Extended Data Figure 3: Negative-stain EM of TRPV1.
From: Structure of the TRPV1 ion channel determined by electron cryo-microscopy
a, Representative negative-stain image of purified minimal TRPV1 protein in detergent (n-dodecyl β-d-maltopyranoside; DDM) after proteolytic removal of MBP tag. b, 2D class averages of negatively stained particles in DDM. c, d, Two views of a random conical tilt (RCT) reconstruction from negatively stained TRPV1 in DDM. The RCT reconstruction was low-pass filtered at 30 Å, and fitted with the structure of NaVAb (PDB 3RVY) to indicate the size and general shape. e, Gel-filtration profile (Superdex-200) of purified minimal TRPV1 protein after exchange from DDM into amphipols. The major species elutes as a symmetrical peak after the void volume (V0). f, Representative negative-stain image of purified minimal TRPV1 protein without MBP tag in amphipols. g, 2D class averages of negative-stain particles in amphipols.
