PFOS effects on root stem cell maintenance and regeneration by suppressing the stem cell factor PLT2

Perfluorooctane sulfonic acid (PFOS), a persistent organic pollutant, poses significant environmental risks due to its widespread contamination of agricultural systems. However, its phytotoxic mechanisms on Arabidopsis root growth and regeneration remain incompletely understood. In this study, we systematically investigated PFOS phytotoxicity and revealed its multimodal inhibitory effects on root growth, stem cell maintenance and regeneration. Our results demonstrated that PFOS exposure induced concentration-dependent reductions in primary root length, meristem size, and meristematic cortex cell number. Crucially, we observed downregulation of PLT2 expression in the root stem cell niche, whereas the auxin transporters PIN1/PIN2 and other key stem cell regulators (SHR, SCR, PLT1) remained largely unaltered under PFOS stress. This suppression of PLT2 correlated with both meristem dysfunction and impaired regeneration capacity. Furthermore, PFOS triggered oxidative stress and promoted root cell death. Taken together, these findings provide crucial insights into the mechanisms of PFOS phytotoxicity. The discovery of PLT2-mediated effects offers new perspectives for understanding how pollutants affect plant development and regeneration. • Perfluorooctane sulfonic acid (PFOS) inhibited Arabidopsis root length, meristem length, and cortex cell number. • PFOS toxicity inhibited root growth and regeneration by reducing PLT2 expression. • PFOS increased ROS stress and cell death in Arabidopsis roots.