Fig. 5: HDX-MS investigation of poly(A)-binding protein (Pab1) ortholog monomers and condensates reveals conservation of condensate structure.
From: An adaptive biomolecular condensation response is conserved across environmentally divergent species
a Pab1 ortholog deuterium (%D) exchange mapped onto aligned primary sequence (all data after 100 seconds of exchange). Domain boundaries are annotated in gray, peptides are light horizontal bars, and solid lines show peptide means at each site. b Correlation (Pearson R) of site-by-site %D exchange for Pab1 monomers between orthologs, with shuffled sites as a control. c Relative exchange (%D) in monomers after 100 seconds for secondary structure elements in S. cerevisiae Pab1 (PDB: 6R5K). Box and whisker plot is standard: box shows 25th and 75th percentile with median crossbar, whiskers show maxima/minima up to 1.5x the interquartile range, with outliers plotted as separate points. Residue counts for each element type are loop n = 355 (368 for K. marxianus only), helix n = 150, and strand n = 73 for all species. d Difference in %D exchange between condensate and monomer for the three Pab1 orthologs, annotated as in a. Condensates for S. cerevisiae and S. kudriavzevii were made by incubating protein at 46 °C for 20 min, K. marxianus condensates were made using three incubations: 46 °C for 20 min, then 50 °C for 10 min, then 55 °C for 10 min. e Correlation (Pearson R) of differences in %D uptake between condensate and monomer between pairwise species comparisons, with shuffled sites as a control. f Change in %D uptake after 100 seconds between condensate and monomer for Pab1 domains. Box and whisker representation is as in c. Embedded error bars show mean +/− standard error. For each domain, residue counts for the three species are: RRM1 n = 68, 75, 69; RRM2 n = 78, 71, 65; RRM3 n = 69, 75, 55; RRM4 n = 75, 78, 78; CTD n = 73, 73, 49. Source data are provided as a Source Data file.
