Release of nonmuscle myosin II from the cytosolic domain of tumor necrosis factor receptor 2 is required for target gene expression.

Published online

Journal Article

Tumor necrosis factor-α (TNF-α) elicits its biological activities through activation of TNF receptor 1 (TNFR1, also known as p55) and TNFR2 (also known as p75). The activities of both receptors are required for the TNF-α-induced proinflammatory response. The adaptor protein TNFR-associated factor 2 (TRAF2) is critical for either p55- or p75-mediated activation of nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling, as well as for target gene expression. We identified nonmuscle myosin II (myosin) as a binding partner of p75. TNF-α-dependent signaling by p75 and induction of target gene expression persisted substantially longer in cells deficient in myosin regulatory light chain (MRLC; a component of myosin) than in cells replete in myosin. In resting endothelial cells, myosin was bound constitutively to the intracellular region of p75, a region that overlaps with the TRAF2-binding domain, and TNF-α caused the rapid dissociation of myosin from p75. At early time points after exposure to TNF-α, p75 activated Rho-associated kinase 1 (ROCK1). Inhibition of ROCK1 activity blocked TNF-α-dependent phosphorylation of MRLC and the dissociation of myosin from p75. ROCK1-dependent release of myosin was necessary for the TNF-α-dependent recruitment of TRAF2 to p75 and for p75-specific activation of NF-κB and MAPK signaling. Thus, our findings have revealed a previously uncharacterized, noncanonical regulatory function of myosin in cytokine signaling.

Full Text

Duke Authors

Cited Authors

  • Chandrasekharan, UM; Dechert, L; Davidson, UI; Waitkus, M; Mavrakis, L; Lyons, K; Beach, JR; Li, X; Egelhoff, TT; Fox, PL; DiCorleto, PE

Published Date

  • July 16, 2013

Published In

Volume / Issue

  • 6 / 284

Start / End Page

  • ra60 -

PubMed ID

  • 23861542

Pubmed Central ID

  • 23861542

Electronic International Standard Serial Number (EISSN)

  • 1937-9145

Digital Object Identifier (DOI)

  • 10.1126/scisignal.2003743

Language

  • eng

Conference Location

  • United States