Applying Thermal Proteome Profiling to Per- and Polyfluoroalkyl Substances (PFAS): Proteome-Wide Identification of
Xuehan Zheng1,2, Yanan Li3,4, Hua Qin2,5
1Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
Abstract:
Conventional target screening repertoires provide limited coverage of proteome-level interactions, leaving critical gaps in the mechanistic toxicology of per- and polyfluoroalkyl substances (PFAS). In this study, thermal proteome profiling (TPP) was applied for unbiased, proteome-wide characterization of PFAS-protein interactions across five representative PFAS, identifying 173 proteins with significant ligand-induced stabilization. Specifically, legacy PFAS converged on small COPII coat GTPase SAR1A/SAR1B, consistent with potential mechanistic Target of Rapamycin (mTOR)-linked metabolic reprogramming, whereas the replacement ether PFAS hexafluoropropylene oxide dimer acid (HFPO-DA, commercially known as GenX) showed a distinct targetome highlighted by WD repeat-containing protein 89 (WDR89), suggesting non-nuclear-receptor mechanisms plausibly related to chromatin/complex assembly. Cellular thermal shift assay and molecular docking independently verified target engagement and provided a structural rationale for the observed stabilization patterns. Further ontology-based annotation linked the stabilized targets to 279 standardized disease entities, with a predominance of neoplastic outcomes. These findings demonstrate TPP as a new approach methodology for PFAS target discovery, reveal divergent early events for legacy versus replacement chemistries, and provide a proteome-scale framework to prioritize mechanism-based validation and to support evidence-weighted risk assessment of emerging fluorinated alternatives.
