Tyr13 is essential for the binding of omega-conotoxin MVIIC to the P/Q-type calcium channel.
An analog of omega-conotoxin MVIIC (Y13A-MVIIC) was synthesized by replacing Tyr13 with Ala to study the role of Tyr13 residue conserved in many omega-conotoxins. Y13A-MVIIC has an overall conformation similar to that of the native toxin, but an enormously reduced ability to displace 125I-omega-conotoxin MVIIC binding to rat cerebellar P2 membranes. These results suggest that Tyr13 is essential for the activity of omega-conotoxins at P/Q-type calcium channels.
Kim
J I
JI
Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan.
Takahashi
M
M
Martin-Moutot
N
N
Seagar
M J
MJ
Ohtake
A
A
Sato
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D002121:Calcium Channel Blockers / Q000737:chemistry* / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002531:Cerebellum / Q000378:metabolism; D017124:Conserved Sequence; D004220:Disulfides / Q000032:analysis; D007700:Kinetics; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology; D011487:Protein Conformation; D011689:Purkinje Cells / Q000378:metabolism; D051381:Rats; D017386:Sequence Homology, Amino Acid; D014443:Tyrosine; D020960:omega-Conotoxins
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D004220:Disulfides; D010455:Peptides; D020960:omega-Conotoxins; C075851:omega-conotoxin-MVIIC; D014443:Tyrosine