Structural and Functional Analysis of the NLRP4 Pyrin Domain
Open Access
- 6 September 2012
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 51 (37), 7330-7341
- https://doi.org/10.1021/bi3007059
Abstract
NLRP4 is a member of the nucleotide-binding and leucine-rich repeat receptor (NLR) family of cytosolic receptors and a member of an inflammation signaling cascade. Here, we present the crystal structure of the NLRP4 pyrin domain (PYD) at 2.3 Å resolution. The NLRP4 PYD is a member of the death domain (DD) superfamily and adopts a DD fold consisting of six α-helices tightly packed around a hydrophobic core, with a highly charged surface that is typical of PYDs. Importantly, however, we identified several differences between the NLRP4 PYD crystal structure and other PYD structures that are significant enough to affect NLRP4 function and its interactions with binding partners. Notably, the length of helix α3 and the α2-α3 connecting loop in the NLRP4 PYD are unique among PYDs. The apoptosis-associated speck-like protein containing a CARD (ASC) is an adaptor protein whose interactions with a number of distinct PYDs are believed to be critical for activation of the inflammatory response. Here, we use co-immunoprecipitation, yeast two-hybrid, and nuclear magnetic resonance chemical shift perturbation analysis to demonstrate that, despite being important for activation of the inflammatory response and sharing several similarities with other known ASC-interacting PYDs (i.e., ASC2), NLRP4 does not interact with the adaptor protein ASC. Thus, we propose that the factors governing homotypic PYD interactions are more complex than the currently accepted model, which states that complementary charged surfaces are the main determinants of PYD-PYD interaction specificity.Keywords
Funding Information
- National Institutes of Health
This publication has 68 references indexed in Scilit:
- Detection of Spatial Correlations in Protein Structures and Molecular ComplexesStructure, 2012
- The NLRP12 Pyrin Domain: Structure, Dynamics, and Functional InsightsJournal of Molecular Biology, 2011
- Three-dimensional Structure of the NLRP7 Pyrin DomainJournal of Biological Chemistry, 2010
- Structure and Interdomain Dynamics of Apoptosis-associated Speck-like Protein Containing a CARD (ASC)Journal of Biological Chemistry, 2009
- Overcoming the solubility limit with solubility-enhancement tags: successful applications in biomolecular NMR studiesJournal of Biomolecular NMR, 2009
- The Fas–FADD death domain complex structure unravels signalling by receptor clusteringNature, 2008
- The NLR Gene Family: A Standard NomenclatureImmunity, 2008
- Death Domain Assembly Mechanism Revealed by Crystal Structure of the Oligomeric PIDDosome Core ComplexCell, 2007
- Crystal structure of the Nod1 caspase activation and recruitment domainBiochemical and Biophysical Research Communications, 2007
- Electrostatics of nanosystems: Application to microtubules and the ribosomeProceedings of the National Academy of Sciences of the United States of America, 2001