MrIC (P06003) Protein Card

General Information
Name MrIC
Alternative name(s) Mr1.7c,Mr1.8c
Organism Conus marmoreus
Organism region Indo-Pacific
Organism diet molluscivorous
Protein Type Wild type
Protein precursor Mr1.8 precursor (4571)
Notes This conotoxin is a co-agonist for nAChR. It is temporarily classified as an alpha-conotoxin but its classification should be changed (alpha-conotoxins are antagonists by definition).

Jin et al. 2014 stated that this peptide is coming from a precursor named Mr1.7 but the precursor they described was published under the name Mr1.8 by Liu et al 2012. Liu et al 2012 also published a peptide precursor Mr1.7 which is related but not identical to Mr1.8.

Mueller et al 2015 characterised the pharmacological activity and demonstrated that MrIC exclusively activates alpha-7 nAChR if modulated by type II allosteric modulators including PNU12059, TQS and SB-206553.


Classification
Conopeptide class conotoxin
Gene superfamily A superfamily
Cysteine framework I
Pharmacological family alpha conotoxin

Sequence
PECCTHPACHVSNPELC(nh2)
Modified residues
positionsymbolname
18nh2C-term amidation
Average Mass 1835.07
Monoisotopic Mass 1833.71
Isoelectric Point 5.63
Extinction Coefficient [280nm] NA

Activity

EC50: Nicotinic acetylcholine receptors

TargetOrganismEC50Ref
α7C. marmoreus(SB-206553 (150 uM))1.62 uMMueller,A. et al. (2015)
(Galantamine (10 uM))No responseMueller,A. et al. (2015)
(TQS (30 uM))47.8 uMMueller,A. et al. (2015)
(PNU120596 (25 uM))42.6 uMMueller,A. et al. (2015)
(PNU120596 (10 uM))1.9 uM+/-0.7Mueller,A. et al. (2015)
(PNU120596 (25 uM))63.1 uMMueller,A. et al. (2015)

References
Jin,A.H., Vetter,I., Dutertre,S., Abraham,N., Emidio,N.B., Inserra,M., Murali,S.S., Christie,M.J., Alewood,P.F. and Lewis,R.J. (2014) MrIC, a Novel α-Conotoxin Agonist in the Presence of PNU at Endogenous α7 Nicotinic Acetylcholine Receptors. Biochemistry 53:1-3
Mueller,A., Starobova,H., Inserra,M.C., Jin,A.H., Deuis,J.R., Dutertre,S., Lewis,R.J., Alewood,P.F., Daly,N.L. and Vetter,I. (2015) α-Conotoxin MrIC is a biased agonist at α7 nicotinic acetylcholine receptors. Biochem. Pharmacol. 94:155-163

Internal links
Protein Precursor Mr1.8 precursor (4571)
Nucleic acids
Structure

External links

Tools