ID TXM1_DENAN Reviewed; 66 AA. AC P81030; DT 01-NOV-1997, integrated into UniProtKB/Swiss-Prot. DT 01-NOV-1997, sequence version 1. DT 03-APR-2013, entry version 62. DE RecName: Full=Muscarinic toxin 1; DE Short=MT1; DE Short=MTx1; OS Dendroaspis angusticeps (Eastern green mamba) (Naja angusticeps). OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; OC Lepidosauria; Squamata; Scleroglossa; Serpentes; Colubroidea; OC Elapidae; Elapinae; Dendroaspis. OX NCBI_TaxID=8618; RN [1] RP PROTEIN SEQUENCE. RX PubMed=8154745; DOI=10.1111/j.1749-6632.1994.tb26623.x; RA Karlsson E., Jolkkonen M., Satyapan N., Adem A., Kumlin E., RA Hellman U., Wernstedt C.; RT "Protein toxins that bind to muscarinic acetylcholine receptors."; RL Ann. N. Y. Acad. Sci. 710:153-161(1994). RN [2] RP PROTEIN SEQUENCE. RX PubMed=7570626; DOI=10.1016/0041-0101(94)00102-E; RA Jolkkonen M., Adem A., Hellman U., Wernstedt C., Karlsson E.; RT "A snake toxin against muscarinic acetylcholine receptors: amino acid RT sequence, subtype specificity and effect on guinea-pig ileum."; RL Toxicon 33:399-410(1995). RN [3] RP FUNCTION. RX PubMed=7778123; DOI=10.1016/0041-0101(94)00161-Z; RA Kornisiuk E., Jerusalinsky D., Cervenansky C., Harvey A.L.; RT "Binding of muscarinic toxins MTx1 and MTx2 from the venom of the RT green mamba Dendroaspis angusticeps to cloned human muscarinic RT cholinoceptors."; RL Toxicon 33:11-18(1995). CC -!- FUNCTION: Binds irreversibly to M1 (CHRM1) muscarinic CC acetylcholine receptors, and reveals a slightly weaker effect at CC M3 (CHRM3) receptor. CC -!- SUBUNIT: Monomer (By similarity). CC -!- SUBCELLULAR LOCATION: Secreted. CC -!- TISSUE SPECIFICITY: Expressed by the venom gland. CC -!- MISCELLANEOUS: Has no effect on M2 (CHRM2) and M4 (CHRM4) CC receptors (PubMed:7778123). CC -!- SIMILARITY: Belongs to the snake three-finger toxin family. Type A CC muscarinic toxin subfamily. 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 PDB; 3FEV; X-ray; 1.30 A; A/B/C=1-16. DR PDB; 3NEQ; X-ray; 1.25 A; A/B=49-57. DR PDB; 4DO8; X-ray; 1.80 A; A/B=1-66. DR PDBsum; 3FEV; -. DR PDBsum; 3NEQ; -. DR PDBsum; 4DO8; -. DR ProteinModelPortal; P81030; -. DR SMR; P81030; 1-66. DR HOVERGEN; HBG006553; -. DR EvolutionaryTrace; P81030; -. DR GO; GO:0035792; C:other organism postsynaptic membrane; IEA:UniProtKB-KW. DR GO; GO:0030550; F:acetylcholine receptor inhibitor activity; IEA:UniProtKB-KW. DR GO; GO:0035821; P:modification of morphology or physiology of other organism; IEA:InterPro. DR InterPro; IPR003571; Snake_toxin. DR InterPro; IPR018354; Snake_toxin_BS. DR Pfam; PF00087; Toxin_1; 1. DR PROSITE; PS00272; SNAKE_TOXIN; 1. PE 1: Evidence at protein level; KW 3D-structure; Acetylcholine receptor inhibitor; KW Direct protein sequencing; Disulfide bond; Neurotoxin; KW Postsynaptic neurotoxin; Secreted; Toxin. FT CHAIN 1 66 Muscarinic toxin 1. FT /FTId=PRO_0000093641. FT DISULFID 3 24 By similarity. FT DISULFID 17 42 By similarity. FT DISULFID 46 58 By similarity. FT DISULFID 59 64 By similarity. FT STRAND 2 8 FT STRAND 11 16 FT STRAND 23 32 FT STRAND 35 45 FT STRAND 54 57 FT TURN 62 65 SQ SEQUENCE 66 AA; 7518 MW; EAAC074F4A00DD3E CRC64; LTCVTSKSIF GITTENCPDG QNLCFKKWYY IVPRYSDITW GCAATCPKPT NVRETIRCCE TDKCNE //