Figure 8.

AziSEVO photolabeled residues within the α₁-subunits of α₁β₃ and α₁β₃γ_2L GABA_A receptors. Mass spectra of α₁-subunit AziSEVO photolabeled residues α₁-M1′ C234 (A) and α₁-M1′ S241 (B) within α₁β₃ and α₁β₃γ_2L GABA_A receptors, respectively. Above the spectra are the subunit peptide sequences that contain the α₁-subunit transmembrane helices. Focused view of the spectrum within ∼425–900 (A) and 325–800 m/z (B), with b (red), y (blue), and precursor ions (green) shown. Predicted photolabeled residue is shown in bold, underlined, and is indicated by a magenta asterisk. See the Supplemental Material for associated peptide fragment tables.