ID SRTXB_ATRBI Reviewed; 21 AA. AC P80163; DT 01-APR-1993, integrated into UniProtKB/Swiss-Prot. DT 01-APR-1993, sequence version 1. DT 25-MAY-2022, entry version 70. DE RecName: Full=Bibrotoxin; DE Short=BTX; OS Atractaspis bibronii (Bibron's mole viper) (Southern stiletto snake). OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera; OC Serpentes; Colubroidea; Lamprophiidae; Atractaspidinae; Atractaspis. OX NCBI_TaxID=61304; RN [1] RP PROTEIN SEQUENCE, AND FUNCTION. RC TISSUE=Venom; RX PubMed=8416802; DOI=10.1016/0014-5793(93)81142-m; RA Becker A., Dowdle E.B., Hechler U., Kauser K., Donner P., Schleuning W.-D.; RT "Bibrotoxin, a novel member of the endothelin/sarafotoxin peptide family, RT from the venom of the burrowing asp Atractaspis bibroni."; RL FEBS Lett. 315:100-103(1993). CC -!- FUNCTION: Vasoconstrictor activity. These toxins cause cardiac arrest CC probably as a result of coronary vasospasm. May act by displaying CC agonistic activities towards endothelin-1 and -2 receptors (EDNRA and CC EDNRB). {ECO:0000269|PubMed:8416802}. CC -!- SUBCELLULAR LOCATION: Secreted. CC -!- TISSUE SPECIFICITY: Expressed by the venom gland. CC -!- SIMILARITY: Belongs to the endothelin/sarafotoxin family. CC {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR PIR; S27039; S27039. DR AlphaFoldDB; P80163; -. DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell. DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW. DR GO; GO:0019229; P:regulation of vasoconstriction; IEA:InterPro. DR GO; GO:0042310; P:vasoconstriction; IEA:UniProtKB-KW. DR InterPro; IPR019764; Endothelin_toxin_CS. DR InterPro; IPR001928; Endothln-like_toxin. DR Pfam; PF00322; Endothelin; 1. DR SMART; SM00272; END; 1. DR PROSITE; PS00270; ENDOTHELIN; 1. PE 1: Evidence at protein level; KW Cardiotoxin; Direct protein sequencing; Disulfide bond; KW G-protein coupled receptor impairing toxin; Secreted; Toxin; Vasoactive; KW Vasoconstrictor. FT PEPTIDE 1..21 FT /note="Bibrotoxin" FT /id="PRO_0000043645" FT SITE 21 FT /note="Endothelin-receptor binding site" FT /evidence="ECO:0000250" FT DISULFID 1..15 FT /evidence="ECO:0000250" FT DISULFID 3..11 FT /evidence="ECO:0000250" SQ SEQUENCE 21 AA; 2511 MW; 83A5DFB81D036AE2 CRC64; CSCADMTDKE CLYFCHQDVI W //