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Stafford, C. A.

Publications and source records attributed to Stafford, C. A..

2 recordsLinked to original sources

Phosphoproteome profiling uncovers a key role for CDKs in TNF signaling

Tumor necrosis factor (TNF) is one of the few cytokines successfully targeted by therapies against inflammatory diseases. However, blocking this well studied and pleiotropic ligand can cause dramatic side-effects. We reasoned that a systems-level proteomic analysis of TNF signaling could dissect its diverse functions and offer a base for developing more targeted therapies. Combining phosphoproteomics time course experiments with subcellular localization and kinase inhibitor analysis identifies functional modules of phosphorylations. The majority of regulated phosphorylations could be assigned to an upstream kinase by inhibiting master kinases and spatial proteomics revealed phosphorylation-dependent translocations of hundreds of proteins upon TNF stimulation. Phosphoproteome analysis of TNF-induced apoptosis and necroptosis uncovered a key role for transcriptional cyclin-dependent kinase (CDK) activity to promote cytokine production and prevent excessive cell death downstream of the TNF signaling receptor. Our comprehensive interrogation of TNF induced pathways and sites can be explored at http://tnfviewer.biochem.mpg.de/. Highlights- Distinct phosphorylation events mark early and late TNF signaling - Inhibition of master kinases reveals TNF stimulation dependent kinase-substrate relations - TNF induces phosphorylation-dependent spatial rearrangement of hundreds of proteins - CDK kinase activity promotes TNF-induced cytokine expression and inhibits cell death - CDK12/13 inhibitors have potential as anti-inflammatory agents

systems biology↗

Priming enables a NEK7-independent route of NLRP3 activation

The NLRP3 inflammasome plays a central role in antimicrobial defense, as well as in sterile inflammatory conditions. NLRP3 activity is governed by two independent signals. The first signal primes NLRP3, allowing it to respond to its activation signal. In the murine system, the mitotic spindle kinase NEK7 has been identified as a crucial factor in relaying the activation signal to NLRP3. Here we show that the requirement for NEK7 can be bypassed by TAK1-dependent post-translational priming. Under pro-inflammatory conditions that activate TAK1, NEK7 was dispensable for NLRP3 inflammasome formation in human and murine cells. Intriguingly, dissecting the NEK7 requirement in iPSC-derived primary human macrophages revealed that this NEK7-independent mechanism constitutes the predominant NLRP3 priming pathway in these cells. In summary, our results suggest that NEK7 functions as an NLRP3 priming - rather than activation - factor that can work in synergy or redundancy with other priming pathways to accelerate inflammasome activation.

immunology↗