TY - JOUR
T1 - ATP binding by NLRP7 is required for inflammasome activation in response to bacterial lipopeptides
AU - Radian, Alexander D.
AU - Khare, Sonal
AU - Chu, Lan H.
AU - Dorfleutner, Andrea
AU - Stehlik, Christian
N1 - Funding Information:
This work was supported by the National Institutes of Health ( GM071723 , AI099009 and AR064349 to C.S., AR057532 and AR066739 to A.D.), the Skin Disease Research Center ( AR057216 ) and the American Heart Association ( 12GRNT12080035 ) to C.S., S.K. was an Arthritis Foundation fellow ( AF161715 ) and L.H.C. was supported by the Vietnam Education Foundation and the American Heart Association ( 15PRE25700116 ). Plasmids pMD2.G and psPAX2 were kindly provided by Didier Trono (École Polytechnique Fédérale de Lausanne).
PY - 2015/10/1
Y1 - 2015/10/1
N2 - Nucleotide-binding oligimerization domain (NOD)-like receptors (NLRs) are pattern recognition receptors (PRRs) involved in innate immune responses. NLRs encode a central nucleotide-binding domain (NBD) consisting of the NAIP, CIITA, HET-E and TP1 (NACHT) domain and the NACHT associated domain (NAD), which facilitates receptor oligomerization and downstream inflammasome signaling. The NBD contains highly conserved regions, known as Walker motifs, that are required for nucleotide binding and hydrolysis. The NLR containing a PYRIN domain (PYD) 7 (NLRP7) has been recently shown to assemble an ASC and caspase-1-containing high molecular weight inflammasome complex in response to microbial acylated lipopeptides and Staphylococcus aureus infection. However, the molecular mechanism responsible for NLRP7 inflammasome activation is still elusive. Here we demonstrate that the NBD of NLRP7 is an ATP binding domain and has ATPase activity. We further show that an intact nucleotide-binding Walker A motif is required for NBD-mediated nucleotide binding and hydrolysis, oligomerization, and NLRP7 inflammasome formation and activity. Accordingly, THP-1 cells expressing a mutated Walker A motif display defective NLRP7 inflammasome activation, interleukin (IL)-1β release and pyroptosis in response to acylated lipopeptides and S. aureus infection. Taken together, our results provide novel insights into the mechanism of NLRP7 inflammasome assembly.
AB - Nucleotide-binding oligimerization domain (NOD)-like receptors (NLRs) are pattern recognition receptors (PRRs) involved in innate immune responses. NLRs encode a central nucleotide-binding domain (NBD) consisting of the NAIP, CIITA, HET-E and TP1 (NACHT) domain and the NACHT associated domain (NAD), which facilitates receptor oligomerization and downstream inflammasome signaling. The NBD contains highly conserved regions, known as Walker motifs, that are required for nucleotide binding and hydrolysis. The NLR containing a PYRIN domain (PYD) 7 (NLRP7) has been recently shown to assemble an ASC and caspase-1-containing high molecular weight inflammasome complex in response to microbial acylated lipopeptides and Staphylococcus aureus infection. However, the molecular mechanism responsible for NLRP7 inflammasome activation is still elusive. Here we demonstrate that the NBD of NLRP7 is an ATP binding domain and has ATPase activity. We further show that an intact nucleotide-binding Walker A motif is required for NBD-mediated nucleotide binding and hydrolysis, oligomerization, and NLRP7 inflammasome formation and activity. Accordingly, THP-1 cells expressing a mutated Walker A motif display defective NLRP7 inflammasome activation, interleukin (IL)-1β release and pyroptosis in response to acylated lipopeptides and S. aureus infection. Taken together, our results provide novel insights into the mechanism of NLRP7 inflammasome assembly.
KW - ATPase
KW - Caspase-1
KW - IL-1β
KW - Inflammation
KW - Nod like receptor
KW - Staphylococcus aureus
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UR - http://www.scopus.com/inward/citedby.url?scp=84940962018&partnerID=8YFLogxK
U2 - 10.1016/j.molimm.2015.06.013
DO - 10.1016/j.molimm.2015.06.013
M3 - Article
C2 - 26143398
AN - SCOPUS:84940962018
VL - 67
SP - 294
EP - 302
JO - Molecular Immunology
JF - Molecular Immunology
SN - 0161-5890
IS - 2
ER -