Direct visualization by FRET-FLIM of a putative mechanosome complex involving Src, Pyk2 and MBD2 in living MLO-Y4 cells

PLoS One. 2021 Dec 23;16(12):e0261660. doi: 10.1371/journal.pone.0261660. eCollection 2021.

Abstract

Earlier, we proposed the "mechanosome" concept as a testable model for understanding how mechanical stimuli detected by cell surface adhesion molecules are transmitted to modulate gene expression inside cells. Here, for the first time we document a putative mechanosome involving Src, Pyk2 and MBD2 in MLO-Y4 osteocytes with high spatial resolution using FRET-FLIM. Src-Pyk2 complexes were concentrated at the periphery of focal adhesions and the peri-nuclear region. Pyk2-MBD2 complexes were located primarily in the nucleus and peri-nuclear region. Lifetime measurements indicated that Src and MBD2 did not interact directly. Finally, mechanical stimulation by fluid flow induced apparent accumulation of Src-Pyk2 protein complexes in the peri-nuclear/nuclear region, consistent with the proposed behavior of a mechanosome in response to a mechanical stimulus.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Line
  • DNA-Binding Proteins / analysis
  • DNA-Binding Proteins / metabolism*
  • Fluorescence Resonance Energy Transfer
  • Focal Adhesion Kinase 2 / analysis
  • Focal Adhesion Kinase 2 / metabolism*
  • Focal Adhesions / metabolism
  • Mechanotransduction, Cellular
  • Mice
  • Osteocytes / cytology
  • Osteocytes / metabolism*
  • src-Family Kinases / analysis
  • src-Family Kinases / metabolism*

Substances

  • DNA-Binding Proteins
  • Mbd2 protein, mouse
  • Focal Adhesion Kinase 2
  • Ptk2b protein, mouse
  • src-Family Kinases