Fig. 1: Structure determination of CARD8-CT and NLRP1-CT filaments.
From: Mechanism of filament formation in UPA-promoted CARD8 and NLRP1 inflammasomes
a Domain architecture of human NLRP1 and CARD8, each with a C-terminal domain (CT) containing UPA-CARD. b CARD8 and NLRP1 activation pathway in which signals leading to NLRP1 and CARD8 activation target them to the proteasome for N-terminal degradation. This leads to the release of free CT oligomers, which assemble the inflammasome. The purification strategy bypasses N-terminal degradation by directly expressing MBP-CT fusion proteins and cleaving the tag in vitro. c Classification of different inflammasome sensors by their signaling through the adapter ASC. Human NLRP1 and CARD8 are ASC-dependent and ASC-independent, respectively. d Cryo-EM 2D classification of CARD8-CT filaments. e Gold-standard Fourier shell correlation (FSC) and map-model correlation plots of the CARD8-CT filament 3D reconstruction, which gave an overall resolution of 3.3 Å. f Local resolution of the CARD8-CT filament calculated with RELION’s local resolution estimation59,70 and colored as indicated. g Cryo-EM 2D classification of NLRP1-CT filaments. h FSC plots of the NLRP1-CT filament 3D reconstruction, which gave an overall resolution of 3.6 Å. i Local resolution of the NLRP1-CT filament with RELION’s local resolution estimation59,70 and colored as indicated.
