149 research outputs found
Discovery of a Selective, Substrate-Competitive Inhibitor of the Lysine Methyltransferase SETD8
The lysine methyltransferase SETD8 is the only known methyltransferase that catalyzes monomethylation of histone H4 lysine 20 (H4K20). Monomethylation of H4K20 has been implicated in regulating diverse biological processes including the DNA damage response. In addition to H4K20, SETD8 monomethylates non-histone substrates including proliferating cell nuclear antigen (PCNA) and promotes carcinogenesis by deregulating PCNA expression. However, selective inhibitors of SETD8 are scarce. The only known selective inhibitor of SETD8 to date is nahuoic acid A, a marine natural product, which is competitive with the cofactor. Here, we report the discovery of the first substrate-competitive inhibitor of SETD8, UNC0379 (1). This small-molecule inhibitor is active in multiple biochemical assays. Its affinity to SETD8 was confirmed by ITC (isothermal titration calorimetry) and SPR (surface plasmon resonance) studies. Importantly, compound 1 is selective for SETD8 over 15 other methyltransferases. We also describe structure–activity relationships (SAR) of this series
The Lipid Kinase PIP5K1C Regulates Pain Signaling and Sensitization
SummaryNumerous pain-producing (pronociceptive) receptors signal via phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis. However, it is currently unknown which lipid kinases generate PIP2 in nociceptive dorsal root ganglia (DRG) neurons and if these kinases regulate pronociceptive receptor signaling. Here, we found that phosphatidylinositol 4-phosphate 5 kinase type 1C (PIP5K1C) is expressed at higher levels than any other PIP5K and, based on experiments with Pip5k1c+/− mice, generates at least half of all PIP2 in DRG neurons. Additionally, Pip5k1c haploinsufficiency reduces pronociceptive receptor signaling and TRPV1 sensitization in DRG neurons as well as thermal and mechanical hypersensitivity in mouse models of chronic pain. We identified a small molecule inhibitor of PIP5K1C (UNC3230) in a high-throughput screen. UNC3230 lowered PIP2 levels in DRG neurons and attenuated hypersensitivity when administered intrathecally or into the hindpaw. Our studies reveal that PIP5K1C regulates PIP2-dependent nociceptive signaling and suggest that PIP5K1C is a therapeutic target for chronic pain
Heterologous expression of the Haynaldia villosa pattern-recognition receptor CERK1-V in wheat increases resistance to three fungal diseases
Wheat production is under continuous threat by various fungal pathogens. Identification of multiple-disease resistance genes may lead to effective disease control via the development of cultivars with broad-spectrum resistance. Plant Lysin-motif (LysM)-type pattern-recognition receptors, which elicit innate immunity by recognizing fungal pathogen associated molecular patterns such as chitin, are potential candidates for such resistance. In this study, we cloned a LysM receptor-like kinase gene, CERK1-V, from the diploid wheat relative Haynaldia villosa. CERK1-V expression was induced by chitin and Blumeria graminis f. sp. tritici, the causal agent of wheat powdery mildew. Heterologous overexpression of CERK1-V in wheat inhibited the development of three fungal pathogens, thereby increased resistance to powdery mildew, yellow rust, and Fusarium head blight. CERK1-V physically interacted with the wheat LysM protein TaCEBiPs. CERK1-V/TaCEBiPs interaction promoted chitin recognition and activated chitin signal transduction in wheat. Transgenic plants with excessively high CERK1-V expression showed high resistance but abnormal plant growth, whereas plants with moderate expression level showed adequate resistance level with no marked impairment of plant growth. In transgenic lines, RNA-seq showed that gene expression involved in plant innate immunity was activated. Expression of genes involved in photosynthesis, ER stress and multiple phytohormone pathways was also activated. Optimized expression of CERK1-V in wheat can confer disease resistance without compromising growth or defense fitness
Modelling underground coal gasification: What to start with
Underground coal gasification (UCG) is widely regarded as a clean coal technology that holds enormous potential to decarbonize the world's coal industry. It converts coal underground into combustible syngas through a set of complex physiochemical events. Experimental and numerical efforts over the past century have contributed to the development of UCG around the world; however, tapping the world's deep-situated coal resources with UCG requires substantial contributions from numerous high-quality researchers. To facilitate effective engagement, this paper will provide a background on where to start if one wishes to undertake UCG modelling. First, a brief description of the fundamental phenomena involved in UCG is given. Then, a succinct introduction of the widely used modelling software is rendered, followed by a description of UCG studies to provide insight how to tune the various software packages for modelling UCG and where their strengths lie. This paper shall serve as guidance to new UCG modellers
Microfluidic Assaying of Circulating Tumor Cells and Its Application in Risk Stratification of Urothelial Bladder Cancer
Bladder cancer is characterized by its frequent recurrence and progression. Effective treatment strategies need to be based on an accurate risk stratification, in which muscle invasiveness and tumor grade represent the two most important factors. Traditional imaging techniques provide preliminary information about muscle invasiveness but are lacking in terms of accuracy. Although as the gold standard, pathological biopsy is only available after the surgery and cannot be performed longitudinally for long-term surveillance. In this work, we developed a microfluidic approach that interrogates circulating tumor cells (CTCs) in the peripheral blood of bladder cancer patients to reflect the risk stratification of the disease. In a cohort of 48 bladder cancer patients comprising 33 non-muscle invasive bladder cancer (NMIBC) cases and 15 muscle invasive bladder cancer (MIBC) cases, the CTC count was found to be considerably higher in the MIBC group compared with the NMIBC group (4.67 vs. 1.88 CTCs/3 mL, P=0.019), and was significantly higher in high-grade bladder cancer patients verses low-grade bladder cancer patients (3.69 vs. 1.18 CTCs/3mL, P=0.024). This microfluidic assay of CTCs is believed to be a promising complementary tool for the risk stratification of bladder cancer
Probiotics fortify intestinal barrier function: a systematic review and meta-analysis of randomized trials
BackgroundProbiotics play a vital role in treating immune and inflammatory diseases by improving intestinal barrier function; however, a comprehensive evaluation is missing. The present study aimed to explore the impact of probiotics on the intestinal barrier and related immune function, inflammation, and microbiota composition. A systematic review and meta-analyses were conducted.MethodsFour major databases (PubMed, Science Citation Index Expanded, CENTRAL, and Embase) were thoroughly searched. Weighted mean differences were calculated for continuous outcomes with corresponding 95% confidence intervals (CIs), heterogeneity among studies was evaluated utilizing I2 statistic (Chi-Square test), and data were pooled using random effects meta-analyses.ResultsMeta-analysis of data from a total of 26 RCTs (n = 1891) indicated that probiotics significantly improved gut barrier function measured by levels of TER (MD, 5.27, 95% CI, 3.82 to 6.72, P < 0.00001), serum zonulin (SMD, -1.58, 95% CI, -2.49 to -0.66, P = 0.0007), endotoxin (SMD, -3.20, 95% CI, -5.41 to -0.98, P = 0.005), and LPS (SMD, -0.47, 95% CI, -0.85 to -0.09, P = 0.02). Furthermore, probiotic groups demonstrated better efficacy over control groups in reducing inflammatory factors, including CRP, TNF-α, and IL-6. Probiotics can also modulate the gut microbiota structure by boosting the enrichment of Bifidobacterium and Lactobacillus.ConclusionThe present work revealed that probiotics could improve intestinal barrier function, and alleviate inflammation and microbial dysbiosis. Further high-quality RCTs are warranted to achieve a more definitive conclusion.Clinical trial registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=281822, identifier CRD42021281822
Exploiting an Allosteric Binding Site of PRMT3 Yields Potent and Selective Inhibitors
Protein arginine methyltransferases (PRMTs) play an important role in diverse biological processes. Among the nine known human PRMTs, PRMT3 has been implicated in ribosomal biosynthesis via asymmetric dimethylation of the 40S ribosomal protein S2 and in cancer via interaction with the DAL-1 tumor suppressor protein. However, few selective inhibitors of PRMTs have been discovered. We recently disclosed the first selective PRMT3 inhibitor, which occupies a novel allosteric binding site and is noncompetitive with both the peptide substrate and cofactor. Here we report comprehensive structure-activity relationship studies of this series, which resulted in the discovery of multiple PRMT3 inhibitors with submicromolar potencies. An X-ray crystal structure of compound 14u in complex with PRMT3 confirmed that this inhibitor occupied the same allosteric binding site as our initial lead compound. These studies provide the first experimental evidence that potent and selective inhibitors can be created by exploiting the allosteric binding site of PRMT3
Female Membership in the Black-Society Style Criminal Organizations: Evidence From a Female Prison in China
From the 1970s onwards, women’s participation in gangs in the mainstream Western social contexts has been increasingly researched. However, the experiences of women in other cultural settings are rarely discussed. This qualitative study focuses on female members of the black-society style criminal organizations (BSSCO) in China. It starts with reviewing literature on female gang membership and on BSSCO so as to locate its discussions in the international criminological framework. This is followed by a methodology section, and then it analyses the empirical findings. This article seeks to provide some theoretical insights into the construction of female criminal membership in broader social contexts
The dynamic conformational landscape of the protein methyltransferase SETD8
Elucidating the conformational heterogeneity of proteins is essential for understanding
protein function and developing exogenous ligands. With the rapid development of experimental
and computational methods, it is of great interest to integrate these approaches to illuminate the
conformational landscapes of target proteins. SETD8 is a protein lysine methyltransferase (PKMT),
which functions in vivo via the methylation of histone and nonhistone targets. Utilizing covalent
inhibitors and depleting native ligands to trap hidden conformational states, we obtained diverse
X-ray structures of SETD8. These structures were used to seed distributed atomistic molecular
dynamics simulations that generated a total of six milliseconds of trajectory data. Markov state
models, built via an automated machine learning approach and corroborated experimentally, reveal
how slow conformational motions and conformational states are relevant to catalysis. These
findings provide molecular insight on enzymatic catalysis and allosteric mechanisms of a PKMT via
its detailed conformational landscape
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