6k7v
From Proteopedia
Structure of NLRP1 CARD filament
Structural highlights
Disease[NLRP1_HUMAN] Vitiligo-associated autoimmune disease;Vitiligo;Corneal intraepithelial dyskeratosis with palmoplantar hyperkeratosis and laryngeal dyskeratosis. Disease susceptibility is associated with variations affecting the gene represented in this entry. The disease is caused by mutations affecting the gene represented in this entry. The disease may be caused by mutations affecting the gene represented in this entry. Function[NLRP1_HUMAN] As the sensor component of the NLRP1 inflammasome, plays a crucial role in innate immunity and inflammation. In response to pathogens and other damage-associated signals, initiates the formation of the inflammasome polymeric complex, made of NLRP1, CASP1, and possibly PYCARD. Recruitment of proCASP1 to the inflammasome promotes its activation and CASP1-catalyzed IL1B and IL18 maturation and secretion in the extracellular milieu. Activation of NLRP1 inflammasome is also required for HMGB1 secretion. The active cytokines and HMGB1 stimulate inflammatory responses. Inflammasomes can also induce pyroptosis, an inflammatory form of programmed cell death (PubMed:22665479, PubMed:17418785). May be activated by muramyl dipeptide (MDP), a fragment of bacterial peptidoglycan, in a NOD2-dependent manner (PubMed:18511561). Contrary to its mouse ortholog, not activated by Bacillus anthracis lethal toxin (PubMed:19651869). It is unclear whether isoform 2 is involved in inflammasome formation. It is not cleaved within the FIIND domain, does not assemble into specks, nor promote IL1B release (PubMed:22665479). However, in an vitro cell-free system, it has been shown to be activated by MDP (PubMed:17349957). Binds ATP (PubMed:11113115, PubMed:15212762).[UniProtKB:A1Z198][1] [2] [3] [4] [5] [6] [7] [8] Publication Abstract from PubMedNod-like receptor (NLR) proteins activate pyroptotic cell death and IL-1 driven inflammation by assembling and activating the inflammasome complex. Closely related sensor proteins NLRP1 and CARD8 undergo unique auto-proteolysis-dependent activation and are implicated in auto-inflammatory diseases; however, their mechanisms of activation are not understood. Here we report the structural basis of how the activating domains (FIIND(UPA)-CARD) of NLRP1 and CARD8 self-oligomerize to assemble distinct inflammasome complexes. Recombinant FIIND(UPA)-CARD of NLRP1 forms a two-layered filament, with an inner core of oligomerized CARD surrounded by an outer ring of FIIND(UPA). Biochemically, self-assembled NLRP1-CARD filaments are sufficient to drive ASC speck formation in cultured human cells-a process that is greatly enhanced by NLRP1-FIIND(UPA) which forms oligomers in vitro. The cryo-EM structures of NLRP1-CARD and CARD8-CARD filaments, solved here at 3.7 A, uncover unique structural features that enable NLRP1 and CARD8 to discriminate between ASC and pro-caspase-1. In summary, our findings provide structural insight into the mechanisms of activation for human NLRP1 and CARD8 and reveal how highly specific signaling can be achieved by heterotypic CARD interactions within the inflammasome complexes. Structural basis for distinct inflammasome complex assembly by human NLRP1 and CARD8.,Gong Q, Robinson K, Xu C, Huynh PT, Chong KHC, Tan EYJ, Zhang J, Boo ZZ, Teo DET, Lay K, Zhang Y, Lim JSY, Goh WI, Wright G, Zhong FL, Reversade B, Wu B Nat Commun. 2021 Jan 8;12(1):188. doi: 10.1038/s41467-020-20319-5. PMID:33420028[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
Categories: Human | Large Structures | Gong, Q | Wu, B | Xu, C | Zhang, J | Filament | Signaling protein