Sequestosome-1/p62 is the key intracellular target of innate defense regulator peptide

Hong Bing Yu, Agnieszka Kielczewska, Annett Rozek, Shunsuke Takenaka, Yuling Li, Lisa Thorson, Robert E.W. Hancock, M. Marta Guarna, John R. North, Leonard J. Foster, Oreola Donini, B. Brett Finlay

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61 Citations (Scopus)


Innate defense regulator-1 (IDR-1) is a synthetic peptide with no antimicrobial activity that enhances microbial infection control while suppressing inflammation. Previously, the effects of IDR-1 were postulated to impact several regulatory pathways including mitogen-activated protein kinase (MAPK) p38 and CCAAT-enhancer-binding protein, but how this was mediated was unknown. Using a combined stable isotope labeling by amino acids in cell culture-proteomics methodology, we identified the cytoplasmic scaffold protein p62 as the molecular target of IDR-1. Direct IDR-1 binding to p62 was confirmed by several biochemical binding experiments, and the p62 ZZ-type zinc finger domain was identified as the IDR-1 binding site. Co-immunoprecipitation analysis of p62 molecular complexes demonstrated that IDR-1 enhanced the tumor necrosis factor α-induced p62 receptor-interacting protein 1 (RIP1) complex formation but did not affect tumor necrosis factor α-induced p62-protein kinase ζ complex formation. In addition, IDR-1 induced p38MAPKactivity in a p62-dependent manner and increased CCAAT-enhancer-binding protein β activity, whereas NF-κB activity was unaffected. Collectively, these results demonstrate that IDR-1 binding to p62 specifically affects protein-protein interactions and subsequent downstream events. Our results implicate p62 in the molecular mechanisms governing innate immunity and identify p62 as a potential therapeutic target in both infectious and inflammatory diseases.

Original languageEnglish
Pages (from-to)36007-36011
Number of pages5
JournalJournal of Biological Chemistry
Issue number52
Publication statusPublished or Issued - 25 Dec 2009
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

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