Project description:To understand to role of RIPK3 during tumor recurrence, we performed RNAseq to study the transcriptional response of mouse recurrent breast cancer cells to RIPK3 knockdown.
Project description:The molecular basis of tumor recurrence remain poorly understood. Here, we performed RNA microarrays to study the genetic basis of the phenotypic differences between the primary and recurrent breast cancer cells.
Project description:RIPK4 but not the related kinases RIPK1, RIPK2, and RIPK3 caused similar transcriptional changes to Wnt3a. PA1 cells were transfected by 8ug RIPK1, RIPK2, RIPK3, or RIPK4 for 48h, RNA were extracted and sequenced.
Project description:Pathogen recognition receptors and TNF superfamily members engage Receptor Interacting Serine/threonine Kinase-3 (RIPK3) to activate programmed cell death, including MLKL-mediated necroptosis and caspase-8-dependent apoptosis. However, the post-translational control of RIPK3 signalling is not fully understood. Using mass-spectrometry, we identified a novel ubiquitylation site on murine RIPK3 beyond the RIP homotypic interaction motif (RHIM) on K469. Complementation of RIPK3-deficient cells with a Ripk3K469R mutant demonstrated that the decoration of RIPK3 K469 by ubiquitin limits both RIPK3-mediated caspase-8 activation and apoptotic killing, in addition to RIPK3 autophosphorylation and MLKL-mediated necroptosis. Unexpectedly, the overall ubiquitylation of mutant RIPK3K469R was enhanced, which largely resulted from additional RIPK3 ubiquitylation on K359. Loss of RIPK3 K359 ubiquitylation reduced RIPK3K469R hyper-ubiquitylation and limited the ability of Ripk3K469R/K469R to trigger enhanced killing. Ripk3K469R/K469R mice challenged with Salmonella displayed increased bacterial loads in the spleen and liver, with reduced IFN serum levels. Therefore, RIPK3 K469 ubiquitylation can function to prevent RIPK3 ubiquitylation on alternate lysine residues, which otherwise promote RIPK3 oligomerization and consequent cell death signalling.
Project description:This purpose of this experiment was to investigate the transcriptional differences between C57BL6, RIPK3 knock-out mice infected with influenza strain A/CA/04/2009 (H1N1) virus. Overview of Experiment: Groups of 6-8 week-old C57BL6 and RIPK3 knock-out mice were infected with influenza A/CA/04/2009 virus. Infections were done at 10^5 PFU or time-matched mock infected. Time points were 2 and 4 d.p.i. There were 2-3 animals/dose/time point. Lung samples were collected for virus load and transcriptional analysis. Weight loss and animal survival were also monitored.
Project description:Here, we characterize RIPK3-dependent transcriptional responses in cortical neurons following infection with neurotropic flaviviruses. Neurons were infected with either Zika virus (ZIKV) strain MR766 at an MOI of 0.1, West Nile virus (WNV) strain TX 2002-HC at an MOI of 0.001, or a saline mock solution. Neurons were derived from mice lacking RIPK3 expression (Ripk3-/-) or wildtype controls. These studies revealed a number of antiviral genes whose upregulation following viral infection is absent in neurons lacking RIPK3, a subset of which were validated using qRT-PCR.
Project description:Ripk3-deficient fibroblasts and lung epithelial cells are resistant to influenza-induced cell deaths. However, Ripk3 is required for protection against influenza infection in vivo. Here, we examine the influenza-regulated gene expressions between wild type and knock out MEFs as well as an involvement of kinase activity if any.
Project description:Astrocyte activation is a common feature of neurodegenerative diseases. However, the ways in which dying neurons influence the activity of astrocytes is poorly understood. RIPK3 signaling has recently been described as a key regulator of neuroinflammation, but whether this kinase mediates astrocytic responsiveness to neuronal death has not yet been studied. Here, we used the MPTP model of Parkinson’s disease to show that activation of astrocytic RIPK3 drives dopaminergic cell death and axon damage. Transcriptomic profiling revealed that astrocytic RIPK3 promoted gene expression associated with neuroinflammation and movement disorders, and this coincided with significant engagement of DAMP signaling. Using human cell culture systems, we show that factors released from dying neurons signal through RAGE to induce RIPK3-dependent astrocyte activation. These findings highlight a mechanism of neuron-glia crosstalk in which neuronal death perpetuates further neurodegeneration by engaging inflammatory astrocyte activation via RIPK3.