title: ATP binding by monarch-1/NLRP12 is critical for its inhibitory function.
abstract: The recently discovered nucleotide binding domain-leucine rich repeat (NLR) gene family is conserved from plants to mammals, and several members are associated with human autoinflammatory or immunodeficiency disorders. This family is defined by a central nucleotide binding domain that contains the highly conserved Walker A and Walker B motifs. Although the nucleotide binding domain is a defining feature of this family, it has not been extensively studied in its purified form. In this report, we show that purified Monarch-1/NLRP12, an NLR protein that negatively regulates NF-kappaB signaling, specifically binds ATP and exhibits ATP hydrolysis activity. Intact Walker A/B motifs are required for this activity. These motifs are also required for Monarch-1 to undergo self-oligomerization, Toll-like receptor- or CD40L-activated association with NF-kappaB-inducing kinase (NIK) and interleukin-1 receptor-associated kinase 1 (IRAK-1), degradation of NIK, and inhibition of IRAK-1 phosphorylation. The stable expression of a Walker A/B mutant in THP-1 monocytes results in increased production of proinflammatory cytokines and chemokines to an extent comparable to that in cells in which Monarch-1 is silenced via short hairpin RNA. The results of this study are consistent with a model wherein ATP binding regulates the anti-inflammatory activity of Monarch-1.
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina, CB7295, 450 West St., Chapel Hill, NC 27599, USA.
authors.forename: Zhengmao
authors.initials: Z
authors.lastname: Ye
authors.forename: John D
authors.initials: JD
authors.lastname: Lich
authors.forename: Chris B
authors.initials: CB
authors.lastname: Moore
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Duncan
authors.forename: Kristi L
authors.initials: KL
authors.lastname: Williams
authors.forename: Jenny P-Y
authors.initials: JP
authors.lastname: Ting
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D019013:CD40 Antigens / Q000494:pharmacology; D002460:Cell Line; D018925:Chemokines / Q000032:analysis; D016207:Cytokines / Q000032:analysis; D018076:DNA, Complementary / Q000235:genetics; D004789:Enzyme Activation; D004926:Escherichia coli / Q000235:genetics; D006388:Hemagglutinins / Q000378:metabolism; D006801:Humans; D053592:Interleukin-1 Receptor-Associated Kinases / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007668:Kidney / Q000166:cytology; D008969:Molecular Sequence Data; D009000:Monocytes / Q000187:drug effects; D009154:Mutation; D011233:Precipitin Tests; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015183:Restriction Mapping; D013997:Time Factors; D014162:Transfection
chemical_list: D019013:CD40 Antigens; D018925:Chemokines; D016207:Cytokines; D018076:DNA, Complementary; D006388:Hemagglutinins; D047908:Intracellular Signaling Peptides and Proteins; C476731:NLRP12 protein, human; D011993:Recombinant Fusion Proteins; D000255:Adenosine Triphosphate; D053592:Interleukin-1 Receptor-Associated Kinases