Project description:Activation of the NACHT, LRR family pyrin domain containing 3 (NLRP3) inflammasome complex is an essential innate immune signalling mechanism. To reveal how NLRP3 inflammasome assembly and activation are controlled, in particular by components of the ubiquitin system, proximity labelling, affinity purification and RNAi screening approaches were performed. Our study provides an intricate time-resolved molecular map of different phases of NLRP3 inflammasome activation. We discovered that ubiquitin C-terminal hydrolase 1 (UCH-L1) interacts with the NACHT domain of NLRP3, and downregulation of UCH-L1 decreases pro-IL-1β levels. UCH-L1 chemical inhibition with small molecules interfered with NLRP3 puncta formation and ASC oligomerisation, leading to altered IL-1β cleavage and secretion, particularly in microglia cells, which exhibited elevated UCH-L1 expression as compared to monocytes/macrophages. Altogether, we profiled NLRP3 inflammasome activation dynamics and highlight UCH-L1 as an important modulator of NLRP3-mediated IL-1β production, suggesting that a pharmacological inhibitor of UCH-L1 may decrease inflammation-associated pathologies.
Project description:Antibodies and derivative drugs targeting immune checkpoints have been approved for the treatment of several malignancies, but there are fewer responses in patients with pancreatic cancer. Here, we designed a nanobody molecule with bi-targeting on PD-L1 and CXCR4, as both targets are overexpressed in many cancer cells and play important roles in tumorigenesis. The nanobody sequences targeting PD-L1 and CXCR4 were linked by the (G4S)3 flexible peptide to construct the anti-PD-L1/CXCR4 bispecific nanobody. The bispecific nanobody was expressed in E. coli cells and purified by affinity chromatography. The purified nanobody was biochemically characterized by mass spectrometry, Western blotting and flow cytometry to confirm the molecule and its association with both PD-L1 and CXCR4. The biological function of the nanobody and its anti-tumour effects were examined.
Project description:Somatic L1 retrotransposition events have been shown to occur in epithelial cancers1-8. Here, we attempted to determine how early somatic L1 insertions occurred during the development of gastrointestinal (GI) cancers. Using L1-targeted resequencing (L1-seq), we studied different stages of four colorectal cancers arising from colonic polyps, seven pancreatic carcinomas, as well as seven gastric cancers. Surprisingly, we found somatic L1 insertions not only in all cancer types and metastases, but also in colonic adenomas, well-known cancer precursors. Some insertions were also present in low quantities in normal GI tissues, occasionally caught in the act of being clonally fixed in the adjacent tumors. Insertions in adenomas and cancers numbered in the hundreds and many were present in multiple tumor sections implying clonal distribution. Our results demonstrate that extensive somatic insertional mutagenesis occurs very early during the development of GI tumors, probably before dysplastic growth. We assessed the impact of somatic L1 insertions on the expression of the corresponding protein-coding genes by comparing protein abundance in the polyp with the highest number of somatic L1 insertions with that of its paired normal colon using mass spectrometry analysis. Of the 10 validated somatic insertions that were in protein coding regions in the polyp, two proteins – KIAA1217 and WARS2 – were downregulated in the adenoma >90% and >70%, respectively.
Project description:Insulin is a potent regulator of protein metabolism. Here we describe a time-resolved map of insulin-regulated protein turnover in 3T3-L1 adipocytes using metabolic pulse-chase labelling and high-resolution mass spectrometry.
Project description:We performed proteomics analysis to discover effector proteins for the post-transcriptional regulation of PD-L1 onhuman macrophages stimulated by adenosine signal.
Project description:We analyzed RING1B binding regions in 3T3-L1 cell lines transduced with the retroviral vector for V5-tagged Fbxl10 or its dF-box mutant. RING1B ChIP-seq in empty, Fbxl10-1, and dF-box mutant vector transduced 3T3-L1 preadipocytes, in duplicate, and V5-Fbxl10 ChIP-seq in Fbxl10 overexpressing 3T3-L1 cells
Project description:Obesity is often associated with a low-grade systemic inflammation state that contributes to the development of insulin resistance and atherosclerotic complications. This is usually coupled with increased macrophage infiltration in the adipose tissue and a defect in adipocyte differentiation that results in accumulation of hypertrophic fat cells characterized by a deregulated pattern of adipokine expression. Here we show that knockdown of histone demethylase lsd1 in 3T3-L1 preadipocytes results in defective adipogenesis and derepression of an inflammatory program in these cells. The dataset consists of four sample groups: [1] 3T3-L1 preadipocytes (passage 19) transfected with a control scrambled siRNA at 24h after transfection (siC.24h), [2] 3T3-L1 preadipocytes (p.19) transfected with a siRNA directed against LSD1 at 24h after transfection (siLsd1.24h), [3] 3T3-L1 preadipocytes (p.21) transfected with a control scrambled siRNA at 48h after transfection (siC.48h), and [4] 3T3-L1 preadipocytes (p.21) transfected with a siRNA directed against LSD1 at 48h after transfection (siLsd1.48h). The 24h sample groups (siC.24h and siLsd1.24h) consist of two biological replicate samples; the 48h sample groups (siC.48h and siLsd1.48h) consist of three biological replicate samples. Each sample was hybridized to a separate array, for a total of ten arrays.