Figure 4. Identification of proteins enriched by SMALP extraction.

(A) Number of identified proteins in affinity pull-down samples solubilised with or without SMA, two-tailed t-test, **p<0.01, n=6 or 8 replicates per condition. (B) MS/MS spectrum counts from samples solubilised with or without SMA, ns = not significant after two-tailed t-test with n=6 or 8. (C) Calculated hydrophobicity score of amino acid residues found in protein sequences obtained with and without SMA solubilisation, ****p<0.0001, two-tailed t-test, n=3 per condition. (D) GO term (cellular compartment) enrichment of proteins identified with and without SMA solubilisation, n=4 or 11. (E) Predicted numbers of proteins containing transmembrane helices obtained with or without SMA solubilisation, n=4 or 8. (F, G) Analysis of solubility and hydrophobicity of receptors identified with and without SMA solubilisation (r² = –0.56, p<0.0001, n=4) and of transmembrane receptor helices (r²=0.56, p < 0.01, n = 4). (H) Solubility score of individual nAChR subunits.

Figure 4—figure supplement 1. GO terms and predicted membrane proteins.

(A) GO slim term for biological process and (B) for molecular function analysed within samples solubilised without or with SMA, n=4 or 11 per conditions. Predicted β-barrel membrane- (C), two-tailed t-test ****p<0.0001, n=6 or 10; palmitoylated- (D), ****p<0.0001, each n=8; myristoylated- (E), ****p<0.0001, n=6 or 10; and GPI-anchored proteins (F), non-significant ns, n=6 or 10.