Perfluorooctane sulfonate induces autophagy-dependent lysosomal membrane permeabilization by weakened interaction between tyrosinated alpha-tubulin and spinster 1

Food Chem Toxicol. 2021 Nov:157:112540. doi: 10.1016/j.fct.2021.112540. Epub 2021 Sep 6.

Abstract

Perfluorooctane sulfonate (PFOS) is one kind of persistent organic pollutants. In previous study, we found that PFOS induced autophagy-dependent lysosomal membrane permeabilization (LMP) in hepatocytes, and siRNA against lysosomal permease spinster 1 (SPNS1) relieved PFOS-induced LMP. However, whether and how SPNS1 functioned as the link between autophagy and LMP was still not defined. In this study, we constructed a stable cell line expressing high levels of SPNS1. We found that SPNS1 interacted specifically with α-tubulin of tyrosinated isotype by pull-down assay. After treatment with PFOS, the level of tyrosinated α-tubulin was autophagy-dependently decreased. SPNS1-tyrosinated α-tubulin interaction was disrupted subsequently, which led to LMP eventually. We also found that stable high-expression of SPNS1 in hepatocytes accelerated lysosomal acidification, and deteriorated PFOS-induced LMP. This study pointed out that SPNS1-tyrosinated α-tubulin interaction mediated the cross-talk between autophagy and LMP induced by PFOS, shedding new light on the mechanism of PFOS hepatotoxicity.

Keywords: Autophagy; Lysosomal membrane permeabilization; Perfluorooctane sulfonate; Spinster 1; Tyrosinated α-tubulin.

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Autophagy / drug effects*
  • Blotting, Western
  • Fluorocarbons / pharmacology*
  • Hep G2 Cells / drug effects
  • Humans
  • Lysosomes / drug effects*
  • Mass Spectrometry
  • Membrane Proteins / metabolism*
  • Membranes / drug effects
  • Permeability / drug effects
  • Tubulin / metabolism*
  • Tyrosine / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • Fluorocarbons
  • LAT protein, human
  • Membrane Proteins
  • Tubulin
  • Tyrosine
  • perfluorooctane