title: Isolation and characterization of a T-superfamily conotoxin from Conus litteratus with targeting tetrodotoxin-sensitive sodium channels.
abstract: A T-1-conotoxin, lt5d, was purified and characterized from the venom of vermivorous hunting cone snails Conus litteratus. The complete amino acid sequence of lt5d (DCCPAKLLCCNP) has been determined by Edman degradation. With two disulfide bonds, the calculated average mass is 1274.57 Da, which is confirmed by MALDI-TOF mass spectrometry (average mass 1274.8778). Under whole cell patch-clamp mode, lt5d inhibits tetrodotoxin-sensitive sodium currents on adult rat dorsal root ganglion neurons, but has no effects on tetrodotoxin-resistant sodium currents. The inhibition of TTX-sensitive sodium currents by lt5d was found to be concentration-dependent with the IC(50) value of 156.16 nM. Thus, this is the first T-superfamily conotoxin identified to block TTX-sensitive sodium channels.
authors.affiliation: State Key Laboratory of Biocontrol, The Open Laboratory for Marine Functional Genomics of the State High-Tech Development Program, Department of Biochemistry, College of Life Sciences, Sun Yat-Sen (Zhongshan) University, People's Republic of China.
authors.forename: Junliang
authors.initials: J
authors.lastname: Liu
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Wu
authors.forename: Canhui
authors.initials: C
authors.lastname: Pi
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Maojun
authors.initials: M
authors.lastname: Zhou
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Shangwu
authors.initials: S
authors.lastname: Chen
authors.forename: Anlong
authors.initials: A
authors.lastname: Xu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020916:Conotoxins / Q000235:genetics* / Q000302:isolation & purification* / Q000494:pharmacology; D052078:Conus Snail / Q000737:chemistry* / Q000235:genetics*; D008970:Molecular Weight; D010146:Pain / Q000188:drug therapy; D051381:Rats; D017207:Rats, Sprague-Dawley; D015222:Sodium Channels / Q000187:drug effects*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013779:Tetrodotoxin / Q000494:pharmacology
chemical_list: D020916:Conotoxins; D015222:Sodium Channels; D013779:Tetrodotoxin