Cell metabolism regulates integrin mechanosensing via an SLC3A2-dependent sphingolipid biosynthesis pathway

Nat Commun. 2018 Nov 19;9(1):4862. doi: 10.1038/s41467-018-07268-w.

Abstract

Mechanical and metabolic cues independently contribute to the regulation of cell and tissue homeostasis. However, how they cross-regulate each other during this process remains largely unknown. Here, we show that cellular metabolism can regulate integrin rigidity-sensing via the sphingolipid metabolic pathway controlled by the amino acid transporter and integrin coreceptor CD98hc (SLC3A2). Genetic invalidation of CD98hc in dermal cells and tissue impairs rigidity sensing and mechanical signaling downstream of integrins, including RhoA activation, resulting in aberrant tissue mechanical homeostasis. Unexpectedly, we found that this regulation does not occur directly through regulation of integrins by CD98hc but indirectly, via the regulation of sphingolipid synthesis and the delta-4-desaturase DES2. Loss of CD98hc decreases sphingolipid availability preventing proper membrane recruitment, shuttling and activation of upstream regulators of RhoA including Src kinases and GEF-H1. Altogether, our results unravel a novel cross-talk regulation between integrin mechanosensing and cellular metabolism which may constitute an important new regulatory framework contributing to mechanical homeostasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dermis / cytology
  • Dermis / metabolism
  • Fibroblasts / cytology
  • Fibroblasts / metabolism*
  • Fusion Regulatory Protein 1, Heavy Chain / deficiency
  • Fusion Regulatory Protein 1, Heavy Chain / genetics*
  • Gene Expression Regulation
  • Homeostasis
  • Lipogenesis
  • Mechanotransduction, Cellular*
  • Mice
  • Mice, Transgenic
  • Multienzyme Complexes / genetics*
  • Multienzyme Complexes / metabolism
  • Oxidoreductases / genetics*
  • Oxidoreductases / metabolism
  • Primary Cell Culture
  • Rho Guanine Nucleotide Exchange Factors / genetics
  • Rho Guanine Nucleotide Exchange Factors / metabolism
  • Sphingolipids / biosynthesis*
  • rho GTP-Binding Proteins / genetics
  • rho GTP-Binding Proteins / metabolism
  • rhoA GTP-Binding Protein
  • src-Family Kinases / genetics
  • src-Family Kinases / metabolism

Substances

  • Arhgef2 protein, mouse
  • Fusion Regulatory Protein 1, Heavy Chain
  • Multienzyme Complexes
  • Rho Guanine Nucleotide Exchange Factors
  • Slc3A2 protein, mouse
  • Sphingolipids
  • Degs2 protein, mouse
  • Oxidoreductases
  • src-Family Kinases
  • RhoA protein, mouse
  • rho GTP-Binding Proteins
  • rhoA GTP-Binding Protein