Dexmedetomidine Inhibits NF-κB-Transcriptional Activity in Neurons Undergoing Ischemia-Reperfusion by Regulating O-GlcNAcylation of SNW1

Dexmedetomidine (Dex) is neuroprotective in ischemia-reperfusion (I/R) by suppressing inflammation but the underlying molecular mechanisms are not known. SNW domain-containing protein 1 (SNW1) is a coactivator of the pro-inflammatory transcription factor NF-κB p65. Because SNW1 is regulated by O-GlcNAcylation, we aimed to determine whether this modification influences NF-κB transcriptional activity in neurons undergoing I/R and how Dex may affect the O-GlcNAcylation of SNW1. SH-SY5Y and PC12 cells under hypoxia/reoxygenation (H/R) conditions were treated with Dex and with inhibitors of O-GlcNAc transferase (OGT). O-GlcNAc levels in SNW1 and effects of SNW1 on NF-κB p65 were determined by immunoprecipitation. H/R increased SNW1 protein levels but inhibited O-GlcNAcylation of SNW1. A Luciferase reporter assay demonstrated that increased SNW1 levels led to increased NF-κB p65 activity and increased secretion of neuron-derived inflammatory factors demonstrated by ELISA. Dex reversed the H/R-induced increase of SNW1 protein by upregulating OGT and enhancing O-GlcNAcylation of SNW1. Dex suppression of the SNW1/NF-κB complex resulted in neuroprotection in vitro and in a middle cerebral artery occlusion model in vivo. PKA and ERK1/2 inhibitors abolished the effect of Dex on OGT protein. Taken together, these data indicate that Dex inhibits NF-κB-transcriptional activity in neurons undergoing I/R by regulating O-GlcNAcylation of SNW1.

Protein network analysis to prioritize key genes in amyotrophic lateral sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a fatal disease, progressive nature characterizes by loss of both upper and lower motor neuron functions. One of the major challenge is to understand the mechanism of ALS multifactorial nature. We aimed to explore some key genes related to ALS through bioinformatics methods for its therapeutic intervention. Here, we applied a systems biology approach involving experimentally validated 148 ALS-associated proteins and construct ALS protein-protein interaction network (ALS-PPIN). The network was further statistically analysed and identified bottleneck-hubs. The network is also subjected to identify modules which could have similar functions. The interaction between the modules and bottleneck-hubs provides the functional regulatory role of the ALS mechanism. The ALS-PPIN demonstrated a hierarchical scale-free nature. We identified 17 bottleneck-hubs, in which CDC5L, SNW1, TP53, SOD1, and VCP were the high degree nodes (hubs) in ALS-PPIN. CDC5L was found to control highly cluster modules and play a vital role in the stability of the overall network followed by SNW1, TP53, SOD1, and VCP. HSPA5 and HSPA8 acting as a common connector for CDC5L and TP53 bottleneck-hubs. The functional and disease association analysis showed ALS has a strong correlation with mRNA processing, protein deubiquitination, and neoplasms, nervous system, immune system disease classes. In the future, biochemical investigation of the observed bottleneck-hubs and their interacting partners could provide a further understanding of their role in the pathophysiology of ALS.

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Amyotrophic Lateral Sclerosis protein-protein interaction network (ALS-PPIN) followed a hierarchical scale-free nature.

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We identified 17 bottleneck-hubs in the ALS-PPIN.

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Among bottleneck-hubs we found CDC5L, SNW1, TP53, SOD1, and VCP were the high degree nodes (hubs) in the ALS-PPIN.

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CDC5L is the effective communicator with all five modules in the ALS-PPIN and followed by SNW1 and TP53.

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Modules are highly associated with various disease classes like neoplasms, nervous systems and others.

Binding Nemo

Article highlight based on "SNW1 interacts with IKKγ to positively regulate antiviral innate immune responses against influenza A virus infection" by Qiao et al.

SNW1 is a prognostic biomarker in prostate cancer

Background

SNW1 is a nuclear receptor co-activator involved in splicing and transcription control, including androgen receptor signaling. Overexpression of SNW1 has been linked to adverse prognosis in different cancer types, but studies on the role of SNW1 in prostate cancer are lacking.

Methods

Using immunohistochemistry, we analyzed SNW1 expression in 10,310 prostate cancers in a tissue microarray (TMA) with attached clinical and molecular data.

Results

The comparison with normal prostate tissue revealed an up regulation of SNW1 in a subset of cancer samples. SNW1 staining was considered weak in 31.5%, moderate in 37.7% and strong in 14% of cancers. Strong SNW1 expression was markedly more frequent in prostate cancers harboring the TMPRSS2:ERG fusion (24%) than in ERG negative cancers (7%, p < 0.0001). Significant associations with Gleason grade, stage, nodal status and early biochemical recurrence were observed in the ERG negative and positive subset. Multivariable modeling revealed that the prognostic value of SNW1 up regulation was independent from the established preoperative histopathological and clinical parameters.

Conclusion

These results demonstrate that SNW1 overexpression is an independent prognostic marker in prostate cancer with potential clinical utility.

Electronic supplementary material

The online version of this article (10.1186/s13000-019-0810-8) contains supplementary material, which is available to authorized users.

SNW1 regulates Notch signaling in neuroblastoma through interacting with RBPJ

The Notch signaling pathway is highly conserved, involved in cell-cell communication, and essential for multicellular organism development. The recombination signal binding protein for immunoglobulin kappa J region (RBPJ) transcriptional regulator plays a vital role in Notch signaling. When not complexed with Notch proteins, RBPJ acts as a transcriptional repressor. However, when bound to the Notch intracellular domain (NOTCH ICD) in the nucleus, RBPJ activates the transcription of Notch target genes. However, the role of RBPJ in the Notch signaling pathway in neuroblastoma (NB) remains unclear. In this study, we show that SNW domain containing 1 (SNW1) acts as a novel RBPJ partner and regulates the expression of Notch target genes. Additionally, we show that silencing RBPJ expression can prevent SNW1-mediated Notch gene expression. Public datasets and clinical NB tissues indicate that RBPJ and SNW1 are upregulated in NB, and are associated with unfavorable patient outcomes. Taken together, our results highlight that SNW1 interacts with RBPJ to regulate the Notch signaling pathway and presents a potential therapeutic target for NB.

Inhibition of SNW1 association with spliceosomal proteins promotes apoptosis in breast cancer cells

RNA splicing is a fundamental process for protein synthesis. Recent studies have reported that drugs that inhibit splicing have cytotoxic effects on various tumor cell lines. In this report, we demonstrate that depletion of SNW1, a component of the spliceosome, induces apoptosis in breast cancer cells. Proteomics and biochemical analyses revealed that SNW1 directly associates with other spliceosome components, including EFTUD2 (Snu114) and SNRNP200 (Brr2). The SKIP region of SNW1 interacted with the N-terminus of EFTUD2 as well as two independent regions in the C-terminus of SNRNP200. Similar to SNW1 depletion, knockdown of EFTUD2 increased the numbers of apoptotic cells. Furthermore, we demonstrate that exogenous expression of either the SKIP region of SNW1 or the N-terminus region of EFTUD2 significantly promoted cellular apoptosis. Our results suggest that the inhibition of SNW1 or its associating proteins may be a novel therapeutic strategy for cancer treatment.