Figure 4. Biochemical constraints revealed by proteomic mapping.

(A) Schematic illustrating possible molecular mechanisms of cis and trans regulation (B) Effect size of protein-altering, synonymous, and regulatory cis-pQTNs, as indicated. Boxes show median and upper and lower quartiles; whiskers show 1.5 times the interquartile range. (C) Effect size of protein-altering, synonymous, and regulatory trans-pQTNs, as indicated. Boxes show median and upper and lower quartiles; whiskers show 1.5 times the interquartile range. p values by two-sided t test. (D) Predicted effect from genetic mapping of the IRA2^Asn201Ser missense variant on Mcr1 levels. p value by F test. (E) CRISPR reconstruction and mass spectrometry to validate the effect of the IRA2^Asn201Ser variant on Mcr1 levels. n = 15; p value by two-sided t test. (F) BLOSUM62 (top) and FoldX scores (bottom) for missense trans-pQTNs (blue) as compared to all other segregating missense variants (grey). Boxes show median and upper and lower quartiles; whiskers show 1.5 times the interquartile range. p values by Mann-Whitney U test. (G) Illustrative conservative pQTN substitutions and (H) perturbative pQTN substitutions with functional domains of the mutated proteins indicated. (I) Solvent-accessible surface area and number of C_α within 10Å for all possible missense SNPs (purple; also shown are subsets resulting from transitions and transversions) and all missense variants segregating in the F₆ mapping panel (grey). (J) As in (I) for all possible missense SNPs (purple), missense pQTNs identified in this study (blue), and all other missense variants segregating in the F₆ mapping panel (grey). p values by Mann-Whitney U test. See also Figure S4.