulder of the CaV1.2 pore domain and traps the channel in a non-conductive conformation (4).Calciseptine blocks spontaneous or K+-induced contraction of cardiac and smooth muscle cells (2). However, in skeletal muscle, it increases L-type currents, modulating Ca2+ permeation (5). Using a patch clamp, calciseptine was shown to specifically block L-type CaV channel currents in neuronal cells in culture, with IC50 values of 15-500 nM (2). It was also shown to reduce the open probability and availability of the L-type channel in guinea pig portal vein smooth muscle cells, using outside-out patch clamping (6).CaV1.2 is one of 10 voltage-gated calcium channels (VGCCs), which are divided into three families based on the pore-forming α1 subunit (7); they were originally divided based on activation voltage current (8). Encoded by the CACNA1C gene, CaV1.2 consists of the three subunits α1, a2δ, and β. This channel is expressed by smooth and cardiac muscle, pancreas, neurons, and fibroblasts. It is involved in central nervous system function and neuroendocrine regulation, cardiac and smooth muscle contractibility, and multiple other physiological processes (9).\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":53073011343725,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7424\/7277\/files\/SPC-500_gr_655.gif?v=1772699876","url":"https:\/\/www.ebiohippo.com\/products\/calciseptine-bhp21300112","provider":"BioHippo","version":"1.0","type":"link"}