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Sulfonamide antibiotics (SAs) have been produced and consumed on a large scale over the last few decades. SAs are a typical class of refractory contaminants that are omnipresent in various environments. Although several [phenyl]-SA-degrading bacteria and their corresponding genomes have been documented, limited genetic information is available for the degraders of heterocyclic products (e.g., 3-amino-5-methylisoxazole [3A5MI] produced via sulfamethoxazole [SMX] catabolism). In this study, the previously isolated SMX-mineralizing bacterial partners, Paenarthrobacter sp. P27 (responsible for the initial cleavage of the -C-S-N- bond of SMX and further degradation of [phenyl]-SMX) and Norcardiodes sp. N27 (responsible for 3A5MI catabolism), were further studied and their complete genomes were sequenced. Complete degradation and bacterial growth were verified by pure-culture experiments with SMX or 3A5MI as the sole carbon, nitrogen, and energy source. By cross-feeding strains P27 and N27, complete catabolism of SMX could be achieved over a wide range of initial SMX concentrations. Moreover, strain P27 was capable of transforming the additional nine SA representatives into their corresponding nitrogen-containing heterocyclic products, strongly indicating the broad substrate spectrum and marked bioremediation potential of strain P27. The genome of strain P27 contained the highly homologous monooxygenase gene cluster, sadABC, which initially attacked the sulfonamide molecules. The complete genome sequences of the two important degraders will benefit future research centering on the molecular mechanism underlying advanced SMX mineralization and will aid in further understanding the interspecific interactions and metabolite exchanges for the optimization of artificially constructed synthetic functional microbiomes.Excessive bone erosion by osteoclasts is associated with osteoporosis, rheumatoid arthritis, and periprosthetic osteolysis. Targeting osteoclasts may serve as an effective treatment for osteolytic diseases. Although drugs are currently available for the treatment of these diseases, exploring potential anti-osteoclast natural compounds with safe and effective treatment remains needed. Oroxylin A (OA), a natural flavonoid isolated from the root of Scutellaria baicalensis Georgi, has numerous beneficial pharmacological characteristics, including anti-inflammatory and antioxidant activity. However, its effects and mechanisms on osteoclast formation and bone resorption have not yet been clarified. Our research showed that OA attenuated the formation and function of osteoclast induced by RANKL in a time- and concentration-dependent manner without any cytotoxicity. Mechanistically, OA suppressed intracellular reactive oxygen species (ROS) levels through the Nrf2-mediated antioxidant response. Moreover, OA inhibited the activity of NFATc1, the master transcriptional regulator of RANKL-induced osteoclastogenesis. OA exhibited protective effects in mouse models of post-ovariectomy (OVX)- and lipopolysaccharide (LPS)-induced bone loss, in accordance with its in vitro anti-osteoclastogenic effect. Collectively, our findings highlight the potential of OA as a pharmacological agent for the prevention of osteoclast-mediated osteolytic diseases.The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway is characterized by diverse immune regulatory systems involving cell proliferation, survival, and inflammation and immune tolerance. Aberrant JAK/STAT transduction activates proinflammatory cytokine signaling that jeopardize the immune balance and thus contributes to the development of autoimmune diseases and cancer progression. The success of several small-molecule JAK inhibitors in the treatment of rheumatologic diseases demonstrates that targeting the JAK/STAT pathway is efficient in suppressing inflammation and sheds light on their therapeutic potential in several autoimmune diseases and cancers. In this review, we discuss the signal transduction and molecular mechanism involving immune function through the JAK-STAT pathway, outline the role of this pathway in autoimmunity and oncoimmunology, and explain the preclinical and clinical trial evidence for the therapeutic potential of targeting the JAK-STAT signaling pathway. Issues regarding the safety and clinical efficacy of JAK inhibitors are reviewed. Ongoing studies are addressed with a focus on emerging indications for JAK inhibition and explanations of the novel mechanisms of JAK-STAT signaling blockade.

Endoscopic differential diagnoses of gastric mucosal lesions (benign gastric ulcer, early gastric cancer [EGC], and advanced gastric cancer) remain challenging. We aimed to develop and validate convolutional neural network-based artificial intelligence (AI) models lesion detection (AI-LD), differential diagnosis (AI-DDx), and invasion-depth (AI-ID, pT1a vs. pT1b among EGC) models.

This study included 1,366 consecutive patients with gastric mucosal lesions from 2 referral centers in Korea. RNA Synthesis inhibitor One representative endoscopic image from each patient was used. Histological diagnoses were set as the criterion standard. The performances of the AI-DDx (training/internal/external validation set, n=1009/112/245) and AI-ID (training/internal/external validation set, n=620/68/155) were compared with visual diagnoses by independent endoscopists (stratified by novice [<1 year of experience], intermediate [2-3 years of experience], and expert [>5 years of experience]) and endoscopic ultrasonography (EUS) results, respe differential diagnosis of gastric mucosal lesion. The AI-ID performed better than EUS for the invasion-depth evaluation (https//aiscopeseoul.com/).Histone arginine methylation is a key post-translational modification that mediates epigenetic events that activate or repress gene transcription. Protein arginine methyltransferases (PRMTs) are the driving force for the process of arginine methylation, and the core histone proteins have been shown to be substrates for most PRMT family members. However, previous reports of the enzymatic activities of PRMTs on histones in the context of nucleosomes seem contradictory. Moreover, what governs nucleosomal substrate recognition of different PRMT members is not understood. We sought to address this key biological question by examining how different macromolecular contexts where the core histones reside may regulate arginine methylation catalyzed by individual PRMT members (i.e., PRMT1, -3, -4, -5, -6, -7, and -8). Our results demonstrated the substrate context exhibits a huge impact on the histone arginine methylation activity of PRMTs. Although all the tested PRMTs methylate multiple free histones individually, they show a preference for one particular histone substrate in the context of the histone octamer. We found that PRMT1, -3, -5, -6, -7, and -8 preferentially methylate histone H4, while PRMT4/CARM1 prefers histone H3. Importantly, neither reconstituted nor cell-extracted mononucleosomes could be methylated by any PRMTs tested. Structural analysis suggested that the electrostatic interaction may play a mechanistic role in priming the substrates for methylation by PRMT enzymes. Taken together, this work expands our knowledge on the molecular mechanisms of PRMT substrate recognition and has important implications for understanding cellular dynamics and kinetics of histone arginine methylation in regulating gene transcription and other chromatin-templated processes.The yeast endoplasmic reticulum has three distinct protein translocation channels. The heterotrimeric Sec61 and Ssh1 complexes, which bind translating ribosomes, mediate cotranslational translocation of proteins targeted to the endoplasmic reticulum by the signal recognition particle (SRP) and SRP receptor targeting pathway, whereas the heptameric Sec complex has been proposed to mediate ribosome-independent posttranslational translocation of proteins with less hydrophobic signal sequences that escape recognition by the SRP. However, multiple reports have proposed that the Sec complex may function cotranslationally and be involved in translocation or integration of SRP-dependent protein translocation substrates. To provide insight into these conflicting views, we induced expression of the tobacco etch virus (TEV) protease to achieve rapid inactivation of the Sec complex by protease-mediated cleavage within the cytoplasmic domain of the Sec63 protein. Protein translocation assays conducted after TEV protease induction revealed a complete block in translocation of two well-characterized substrates of the Sec complex, carboxypeptidase Y (CPY) and Gas1p, when the protease cleavage sites were located at structural domain boundaries in Sec63. However, integration of SRP-dependent membrane protein substrates was not detectably impacted. Moreover, redirecting CPY to the cotranslational pathway by increasing the hydrophobicity of the signal sequence rendered translocation of CPY insensitive to inactivation of the Sec complex. We conclude that the Sec complex is primarily responsible for the translocation of yeast secretome proteins with marginally hydrophobic signal sequences.Elevated intracellular levels of deoxy-nucleotide triphosphates (dNTPs) have been shown to be a biochemical marker of cancer cells. Recently, a series of mutations in the multi-functional dNTPase, SAMHD1, have been reported in various cancers. Here we investigated the structure and functions of SAMHD1 R366C/H mutants, found in colon cancer and leukemia. Unlike many other cancer-specific mutations, the SAMHD1 R366 mutations do not alter cellular protein levels of the enzyme. However, R366C/H mutant proteins exhibit a loss of dNTPase activity and their X-ray structures demonstrate the absence of dGTP substrate in their active site, likely due to loss of interaction with γ-phosphate of the substrate. The R366C/H mutants failed to reduce intracellular dNTP levels and restrict HIV-1 replication, functions of SAMHD1 that are dependent on the ability of the enzyme to hydrolyze dNTPs. However, these mutants retain dNTPase-independent functions, including mediating double-stranded DNA break repair, interacting with CtIP and Cyclin A2, and suppressing innate immune responses. Finally, SAMHD1 degradation in human primary activated/dividing CD4+ T cells further elevates cellular dNTP levels. This study suggests that the loss of SAMHD1 dNTPase activity induced by R366 mutations can mechanistically contribute to the elevated dNTP levels commonly found in cancer cells.Recent studies have revealed that the effects of estrogen deficiency are not restricted to osteoclasts and bone resorption, but that bone matrix composition is altered and osteoblasts exhibit an impaired response to mechanical stimulation. In this study, we test the hypothesis that estrogen depletion alters osteogenic differentiation and matrix production by mechanically stimulated osteoblasts in vitro. MC3T3-E1 cells were pre-treated with estrogen for 14 days, after which estrogen was withdrawn or inhibited with Fulvestrant up to 14 days. Fluid shear stress (FSS) was applied using an orbital shaker. Under estrogen depletion in static culture, osteogenic marker (ALP) and gene expression (Runx2) were decreased at 2 and after 7 days of estrogen depletion, respectively. In addition, up to 7 day the inhibition of the estrogen receptor significantly decreased fibronectin expression (FN1) under static conditions. Under estrogen depletion and daily mechanical stimulation, changes in expression of Runx2 occurred earlier (4 days) and by 14 days, changes in matrix production (Col1a1) were reported.