Fas activation induces renal tubular epithelial cell beta 8 integrin expression and function in the absence of apoptosis

J Biol Chem. 2002 Dec 6;277(49):47826-33. doi: 10.1074/jbc.M204901200. Epub 2002 Sep 24.

Abstract

Cell fate following Fas (CD95) ligand or agonistic anti-Fas antibody stimulation is determined by multiple factors, including Fas expression level, microdomain localization, and modulating cytokines. Highly expressed Fas clusters and activates a canonical apoptosis signaling pathway. In less susceptible cells, Fas transduces apoptosis-independent signals, which are not well defined, but have been linked to inflammation, angiogenesis, and fibrosis. To identify apoptosis-independent Fas pathways, cultured renal tubular epithelial cells were stimulated with agonistic anti-Fas antibodies under conditions that did not cause cell death. Analysis of filter cDNA microarrays revealed beta(8) integrin subunit mRNA induction in Fas-stimulated cells. beta(8) integrin mRNA expression increased within 3-6 h of Fas ligation due to enhanced mRNA stabilization, and mRNA increases were sustained for 48-72 h. Expression of plasma membrane beta(8) integrin, as well as its heterodimer partner alpha(v), was increased by Fas activation with a similar kinetic pattern. Fas-induced alpha(v)beta(8) expression correlated with increased migration to vitronectin, the ligand for alpha(v)beta(8). Results from studies with function-blocking antibodies against other alpha(v)beta integrins or suppression of beta(8) integrin expression by RNA interference demonstrated that induced beta(8) integrin expression mediated Fas-stimulated migration. We conclude that alpha(v)beta(8) integrin induction defines an unexpected role for Fas in cell migration, rather than as a cell death receptor.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Apoptosis*
  • Biotinylation
  • Blotting, Northern
  • Cell Adhesion
  • Cell Death
  • Cell Line
  • Cell Membrane / metabolism
  • Cell Movement
  • DNA, Complementary / metabolism
  • Dactinomycin / pharmacology
  • Epithelial Cells / metabolism*
  • Humans
  • Integrin beta Chains / biosynthesis*
  • Integrins / metabolism
  • Kidney Tubules / metabolism*
  • Kinetics
  • Oligonucleotide Array Sequence Analysis
  • Protein Binding
  • Protein Biosynthesis
  • Protein Synthesis Inhibitors / pharmacology
  • RNA Interference
  • RNA, Messenger / metabolism
  • Time Factors
  • Transcription, Genetic
  • Transfection
  • Tumor Cells, Cultured
  • Up-Regulation
  • fas Receptor / metabolism*

Substances

  • DNA, Complementary
  • Integrin beta Chains
  • Integrins
  • Protein Synthesis Inhibitors
  • RNA, Messenger
  • fas Receptor
  • integrin alphavbeta8
  • integrin beta8
  • Dactinomycin