Identification of DAPK as a scaffold protein for the LIMK/cofilin complex in TNF-induced apoptosis

Int J Biochem Cell Biol. 2013 Aug;45(8):1720-9. doi: 10.1016/j.biocel.2013.05.013. Epub 2013 May 20.


The role of cytoskeleton-associated proteins during TNF-induced apoptosis is not fully understood. A potential candidate kinase that might connect TNF signaling to actin reorganization is the death-associated protein kinase (DAPK). To identify new DAPK interaction partners in TNF-induced apoptosis, we performed a peptide array screen. We show that TNF-treatment enhanced the phosphorylation of LIMK at threonine508 and its downstream target cofilin at serine3 (p-cofilin(Ser3)). Modulation of DAPK activity and expression by DAPK inhibitor treatment, siRNA knockdown, and overexpression affected the phosphorylation of both proteins. We propose a 3D structural model where DAPK functions as a scaffold for the LIMK/cofilin complex and triggers a closer interaction of both proteins under TNF stimulation. Upon TNF a striking redistribution of LIMK, DAPK, and cofilin to the perinuclear compartment was observed. The pro-apoptotic DAPK/LIMK/cofilin multiprotein complex was abrogated in detached cells, indicating that its signaling was no longer needed if cells committed to apoptosis. P-cofilin(Ser3) was strongly accumulated in cells with condensed chromatin, pronounced membrane blebs and Annexin V up-regulation. From studying different cofilin(Ser3) mutants we suggest that p-cofilin(Ser3) is an indicator of TNF-induced apoptosis. Collectively, our findings identify a novel molecular cytoskeleton-associated mechanism in TNF-induced DAPK-dependent apoptosis.

Keywords: Apoptosis; Cofilin; DAPK; LIMK; TNF.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Apoptosis / drug effects*
  • Cell Adhesion / drug effects
  • Cofilin 1 / chemistry
  • Cofilin 1 / metabolism*
  • Death-Associated Protein Kinases / metabolism*
  • HCT116 Cells
  • Humans
  • Lim Kinases / metabolism*
  • Models, Biological
  • Models, Molecular
  • Molecular Sequence Data
  • Multiprotein Complexes / metabolism*
  • Phosphorylation / drug effects
  • Protein Binding / drug effects
  • Protein Transport / drug effects
  • Signal Transduction / drug effects
  • Tumor Necrosis Factor-alpha / pharmacology*


  • Cofilin 1
  • Multiprotein Complexes
  • Tumor Necrosis Factor-alpha
  • Death-Associated Protein Kinases
  • Lim Kinases