PYNOD, a novel Apaf-1/CED4-like protein is an inhibitor of ASC and caspase-1

Int Immunol. 2004 Jun;16(6):777-86. doi: 10.1093/intimm/dxh081. Epub 2004 Apr 19.


Recently, a large subfamily of nucleotide-binding and oligomerization domain-containing proteins that have an N-terminal pyrin-like domain and C-terminal leucine-rich repeats has been described. In this study, we identified PYNOD, a novel member of this family that lacks the leucine-rich repeats. We found that human PYNOD mRNA is expressed in various tissues and at high levels in heart, skeletal muscle and brain. It is also expressed in various cell lines, including haematopoietic cell lines. PYNOD oligomerizes and binds to ASC, an adaptor protein that plays a role in apoptotic and inflammatory signal transduction, and to caspase-1 and IL-1beta. PYNOD inhibits apoptosis-associated speck-like protein containing a CARD (ASC)-mediated NF-kappaB activation and apoptosis, and caspase-1-mediated IL-1beta maturation, and it does so in the presence and absence of constitutively active mutants of CARD12 and PYPAF1, which are enhancers of these processes. Thus, PYNOD is a novel regulator of apoptosis and inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Amino Acid Sequence
  • Animals
  • Apoptosis Regulatory Proteins
  • Apoptosis*
  • Apoptotic Protease-Activating Factor 1
  • CARD Signaling Adaptor Proteins
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / physiology*
  • Caspase Inhibitors*
  • Cell Line
  • Cysteine Proteinase Inhibitors / chemistry
  • Cysteine Proteinase Inhibitors / genetics
  • Cysteine Proteinase Inhibitors / metabolism
  • Cytoskeletal Proteins / antagonists & inhibitors*
  • Gene Expression / genetics
  • Humans
  • Interleukin-1 / metabolism
  • Mice
  • Molecular Sequence Data
  • NF-kappa B / metabolism
  • Protein Binding
  • Proteins / genetics
  • Proteins / metabolism
  • RNA, Messenger / analysis
  • Rats
  • Sequence Homology, Amino Acid


  • APAF1 protein, human
  • Adaptor Proteins, Signal Transducing
  • Apaf1 protein, mouse
  • Apaf1 protein, rat
  • Apoptosis Regulatory Proteins
  • Apoptotic Protease-Activating Factor 1
  • CARD Signaling Adaptor Proteins
  • Carrier Proteins
  • Caspase Inhibitors
  • Cysteine Proteinase Inhibitors
  • Cytoskeletal Proteins
  • Interleukin-1
  • NF-kappa B
  • NLRP10 protein, human
  • PYCARD protein, human
  • Proteins
  • Pycard protein, mouse
  • Pycard protein, rat
  • RNA, Messenger