2NDB

NMR structure of omega-agatoxin IVA in DPC micelles

Summary for 2NDB

• Entry DOI: 10.2210/pdb2ndb/pdb
• NMR Information: BMRB: 26054
• Descriptor: Omega-agatoxin-Aa4a (1 entity in total)
• Functional Keywords: neurotoxin, toxin
• Biological source: Agelenopsis aperta (North American funnel-web spider)
• Cellular location: Secreted : P30288
• Total number of polymer chains: 1
• Total formula weight: 5277.44

Authors

Ryu, J.H.,Kim, J.I. (deposition date: 2016-05-12, release date: 2017-09-13, Last modification date: 2024-11-20)

Primary citation

Ryu, J.H.,Jung, H.J.,Konishi, S.,Kim, H.H.,Park, Z.Y.,Kim, J.I.
Structure-activity relationships of omega-Agatoxin IVA in lipid membranes
Biochem. Biophys. Res. Commun., 482:170-175, 2017

PubMed Abstract: To analyze structural features of ω-Aga IVA, a gating modifier toxin from spider venom, we here investigated the NMR solution structure of ω-Aga IVA within DPC micelles. Under those conditions, the Cys-rich central region of ω-Aga IVA still retains the inhibitor Cys knot motif with three short antiparallel β-strands seen in water. However, N HSQC spectra of ω-Aga IVA within micelles revealed that there are radical changes to the toxin's C-terminal tail and several loops upon binding to micelles. The C-terminal tail of ω-Aga IVA appears to assume a β-turn like conformation within micelles, though it is disordered in water. Whole-cell patch clamp studies with several ω-Aga IVA analogs indicate that both the hydrophobic C-terminal tail and an Arg patch in the core region of ω-Aga IVA are critical for Cav2.1 blockade. These results suggest that the membrane environment stabilizes the structure of the toxin, enabling it to act in a manner similar to other gating modifier toxins, though its mode of interaction with the membrane and the channel is unique.

PubMed: 27838299
DOI: 10.1016/j.bbrc.2016.11.025

Experimental method

SOLUTION NMR