SO3 (P01540) Protein Card

General Information
Name SO3
Alternative name(s) SO-3
Organism Conus striatus (Striated cone)
Organism region Indo-Pacific
Organism diet piscivorous
Protein Type Wild type
Protein precursor SO3 precursor (1217)
SO3 precursor (864)
SO3 precursor (1216)
SO3 precursor (1219)
Notes Comparable inhibition of N-type Ca channel (Cav2.2) than MVIIA (Wen et al.). The replacement of MVIIA loop 2 by the loop 2 of SO-3 not only enhanced the peptide/Cav2.2 binding but also decreased its toxicity on goldfish, attenuated mouse tremor symptom, spontaneous locomotor activity, and coordinated locomotion function (Wang et al. 2016).

Classification
Conopeptide class conotoxin
Gene superfamily O1 superfamily
Cysteine framework VI/VII
Pharmacological family omega conotoxin

Sequence
CKAAGKPCSRIAYNCCTGSCRSGKC(nh2)
Modified residues
positionsymbolname
26nh2C-term amidation
Sequence evidence nucleic acid level
Average Mass 2560.99
Monoisotopic Mass 2559.08
Isoelectric Point 12.59
Extinction Coefficient [280nm] 1490.00

Activity

IC50: Voltage-Gated Calcium Channels

TargetOrganismIC50nhillRef
Cav2.2H. sapiens0.16 uM+/-0.031.16Wang,F. et al. (2016)

IC50: Voltage-Gated Sodium Channels

TargetOrganismIC50nhillRef
Nav TTX-RR. norvegicus>100uMWen,L. et al. (2005)

Percentage inhibition: Voltage-Gated Calcium Channels

TargetOrganism% inhibitionConcentrationRef
Cav2.1H. sapiens(Up to 10uM administered with no effect)0Wang,F. et al. (2016)

References
Lu,B.S., Yu,F., Zhao,D., Huang,P.T. and Huang,C.F. (1999) Conopeptides from Conus striatus and Conus textile by cDNA cloning Peptides 20:1139-1144
Dai,Q., Liu,F., Zhou,Y., Lu,B., Yu,F. and Huang,P. (2003) The synthesis of SO-3, a conopeptide with high analgesic activity derived from Conus striatus J. Nat. Prod. 66:1276-1279
Wen,L., Yang,S., Qiao,H., Liu,Z., Zhou,W., Zhang,Y. and Huang,P. (2005) SO-3, a new O-superfamily conopeptide derived from Conus striatus, selectively inhibits N-type calcium currents in cultured hippocampal neurons Br. J. Pharmacol. 145:728-739
Yan,Y., Tu,G., Luo,X., Dai,Q., Huang,P. and Zhang,R. (2003) Three-Dimensional Solution Structure Of W-Conotoxin So3 Determined By 1h Nmr Chin.Sci.Bull. 48:1097
Wang,F., Yan,Z., Liu,Z., Wang,S., Wu,Q., Yu,S., Ding,J. and Dai,Q. (2016) Molecular basis of toxicity of N-type calcium channel inhibitor MVIIA. Neuropharmacology 101:137-145

Internal links
Protein Precursor SO3 precursor (1217)
SO3 precursor (864)
SO3 precursor (1216)
SO3 precursor (1219)
Nucleic acids
Structure SOLUTION STRUCTURE OF OMEGA CONOTOXIN SO3 DETERMINED BY 1H- NMR

External links
Ncbi 1FYG_A

Tools