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The Pim (proviral integration site for Moloney murine leukemia virus) proteins compose a serine threonine kinase family whose members regulate cell proliferation, migration and cell survival. However, whether Pim kinases participate in innate immune responses is unclear. Here, we show for the first time that Pim1 plays an essential role in the production of interferon (IFN)-β by macrophages after their Toll-like receptor (TLR) pathway is activated by pathogen-associated molecular patterns (PAMPs). Specifically, Pim1 was quickly upregulated in an NF-κB-dependent manner after TLR stimulation with PAMPs. Pim1 deficiency reduced TLR3- or TLR4-stimulated IFN-β and IFN-stimulated gene (ISG) expression but not proinflammatory cytokine expression in macrophages. Mechanistically, Pim1 specifically upregulates IRF3 phosphorylation and nuclear translocation. However, this role is not dependent on Pim1 kinase activity. Rather, Pim1 appears to promote IRF3 phosphorylation by enhancing the formation of IFN-β signaling complexes composed of TRIF, TRAF3, TBK1, and IRF3. Poly (I:C)-treated Pim1−/− mice produced less serum IFN-β and were less likely to survive than wild-type mice. These findings show for the first time that Pim1 participates in TLR-mediated IFN-β production, thus revealing a novel target for controlling antiviral innate immune responses.

Despite the high prevalence of osteoarthritis (OA) in older populations, disease-modifying OA drugs (DMOADs) are still lacking. This study was performed to investigate the effects and mechanisms of the small molecular drug salicin (SA) on OA progression. Primary rat chondrocytes were stimulated with TNF-α and treated with or without SA. Inflammatory factors, cartilage matrix degeneration markers, and cell proliferation and apoptosis markers were detected at the mRNA and protein levels. Cell proliferation and apoptosis were evaluated by EdU assays or flow cytometric analysis. RNA sequencing, molecular docking and drug affinity-responsive target stability analyses were used to clarify the mechanisms. The rat OA model was used to evaluate the effect of intra-articular injection of SA on OA progression. We found that SA rescued TNF-α-induced degeneration of the cartilage matrix, inhibition of chondrocyte proliferation, and promotion of chondrocyte apoptosis. Mechanistically, SA directly binds to IRE1α and occupies the IRE1α phosphorylation site, preventing IRE1α phosphorylation and regulating IRE1α-mediated endoplasmic reticulum (ER) stress by IRE1α-IκBα-p65 signaling. Finally, intra-articular injection of SA-loaded lactic-co-glycolic acid (PLGA) ameliorated OA progression by inhibiting IRE1α-mediated ER stress in the OA model. In conclusion, SA alleviates OA by directly binding to the ER stress regulator IRE1α and inhibits IRE1α-mediated ER stress via IRE1α-IκBα-p65 signaling. Topical use of the small molecular drug SA shows potential to modify OA progression.

Serine/threonine protein kinases (STKs) are important for signal transduction and involved in multiple physiological processes, including cell growth, central metabolism, and sporulation in bacteria. However, the role of STKs in solventogenic clostridia remains unclear. Here, we identified and comprehensively investigated six STK candidates in Clostridium beijerinckii. These STKs were classified into four groups with distinct characteristics via analysis of genetic organizations, prediction of protein domains, and multiple sequence alignment. Cbei0566 is a member of the PrkA family with 41% identity to PrkA from Bacillus subtilis, and both Cbei0666 and Cbei0813 are two-component-like STKs. Cbei1151 and Cbei1929 belong to the Hanks family STKs and consist of a cytoplasmic catalytic domain, a transmembrane region, and extracellular sensor domains. In-frame deletion mutants of cbei0566, cbei0666, cbei1929, and cbei2661 displayed similar cell growth with wild type. Both Δcbei0666 and Δcbei2661 improved acetone-butanol-ethanol (ABE) production by 14.3% (19.2 g/L vs. 16.8 g/L), and the sporulation frequencies of Δcbei0566, Δcbei1929, and Δcbei2661 significantly decreased to 35.5%, 55.1% and 44.8%, respectively. The restored phenotypes after genetic complementation demonstrated their direct link to STKs deletion. Remarkably, overexpressing cbei0566 contributed to 41.5% more spore formation and cbei1929 overexpression enhanced ABE production from 19.3 to 24.2 g/L, along with 25% less acids. These results revealed that Cbei0566 and Cbei1929 had prominent regulatory functions. This study expands the current knowledge of the existence and functions of STKs in prokaryotes and highlights the importance of STK-mediated signaling networks in developing superior strains. KEY POINTS: • First reported serine/threonine protein kinases in solventogenic clostridia • Six STKs with distinct properties possessed diverse functions in C. beijerinckii • Cbei1929 and Cbei0566 remarkably regulated solventogenesis and sporulation.

Gastric cancer is one of the most lethal human malignancies in the world. Although great efforts are put in developing novel therapeutic targets, the effective targeting drugs are still limited. Recent studies reveal the abnormality of Hippo/YAP axis play critical role in the oncogenic process of gastric cancer. It is of great importance to demonstrate the regulation of Hippo signaling activity and YAP protein turnover in gastric cancer. Besides, the phosphorylation cascade on YAP function, which has been thoroughly investigated, the ubiquitination of YAP is also important in Hippo signaling status. Here, We utilized the DUB (Deubiquitinase) siRNA library to identify critical DUB for Hippo signaling. We discovered OTUB1 as a critical factor to facilitate gastric cancer cell stemness and progression, which deubiquitinated and stabilized YAP protein. The clinical data analysis implicated OTUB1 was higher expressed in gastric cancer, which correlated with YAP activity and poor survival. OUTB1 interacted with YAP protein via its OTU domain (Ovarian tumor domain) and deubiquitinated YAP at several lysine sites (K90, K280, K343, K494 and K497), which subsequently inhibited YAP degradation. Our study revealed a novel deubiquitinase of Hippo/YAP axis and one possible therapeutic target for YAP-driven gastric cancer.

Stimulator of interferon genes (STING) functions downstream of cyclic GMP-AMP synthase in DNA sensing or as a direct receptor for bacterial cyclic dinucleotides and small molecules to activate immunity during infection, cancer and immunotherapy1–10. Precise regulation of STING is essential to ensure balanced immune responses and prevent detrimental autoinflammation11–16. After activation, STING, a transmembrane protein, traffics from the endoplasmic reticulum to the Golgi, where its phosphorylation by the protein kinase TBK1 enables signal transduction17–20. The mechanism that ends STING signalling at the Golgi remains unknown. Here we show that adaptor protein complex 1 (AP-1) controls the termination of STING-dependent immune activation. We find that AP-1 sorts phosphorylated STING into clathrin-coated transport vesicles for delivery to the endolysosomal system, where STING is degraded21. We identify a highly conserved dileucine motif in the cytosolic C-terminal tail (CTT) of STING that, together with TBK1-dependent CTT phosphorylation, dictates the AP-1 engagement of STING. A cryo-electron microscopy structure of AP-1 in complex with phosphorylated STING explains the enhanced recognition of TBK1-activated STING. We show that suppression of AP-1 exacerbates STING-induced immune responses. Our results reveal a structural mechanism of negative regulation of STING and establish that the initiation of signalling is inextricably associated with its termination to enable transient activation of immunity.

Cisplatin, 5FU and docetaxel (TPF) are the most common chemotherapy regimen used for advanced OSCC. However, many cancer patients experience relapse, continued tumor growth, and spread due to drug resistance, which leads to treatment failure and metastatic disease. Here, using a CRISPR/Cas9 based kinome knockout screening, Misshapen-like kinase 1 (MINK1) is identified as an important mediator of 5FU resistance in OSCC. Analysis of clinical samples demonstrated significantly higher MINK1 expression in the tumor tissues of chemotherapy non-responder as compared to chemotherapy responders. The in-vitro and xenograft experiments indicate that knocking out MINK1 restores 5FU mediated cell death in chemoresistant OSCC. An antibody based phosphorylation array screen revealed MINK1 as a negative regulator of p53. Mechanistically, MINK1 modulates AKT phosphorylation at Ser473, which enables p-MDM2 (Ser 166) mediated degradation of p53. We also identified lestaurtinib as a potent inhibitor of MINK1 kinase activity. Lestaurtinib significantly induces 5FU mediated cell death in chemoresistant OSCC lines. The patient derived chemoresistant cell based xenograft data suggest that lestaurtinib restores 5FU sensitivity and facilitates a significant reduction of tumor burden. Overall, our study suggests that MINK1 is a major driver of 5FU resistance in OSCC. The novel combination of MINK1 inhibitor lestaurtinib and 5FU needs further clinical investigation in advanced OSCC. One sentence summary Lestaurtinib reverses 5FU sensitivity in drug resistant OSCC.

Vascular endothelial growth factor A (VEGFA) is a key regulator of angiogenesis, which is a hallmark of cancer that promotes cancer growth and metastasis. It is of great significance to find new intervention targets and related regulatory mechanisms of VEGFA related angiogenesis for the treatment of tumors. This study focuses on the role of tribbles pseudokinase 3 (TRIB3)/signal transducer and activator of transcription 3 (STAT3)/VEGFA signaling axis in colon cancer angiogenesis.This study investigated the expression level of TRIB3 in colon cancer through database analysis and tissue microarray analysis. The effect of TRIB3 on proliferation, migration and tube formation ability of human umbilical vein endothelial cells (HUVECs) was further confirmed by CCK8 assay, scratch-wound assay/migration assay and tube formation assay respectively. The regulatory relationship of TRIB3/VEGFA signaling axis was identified by qPCR and Western blotting, which was further confirmed through animal experiments, and the specific regulatory mechanism was explored by immunoprecipitation (IP) and chromatin immunoprecipitation (ChIP) with colon cancer cell lines.TRIB3 was increased in colon cancer tissues compared to normal tissues, and elevated TRIB3 expression indicated a poor prognosis in colon cancer patients. Moreover, it was found that silencing TRIB3 could inhibit cancer angiogenesis, whereas overexpressing TRIB3 promoted cancer angiogenesis in vitro and in vivo. Mechanistically, TRIB3 physically interacted with STAT3 and enhanced STAT3-mediated transcriptional activity. Furthermore, the function of TRIB3 in cancer angiogenesis was through cooperating with STAT3 to increase the VEGFA expression.Our study provides insights into cancer angiogenesis and offers a potential therapeutic strategy for TRIB3-overexpressed cancer.

Gastric cancer is a heterogeneous disease associated to deregulated gastric epithelia tight junction barrier function and di novo expression of claudin-6; these changes are associated with epithelial-mesenchymal transition, enhanced invasiveness, metastatic progression, resistance to chemotherapy, and poor prognosis. Gastric cancer stem cells represent a rare population of cells within the tumor implicated in tumor growth and higher tumorigenic capacity. The possible relation between claudin-6 expression and the expression of some markers associated to epithelial mesenchymal transition and cancer stem cells in gastric cancer cells have never been explored.CD44, CD24, Twist, Villin, DCLK1, claudin-6, NANOG, E-Cadherin, SOX2, and SNAI1 expression was evaluated by immunofluorescence and cytofluorometry in wild type and Claudin-6 transfected AGS cells. Cell migration assays were also performed. Differentially expressed genes and biological processes analysis was performed to determine gene preponderance. The results showed that claudin-6 overexpression enriched the CD44 + /CD24- subpopulation with an overall increase in the expression and the number of CD44 + cells. A significant increase in NANOG, SOX2 and SNAI1 expression and enhanced cell migration was observed in claudin-6 transfected cells. Transcriptome analysis revealed 271 genes involved in enhanced biological processes with only 31 with a significantly p value; thirteen of those genes are closely associated to epithelial mesenchymal transition processes and folding and unfolding processes of proteins in the endoplasmic reticulum.The pro-tumorigenic effect of claudin-6 in gastric cancer could be associated to dedifferentiation of epithelial cells and an increase in di novo cancer stem cell genesis.

In this study, we investigated whether metabolic dysfunction in women with Polycystic ovarian syndrome (PCOS) induces granulosa cell (GC) stress and activates in the endoplamatic reticulum and the mitochondria (UPRWomen who were diagnosed with PCOS (based on the Rotterdam criteria), were divided into two groups, PCOS with insulin resistance (PCOS-IR; n = 20) and PCOS with no insulin resistance (PCOS-nIR; n = 20), and compared to healthy oocyte donors (CONT; n = 20). Insulin resistance (IR) was assessed on the results of homeostasis model assessment (HOMA) that determines IR using the concentration of fasting plasma glucose and fasting insuline. Expression of UPRWe found that several genes involved in UPROur findings suggest that the GCs of women with PCOS (with or without IR) are metabolically distressed and upregulate UPR

Glaucoma is a common disorder in which the death of retinal ganglion cells (RGCs) results in a progressive loss of sight, even blindness. This study was performed to reveal the key molecular mechanism of RGC damage in glaucoma based on the Gene Expression Omnibus database. Glaucoma-related microarray datasets were identified, followed by collection of differentially expressed genes (DEGs) with the key genes discovered by weighted gene co-expression network analysis. Through LASSO regression analysis, candidate genes involved in the pathogenesis of glaucoma were identified with their accuracy evaluated by receiver operating characteristic curve analysis. The glaucoma-specific transcriptional regulatory network was constructed to determine the key transcription factor regulatory axis. Then, in vitro cell models were established using H

Oral squamous cell carcinoma (OSCC) is a frequently-diagnosed malignancy with high potential for proliferation and invasion. Histone methylation is known as a crucial mechanism that regulates pathological processes in various cancers, including OSCC.This study sought to delve into the molecular mechanism of lysine demethylase 3 A (KDM3A) in OSCC cell proliferation and invasion.Expression levels of KDM3A, lysin-9 of di-methylated histone H3 (H3K9me2), and doublecortin-like kinase 1 (DCLK1) in cells were determined by reverse-transcription quantitative polymerase chain reaction or Western blot analysis. Cell proliferation and invasion were evaluated by cell counting kit-8, colony formation, and Transwell assays. The enrichment of KDM3A and H3K9me2 on the DCLK1 promoter was determined by chromatin immunoprecipitation assay. The functional rescue experiment was performed with DCLK1 overexpression vector and si-KDM3A in CAL-27 and SCC-9 cells.KDM3A was elevated in OSCC cells. KDM3A knockdown suppressed OSCC proliferation and invasion, along with increased H3K9me2 level in OSCC cells. KDM3A and H3K9me2 were enriched on the DCLK1 promoter and inhibiting H3K9me2 improved DCLK1 expression levels. DCLK1 overexpression neutralized the inhibition of KDM3A knockdown on OSCC proliferation and invasion.KDM3A facilitated OSCC proliferation and invasion by eliminating H3K9me2 to upregulate DCLK1 expression levels.

The coordinated metabolism of carbon and nitrogen is essential for optimal plant growth and development. Nitrate is an important molecular signal for plant adaptation to a changing environment, but how nitrate regulates plant growth under carbon deficiency conditions remains unclear. Here we show that the evolutionarily conserved energy sensor SnRK1 negatively regulates the nitrate signalling pathway. Nitrate promoted plant growth and downstream gene expression, but such effects were repressed when plants were grown under carbon deficiency conditions. Mutation of KIN10, the α-catalytic subunit of SnRK1, partially suppressed the inhibitory effects of carbon deficiency on nitrate-mediated plant growth. KIN10 phosphorylated NLP7, the master regulator of the nitrate signalling pathway, to promote its cytoplasmic localization and degradation. Furthermore, nitrate depletion induced KIN10 accumulation, whereas nitrate treatment promoted KIN10 degradation. Such KIN10-mediated NLP7 regulation allows carbon and nitrate availability to control optimal nitrate signalling and ensures the coordination of carbon and nitrogen metabolism in plants.

The intake of dietary protein regulates growth, metabolism, fecundity and lifespan across various species, which makes amino acid (AA)-sensing vital for adaptation to the nutritional environment. The general control nonderepressible 2 (GCN2)-activating transcription factor 4 (ATF4) pathway and the mechanistic target of rapamycin complex 1 (mTORC1) pathway are involved in AA-sensing. However, it is not fully understood which AAs regulate these two pathways in living animals and how they coordinate responses to protein restriction. Here we show in Drosophila that the non-essential AA tyrosine (Tyr) is a nutritional cue in the fat body necessary and sufficient for promoting adaptive responses to a low-protein diet, which entails reduction of protein synthesis and mTORC1 activity and increased food intake. This adaptation is regulated by dietary Tyr through GCN2-independent induction of ATF4 target genes in the fat body. This study identifies the Tyr-ATF4 axis as a regulator of the physiological response to a low-protein diet and sheds light on the essential function of a non-essential nutrient.

Sustained exposure of the lung to various environmental or occupational toxins may eventually lead to pulmonary fibrosis, a devastating disease with no cure. Pulmonary fibrosis is characterized by excessive deposition of extracellular matrix (ECM) proteins such as fibronectin and collagens. The peptidase plasmin degrades the ECM, but protein levels of the plasmin activator inhibitor-1 (PAI-1) are increased in fibrotic lung tissue, thereby dampening plasmin activity. Transforming growth factor-β1 (TGF-β1)-induced activation of SMAD transcription factors promotes ECM deposition by enhancing collagen, fibronectin and PAI-1 levels in pulmonary fibroblasts. Hence, counteracting TGF-β1-induced signaling is a promising approach for the therapy of pulmonary fibrosis. Transient receptor potential cation channel subfamily M Member 7 (TRPM7) supports TGF-β1-promoted SMAD signaling in T-lymphocytes and the progression of fibrosis in kidney and heart. Thus, we investigated possible effects of TRPM7 on plasmin activity, ECM levels and TGF-β1 signaling in primary human pulmonary fibroblasts (pHPF). We found that two structurally unrelated TRPM7 blockers enhanced plasmin activity and reduced fibronectin or PAI-1 protein levels in pHPF under basal conditions. Further, TRPM7 blockade strongly inhibited fibronectin and collagen deposition induced by sustained TGF-β1 stimulation. In line with these data, inhibition of TRPM7 activity diminished TGF-β1-triggered phosphorylation of SMAD-2, SMAD-3/4-dependent reporter activation and PAI-1 mRNA levels. Overall, we uncover TRPM7 as a novel supporter of TGF-β1 signaling in pHPF and propose TRPM7 blockers as new candidates to control excessive ECM levels under pathophysiological conditions conducive to pulmonary fibrosis.

Glucocorticoid receptor (GR) has been implicated in prostate carcinoma growth and progression. Glucocorticoid receptor beta (GRβ) acts as an inhibitor of GR; however, its function is not well understood. Serum- and glucocorticoid-regulated kinase 1 (SGK1) is a GR-responsive gene that phosphorylates N-myc downstream-regulated gene 1 (NDRG1) and is involved in cancer growth and invasion. However, the expression of GR, GRβ, SGK1, and NDRG1 in prostate cancer and their relationship with clinicopathological and functional significance remain unknown. The association between the status of GR, GRβ, SGK1, and NDRG1 immunoreactivity and clinicopathological variables was analyzed in patients with prostate carcinoma to explore their clinical significance. In prostate carcinoma cases, the relative abundance of GR and NDRG1 immunoreactivity was inversely and significantly associated with the primary tumor stage (pT), while GR immunoreactivity was inversely and significantly associated with the Ki-67 score. The relative expression status of NDRG1 was significantly associated with that of GR. However, no significant correlation was observed between any of the clinicopathological parameters and GRβ and SGK1 expression. Our findings indicate that GR and NDRG1 expression status is correlated with clinicopathological features in patients with prostate cancer.

NIMA-related kinase 7 (NEK7) is a serine/threonine kinase, which is the smallest one in mammalian NEK family. At present, many studies have reported that NEK7 has a physiological role in regulating the cell cycle and promoting the mitotic process of cells. In recent years, an increasing number of studies have proposed that NEK7 is involved in the activation of the NLRP3 inflammasome. Under normal conditions, NEK7 is in a low activity state, while under pathological conditions, NEK7 is abnormally expressed and therefore plays a key role in the progression of multiple tumors and chronic inflammatory diseases. This review will concentrate on the mechanism of NEK7 participates in the process of mitosis and regulates the activation of NLRP3 inflammasome, the aberrant expression of NEK7 in a variety of tumors and chronic inflammatory diseases, and some potential inhibitors, which may provide some new ideas for the treatment of diverse tumors and chronic inflammatory diseases associated with NEK7.

FvSnRK2182 is involved in regulating the growth and stress response. SnRK2 family members are positive regulators of downstream signals in the abscisic acid (ABA) signaling pathway, playing key roles in the plant responses to abiotic stresses. Fraxinus velutina Torr. is a candidate phytoremediator of saline-alkali areas, and is a valuable research subject because of its adaptability in saline soil. We identified a SnRK2 gene in F. velutina (named FvSnRK2182), which was significantly upregulated under salt stress. A bioinformatics analysis showed that FvSnRK2182 has a Ser/Thr kinase domain typical of the SnRK2 subfamily. Compared with wild-type (WT) Arabidopsis, its heterologous expression in Arabidopsis resulted in higher auxin content during seed germination and seedling growth, leading to longer primary roots and more lateral roots. The transgenic lines were better able to tolerate treatments with NaCl (100 mM) and/or ABA (0.2 and 0.5 µM), producing a greater biomass than the WT plants. Under NaCl treatment, the shoots of the transgenic lines had lower Na

Enterococcus faecalis, a gram-positive bacterium, is among the most common nosocomial pathogens due to its limited susceptibility to antibiotics and its reservoir of the genes coding for virulence factors. Bacterial enzymes such as kinases and phosphorylases play important roles in diverse functions of a bacterial cell and, thus, are potential antibacterial drug targets. In Gram-positive bacteria, HPr Kinase/Phosphorylase (HPrK/P), a bifunctional enzyme is involved in the regulation of carbon catabolite repression by phosphorylating/dephosphorylating the histidine-containing phosphocarrier protein (HPr) at Ser46 residue. Deficiencies in HPrK/P function leads to severe defects in bacterial growth. This study aimed at identifying novel inhibitors of E. faecalis HPrK/P from a commercial compound library using structure-based virtual screening. The hit molecules were purchased and their effect on enzyme activity and growth of resistant E. faecalis was evaluated in vitro. Furthermore, docking and molecular dynamics simulations were performed to study the interactions of the hit compounds with HPrK/P. Among the identified hit molecules, two compounds inhibited the phosphorylation of HPr as well as significantly reduced the growth of resistant E. faecalis in vitro. These identified potential HPrK/P inhibitors open new research avenues towards the development of novel antimicrobials against resistant Gram-positive bacteria.

The transition from acute kidney injury (AKI) to chronic kidney disease (CKD) is extremely complex. Incomplete renal tubule repair, inflammation, and endoplasmic reticulum (ER) stress all play major roles. AKI activates ER stress, and the sensor protein inositol-requiring kinase-1 (IRE1) mediates inflammation by promoting the phosphorylation of C-jun NH2-terminal kinase (JNK). The interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway is associated with the secretion of renal extracellular matrix (ECM) and fibrosis. It remains unclear whether these signaling pathways play a role in the AKI-CKD transition.In this study, a mouse model of ischemia-reperfusion (I/R) with bilateral renal artery clipping was used. IRE1 or JNK inhibitors were also injected to confirm their roles in the AKI-CKD transition. The renal function of the mice was determined by observing the pathology of the renal tubules and glomeruli through electron microscopy, immunohistochemistry, western blotting and quantitative real-time PCR.I/R stimulates ER stress and the IRE1/JNK pathway in the renal tubules in a short period of time, leading to continuous inflammation. Long-term I/R injury activates the STAT3 pathway in the glomeruli, activates mesangial cells proliferation, causes secretion of large amounts of glomerular ECM, and promotes glomerular sclerosis. This damage to the renal tubules and glomeruli is significantly reduced in I/R model mice pretreated with IRE1 or JNK inhibitors.These findings suggested that the IRE1/JNK pathway regulates the inflammatory cytokines caused by AKI and continues to activate the STAT3 pathway and production of ECM in the glomeruli at late stages, suggesting the feasibility of targeted therapy for the AKI-CKD transition.

Due to the bottlenecks encountered in traditional treatment for tumor, more effective drug targets need to be developed. Cell division cycle 7 kinase plays an important role in DNA replication, DNA repair and recombination signaling pathways. In this review, we first describe recent studies on the role of CDC7 in DNA replication in normal human tissues, and then we integrate new evidence focusing on the important role of CDC7 in replication stress tolerance of tumor cells and its impact on the prognosis of clinical oncology patients. Finally, we comb through the CDC7 inhibitors identified in recent studies as a reference for further research in clinical practice.

Parkinson’s disease (PD) is characterised by selective death of dopaminergic (DA) neurons in the midbrain and motor function impairment. Gastrointestinal issues often precede motor deficits in PD, indicating that the gut-brain axis is involved in the pathogenesis of this disease. The features of PD include both mitochondrial dysfunction and activation of the unfolded protein response (UPR) in the endoplasmic reticulum (ER). PINK1 is a mitochondrial kinase involved in the recycling of defective mitochondria, and PINK1 mutations cause early-onset PD. Like PD patients, pink1 mutant Drosophila show degeneration of DA neurons and intestinal dysfunction. These mutant flies also lack vital proteins due to sustained activation of the kinase R-like endoplasmic reticulum kinase (dPerk), a kinase that induces the UPR. Here, we investigated the role of dPerk in intestinal dysfunction. We showed that intestinal expression of dPerk impairs mitochondrial function, induces cell death, and decreases lifespan. We found that suppressing dPerk in the intestine of pink1-mutant flies rescues intestinal cell death and is neuroprotective. We conclude that in a fly model of PD, blocking gut-brain transmission of UPR-mediated toxicity, is neuroprotective.

Mitotic catastrophe (MC) is a suppressive mechanism that mediates the elimination of mitosis-deficient cells through apoptosis, necrosis or senescence after M phase block. SIRT1 is involved in the regulation of several cellular processes, including autophagy. However, the relationship between SIRT1 and MC has been largely obscure. Our study highlights that SIRT1 might be involved in the regulation of MC. We have shown that degradation of the SIRT1 protein via proteasome and lysosomal pathway was accompanied by MC induced via BMH-21. Overexpression of SIRT1 alleviated MC by decreasing the proportion of apoptotic and multinuclear cells induced by G2/M block and triggered autophagy whereas knockdown of SIRT1 aggravated MC and repressed autophagy. Furthermore, we found that serum starvation triggered autophagy evidently generated lower MC whereas siRNA of ATG5/7 suppressed autophagy leading to higher MC. ChIP analysis revealed that SIRT1 could bind to the promoter of BubR1, a component of spindle assembly checkpoint (SAC), to upregulate its expression. Overexpression of BubR1 decreased MC whereas knockdown of BubR1 increased it. These results reveal that SIRT1 regulates MC through autophagy and BubR1 signaling, and provide evidence for SIRT1, autophagy and BubR1 being the potential cancer therapeutic targets.

β-Glucan is an eco-friendly, biodegradable, and economical biopolymer with important roles for acquiring adaptations to mitigate climate change in crop plants. β-Glucan plays a crucial role in the activation of functional plant innate immune system by triggering the downward signaling cascade/s, resulting in the accumulation of different pathogenesis-related proteins (PR-proteins), reactive oxygen species (ROS), antioxidant defense enzymes, Ca

RIO Kinase 1 (RIOK1) is involved in various pathologies, including cancer. However, the role of RIOK1 in radioresistance of colorectal cancer (CRC) remains largely unknown. In this study, we reported that RIOK1 was overexpressed in rectal cancer tissue with weaker tumor regression after neoadjuvant chemoradiotherapy (neoCRT). Moreover, higher RIOK1 expression predicted a poor prognosis in patients with rectal cancer. Blockade of RIOK1 using Toyocamycin, a pharmacological inhibitor of RIOK1, or by knocking down its expression, decreased the resistance of CRC cells to radiotherapy in vitro and in vivo. A mechanistic study revealed that RIOK1 regulates radioresistance by suppressing the p53 signaling pathway. Furthermore, we found that RIOK1 and Ras-GAP SH3 domain binding protein 2 (G3BP2) interact with each other. RIOK1 phosphorylates G3BP2 at Thr226, which increases the activity of G3BP2. RIOK1-mediated phosphorylation of G3BP2 facilitated ubiquitination of p53 by murine double minute 2 protein (MDM2). Altogether, our study revealed the clinical significance of RIOK1 in CRC, and therapies targeting RIOK1 might alleviate the CRC tumor burden in patients.

Kelch-like protein 3 (KLHL3) is a substrate adaptor of Cullin3-RING ubiquitin ligase (CRL3), and KLHL3-CUL3 complex plays a vital role in the ubiquitination of specific substrates. Mutations and abnormal post-translational modifications of KLHL3-CUL3 affect substrate ubiquitination and may related to the pathogenesis of Gordon syndrome (GS), Primary Hyperparathyroidism (PHPT), Diabetes Mellitus (DM), Congenital Heart Disease (CHD), Pre-eclampsia (PE) and even cancers. Therefore, it is essential to understand the function and molecular mechanisms of KLHL3-CUL3 for the treatment of related diseases. In this review, we summary the structure and function of KLHL3-CUL3, the effect of KLHL3-CUL3 mutations and aberrant modifications in GS, PHPT, DM, CHD and PE. Moreover, we noted a possible role of KLHL3-CUL3 in carcinogenesis and provided ideas for targeting KLHL3-CUL3 for related disease treatment.

Osteoporosis (OP) is a frequent orthopedic disease characterized by pain, fractures and deformities. Glucocorticoids are the most common cause of secondary osteoporosis. Here, we aim to explore the function and mechanism of STK11 in glucocorticoid (GC)-induced OP. Human mesenchymal stromal cells (hMSCs) were differentiated under osteogenic or adipogenic culture medium. An in-vitro OP model was induced by dexamethasone (DEX). The viability, differentiation, apoptosis, and ROS level were evaluated for investigating the functions of SKT11 on hMSCs. The SIRT1 inhibitor EX-527, PGC1α inhibitor SR-18292, and AMPK activator metformin were administered into hMSCs for confirming the mechanism of SKT11. Our results showed that STK11 was down-regulated in OP tissues, as well as DEX-treated hMSCs. Overexpressing STK11 attenuated DEX-mediated inhibition of osteogenic differentiation and heightened the activation of the AMPK/SIRT1/PGC1α pathway, whereas STK11 knockdown exerted opposite effects. Inhibiting SIRT1 or PGC1α repressed the promotive effect of STK11 on osteogenic differentiation of hMSCs, while activation of AMPK abated the inhibitory effect of STK11 knockdown on osteogenic differentiation of hMSCs. In conclusion, this study revealed that overexpressing STK11 dampened GC-induced OP by activating the AMPK/SIRT1/PGC1α axis.

Entry of mammalian cells into DNA synthesis (S-phase) represents a key event in cell division(1). According to the current cell-cycle models, the Cdc7 kinase constitutes an essential and rate-limiting trigger of DNA replication, acting together with cyclin-dependent kinase Cdk2. Here we show, using chemical-genetic systems which allow an acute shutdown of Cdc7 in in vitro cultured cells as well as in vivo in a living mouse, that Cdc7 is dispensable for cell division of many different cell types. We demonstrate that another cell-cycle kinase, Cdk1, is also active during G1/S transition both in cycling cells and in cells exiting quiescence. We show that Cdc7 and Cdk1 play functionally redundant roles during G1/S transition, and at least one of these kinases must be present to allow S-phase entry. These observations revise our understanding of cell-cycle progression by demonstrating that Cdk1 physiologically regulates two distinct transitions during cell division cycle, while Cdc7 plays a redundant function in DNA replication.

The search for potential gene loci that affect the pharmacodynamics and pharmacokinetics of ticagrelor is a matter of broad clinical interest. The objective of this study was to investigate the effect of genetic polymorphisms on the pharmacokinetics and pharmacodynamics of ticagrelor in healthy Chinese subjects.This is a multi-center study in China, including three hospitals from Beijing, Nanchang, and Changsha. Healthy Chinese subjects aged 18-45 years with unknown genotypes were included. All subjects received a single oral dose of 90 mg of ticagrelor. Platelet aggregation and the area under the concentration-time curve for ticagrelor and its major active metabolite in plasma samples were assessed. Genome-wide association studies and candidate gene association analysis related to ticagrelor were performed.One hundred and seventy-five native Chinese subjects were enrolled and completed the study. According to the p value, the threshold of ticagrelor population was 6.57 × 10Genetic variation affects the pharmacokinetics and pharmacodynamics of ticagrelor in healthy individuals. The detection of NUP153, SVEP1 gene variation will be helpful for pharmacodynamic prediction and evaluation, and the regulation of these genes may be the target of new drug development. Further studies are required to confirm the results and explore whether these single-nucleotide polymorphisms are associated only with platelet activity or also with cardiovascular events and all-cause mortality.NCT03161002.

Sevoflurane (Sev) is a widely used inhalational anesthetic for general anesthesia in children. Previous studies have confirmed that multiple exposures to inhaled anesthetic can induce long-term neurotoxicity in newborn mice. However, the underlying mechanisms remain elusive. In this study, we investigated the role of homeodomain interacting protein kinase 2 (HIPK2), a stress activating kinase involved in neural survival and synaptic plasticity, and its underlying mechanism in sevoflurane-induced neurotoxicity. Empirical study showed that neuronal apoptosis was elevated after exposure to sevoflurane. Meanwhile, up-regulation of HIPK2 and AKT/mTOR signaling was observed in primary hippocampal neurons and hippocampus in mice upon anesthetic exposure. A64, antagonist of HIPK2, could significantly reduce increased apoptosis and activation of AKT/mTOR induced by sevoflurane. AKT antagonist MK2206 partially alleviated neuronal apoptosis without affecting the expression of HIPK2. Experimental results demonstrated a crucial role of HIPK2/AKT/mTOR signaling in neurotoxicity of sevoflurane. Thus, HIPK2/AKT/mTOR signaling can serve as a potential target for the protection of inhalation anesthesia-induced cytotoxicity in the future.

Amplification of the CCNE1 locus on chromosome 19q12 is prevalent in multiple tumour types, particularly in high-grade serous ovarian cancer, uterine tumours and gastro-oesophageal cancers, where high cyclin E levels are associated with genome instability, whole-genome doubling and resistance to cytotoxic and targeted therapies1–4. To uncover therapeutic targets for tumours with CCNE1 amplification, we undertook genome-scale CRISPR–Cas9-based synthetic lethality screens in cellular models of CCNE1 amplification. Here we report that increasing CCNE1 dosage engenders a vulnerability to the inhibition of the PKMYT1 kinase, a negative regulator of CDK1. To inhibit PKMYT1, we developed RP-6306, an orally bioavailable and selective inhibitor that shows single-agent activity and durable tumour regressions when combined with gemcitabine in models of CCNE1 amplification. RP-6306 treatment causes unscheduled activation of CDK1 selectively in CCNE1-overexpressing cells, promoting early mitosis in cells undergoing DNA synthesis. CCNE1 overexpression disrupts CDK1 homeostasis at least in part through an early activation of the MMB–FOXM1 mitotic transcriptional program. We conclude that PKMYT1 inhibition is a promising therapeutic strategy for CCNE1-amplified cancers.

INTRODUCTION: Splice modulators have been assessed clinically in treating haematologic malignancies exhibiting splice factor mutations and acute myeloid leukaemia. However, the mechanisms by which such modulators repress leukaemia remain to be elucidated. OBJECTIVES: The primary goal of this assessment was to assess the molecular mechanism by which the natural splice modulator GEX1A kills leukaemic cells in vitro and within in vivo mouse models. METHODS: Using human leukaemic cell lines, we assessed the overall sensitivity these cells have to GEX1A via EC(50) analysis. We subsequently analysed its effects using in vivo xenograft mouse models and examined whether cell sensitivities were correlated to genetic characteristics or protein expression levels. We also utilised RT-PCR and RNAseq analyses to determine splice change and RNA expression level differences between sensitive and resistant leukaemic cell lines. RESULTS: We found that, in vitro, GEX1A induced an MCL-1 isoform shift to pro-apoptotic MCL-1S in all leukaemic cell types, though sensitivity to GEX1A-induced apoptosis was negatively associated with BCL-xL expression. In BCL-2-expressing leukaemic cells, GEX1A induced BCL-2-dependent apoptosis by converting pro-survival BCL-2 into a cell killer. Thus, GEX1A + selective BCL-xL inhibition induced synergism in killing leukaemic cells, while GEX1A + BCL-2 inhibition showed antagonism in BCL-2-expressing leukaemic cells. In addition, GEX1A sensitised FLT3-ITD(+) leukaemic cells to apoptosis by inducing aberrant splicing and repressing the expression of FLT3-ITD. Consistently, in in vivo xenografts, GEX1A killed the bulk of leukaemic cells via apoptosis when combined with BCL-xL inhibition. Furthermore, GEX1A repressed leukaemia development by targeting leukaemia stem cells through inhibiting FASTK mitochondrial isoform expression across sensitive and non-sensitive leukaemia types. CONCLUSION: Our study suggests that GEX1A is a potent anti-leukaemic agent in combination with BCL-xL inhibitors, which targets leukaemic blasts and leukaemia stem cells through distinct mechanisms.

Cell migration depends on the dynamic organization of the actin cytoskeleton and assembly and disassembly of focal adhesions (FA). However the precise mechanisms coordinating these processes remain poorly understood. We previously identified the estrogen-related receptor α (ERRα) as a major regulator of cell migration. Here, we show that loss of ERRα leads to abnormal accumulation of actin filaments that is associated with an increase in the level of inactive form of the actin-depolymerizing factor cofilin. We further show that ERRα depletion decreases cell adhesion and promotes defective FA formation and turnover. Interestingly, specific inhibition of the RhoA-ROCK-LIMK-cofilin pathway rescues the actin polymerization defects resulting from ERRα silencing, but not cell adhesion. Instead we found that MAP4K4 is a direct target of ERRα and down-regulation of its activity rescues cell adhesion and FA formation in the ERRα-depleted cells. Altogether, our results highlight a crucial role of ERRα in coordinating the dynamic of actin network and focal adhesion through the independent regulation of the RhoA and MAP4K4 pathways.

Developmental and Epileptic Encephalopathy (DEE) is a group of disorders affecting children at early stages of infancy, which is characterized by frequent seizures, epileptiform activity on EEG, and developmental delayor regression. Developmental and epileptic encephalopathy-30 (DEE30) is a severe neurologic disorder characterized by onset of refractory seizures soon after birth or in the first months of life. Which was recently found to be caused by heterozygous mutations in the salt-inducible kinase SIK1. In this study, we investigated a patient with early onset epilepsy. DNA sequencing of the whole coding region revealed a de novel heterozygous nucleotide substitution (c.880G A) causing a missense mutation (p.A294T). This mutation was classified as variant of unknown significance (VUS) by American College of Medical Genetics and Genomics (ACMG). To further investigate the pathogenicity and pathogenesis of this mutation, we established a human neuroblastoma cell line (SH-SY5Y) stably-expressing wild type SIK1 and A294T mutant, and compared the transcriptome and metabolomics profiles. We presented a pediatric patient suffering from infantile onset epilepsy. Early EEG showed a boundary dysfunction of activity and MRI scan of the brain was normal. The patient responded well to single anti-epileptic drug treatment. Whole-exome sequencing found a missense mutation of SIK1 gene (c.880G A chr21: 43,420,326 p. A294T). Dysregulated transcriptome and metabolome in cell models expressing WT and MUT SIK1 confirmed the pathogenicity of the mutation. Specifically, we found MEF2C target genes, certain epilepsy causing genes and metabolites are dysregulated by SIK1 mutation. We found MEF2C target genes, certain epilepsy causing genes and metabolites are dysregulated by SIK1 mutation. Our finding further expanded the disease spectrum and provided novel mechanistic insights of DEE30.

Estrogen receptor α (ERα) is a target for the treatment of ER-positive breast cancer patients. Paradoxically, it is also the initial site for estrogen (E(2)) to induce apoptosis in endocrine-resistant breast cancer. How ERα exhibits distinct functions, in different contexts, is the focus of numerous investigation. Compelling evidence demonstrated that unfolded protein response (UPR) is closely correlated with ER-positive breast cancer. Treatment with antiestrogens initially induces mild UPR through ERα with activation of three sensors of UPR—PRK-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1α (IRE1α), and activating transcription factor 6 (ATF6)—in the endoplasmic reticulum. Subsequently, these sensors interact with stress-associated transcription factors such as c-MYC, nuclear factor-κB (NF-κB), and hypoxia-inducible factor 1α (HIF1α), leading to acquired endocrine resistance. Paradoxically, E(2) further activates sustained secondary UPR via ERα to induce apoptosis in endocrine-resistant breast cancer. Specifically, PERK plays a key role in inducing apoptosis, whereas IRE1α and ATF6 are involved in endoplasmic reticulum stress-associated degradation after E(2) treatment. Furthermore, persistent activation of PERK deteriorates stress responses in mitochondria and triggers of NF-κB/tumor necrosis factor α (TNFα) axis, ultimately determining cell fate to apoptosis. The discovery of E(2)-induced apoptosis has clinical relevance for treatment of endocrine-resistant breast cancer. All of these findings demonstrate that ERα and associated UPR are double-edged swords in therapy for ER-positive breast cancer, depending on the duration and intensity of UPR stress. Herein, we address the mechanistic progress on how UPR leads to endocrine resistance and commits E(2) to inducing apoptosis in endocrine-resistant breast cancer.

Phosphorylation catalyzed by protein kinases is the most common and important regulatory pathway in the adaptive physiological responses to the changes in nutrition and environment of yeast. This study focused on the functions of Elm1, Sak1, and Tos3, which are three upstream protein kinases of Snf1 in Saccharomyces cerevisiae, in response to high-glucose and heat shock stresses. Results suggested that changing the gene dosage of ELM1/SAK1/TOS3 had different effects under high-glucose and heat shock stresses. ELM1 and SAK1 overexpressions could enhance the tolerance of S. cerevisiae to high-glucose and heat shock stresses, respectively. Nevertheless, the overexpression of TOS3 decreased the tolerance to high-glucose stress, and a native level of Tos3 was important for the normal adaptation to heat shock condition. The overexpression of ELM1 increased the accumulation of trehalose and ergosterol and altered the composition of fatty acids with altered gene expressions involved in the metabolism of three metabolites. Enhanced resistance to heat shock stress in SAK1 overexpression might be related to the enhanced accumulation of trehalose and ergosterol and upregulated transcription of genes related to the metabolism of trehalose and ergosterol. Furthermore, Elm1 might regulate the metabolism of trehalose, ergosterol, and fatty acids in a Snf1-independent form under high-glucose stress. A Snf1-independent pathway might be involved in the regulation of trehalose metabolism by Sak1 under heat shock condition. However, Sak1 and Snf1 may have an indirect relationship in the regulation of ergosterol synthesis. KEY POINTS: • Altering the gene dosage of ELM1/SAK1/TOS3 had different effects on stress responses • Elm1 regulated high-glucose response in a Snf1-independent manner • Sak1 and Snf1 had an indirect relationship in the regulation of heat shock response.

The Hippo signalling pathway has emerged as a major player in many aspects of liver biology, such as development, cell fate determination, homeostatic function and regeneration from injury. The regulation of Hippo signalling is complex, with activation of the pathway by diverse upstream inputs including signals from cellular adhesion, mechanotransduction and crosstalk with other signalling pathways. Pathological activation of the downstream transcriptional co-activators yes-associated protein 1 (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ, encoded by WWTR1), which are negatively regulated by Hippo signalling, has been implicated in multiple aspects of chronic liver disease, such as the development of liver fibrosis and tumorigenesis. Thus, development of pharmacological inhibitors of YAP-TAZ signalling has been an area of great interest. In this Review, we summarize the diverse roles of Hippo signalling in liver biology and highlight areas where outstanding questions remain to be investigated. Greater understanding of the mechanisms of Hippo signalling in liver function should help facilitate the development of novel therapies for the treatment of liver disease.

Chemotherapy is an important treatment strategy for advanced hepatocellular carcinoma (HCC). Sorafenib is a first-line systemic drug that has been commonly used clinically for patients with advanced HCC. However, the high resistance rate of sorafenib in HCC patients often hinders its long-term efficacy. Therefore, it is vital to reveal the molecular mechanisms of sorafenib resistance in patients with HCC.In current study, we screened out fourteen genes that over-expressed in HCC specimens through integrative bioinformatics analysis. Here, maternal embryonic leucine zipper kinase (MELK) was highlighted as one of the most probable molecules. The Database for Annotation Visualization and Integrated Discovery (DAVID) program was utilized for functional pathway enrichment analysis. Real-time PCR (RT-PCR) and western blot were used to examine the expression levels of MELK. CCK-8, transwell, colony formation assays and flow cytometry were used to detect cell proliferation, the cell cycle. The dual luciferase assays were performed to study the targeting relationship between MELK and miR-142-5p.MELK expressions were correlated significantly with cell proliferation by regulating cell cycle and DNA replication. High MELK expression in patients with HCC indicated a poor prognosis both the overall and diseases free survival rates. MELK knockdown suppresses cell proliferation, migration and invasion in vitro. miR-142-5p regulates MELK expression through binding to the complementary sequence in the 3'-UTR regions. MELK knockdown enhances sensitivity of sorafenib in HCC sorafenib-resistant (HCC/SR) cells.MELK may serve as a potential prognostic marker in HCC and MELK knockdown enhanced sensitivity of HepG2/SR cells to sorafenib treatment. Our findings suggest that MELK/miR-142-5p axis could be a potentially therapeutic target for reversing the sorafenib resistance in HCC treatment.

The Hippo signal transduction network regulates transcription through Yap/Taz-Tead1-4 in many tissues including skeletal muscle. Whilst transgenic mice have been generated for many Hippo genes, the resultant skeletal muscle phenotypes were not always characterized. Here, we aimed to phenotype the hindlimb muscles of Hippo gene-mutated Lats1−/−, Mst2−/−, Vgll3−/−, and Vgll4+/− mice. This analysis revealed that Lats1−/− mice have 11% more slow type I fibers than age and sex-matched wild-type controls. Moreover, the mRNA expression of slow Myh7 increased by 50%, and the concentration of type I myosin heavy chain is 80% higher in Lats1−/− mice than in age and sex-matched wild-type controls. Second, to find out whether exercise-related stimuli affect Lats1, we stimulated C2C12 myotubes with the hypertrophy agent clenbuterol or the energy stress agent AICAR. We found that both stimulated Lats1 expression by 1.2 and 1.3 fold respectively. Third, we re-analyzed published datasets and found that Lats1 mRNA in muscle is 63% higher in muscular dystrophy, increases by 17–77% after cardiotoxin-induced muscle injury, by 41–71% in muscles during overload-induced hypertrophy, and by 19–21% after endurance exercise when compared to respective controls. To conclude, Lats1 contributes to the regulation of muscle fiber type proportions, and its expression is regulated by physiological and pathological situations in skeletal muscle.

OBJECTIVE Endoplasmic reticulum stress (ERS) might play a pivotal role in the persistence of metabolic syndrome (MS). Lipopolysaccharide (LPS) derived from various gram-negative bacteria could result in the ERS. Therefore, we aimed to investigate the association between LPS and ERS in MS. METHOD We enrolled 86 patients with MS and 42 healthy people aged 35-65 years. Body weight, waist circumference, blood pressure were measured. LPS, LBP and inflammation factors, fasting plasma glucose (FPG), insulin, total cholesterol (TC), triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), free fatty acid (FFA) were analyzed in blood plasma of patient's cohort. Body mass index (BMI) and HOMA-IR were calculated. The mRNA and protein expression of ERS GRP78, IRE1α, ASK1 and IKKβ, JNK1 were measured in blood plasma of patient's cohort by RT-PCR and Elisa. MS was defined by the updated National Cholesterol Education Program Adult Treatment Panel III criterion for Asian Americans. RESULTS BMI, waist circumference, blood pressure, FPG, insulin, HOMA-IR, TC, triglyceride, HDL-C, LDL-C, FFA and LPS, LBP, TNF-α, CRP, IL-1, IL-6, MCP-1 were significantly higher in patients with MS than healthy people (P

HIV-1 infection-induced cGAS–STING–TBK1–IRF3 signaling activates innate immunity to produce type I interferon (IFN). The HIV-1 nonstructural protein viral infectivity factor (Vif) is essential in HIV-1 replication, as it degrades the host restriction factor APOBEC3G. However, whether and how it regulates the host immune response remains to be determined. In this study, we found that Vif inhibited the production of type I IFN to promote immune evasion. HIV-1 infection induced the activation of the host tyrosine kinase FRK, which subsequently phosphorylated the immunoreceptor tyrosine-based inhibitory motif (ITIM) of Vif and enhanced the interaction between Vif and the cellular tyrosine phosphatase SHP-1 to inhibit type I IFN. Mechanistically, the association of Vif with SHP-1 facilitated SHP-1 recruitment to STING and inhibited the K63-linked ubiquitination of STING at Lys337 by dephosphorylating STING at Tyr162. However, the FRK inhibitor D-65495 counteracted the phosphorylation of Vif to block the immune evasion of HIV-1 and antagonize infection. These findings reveal a previously unknown mechanism through which HIV-1 evades antiviral immunity via the ITIM-containing protein to inhibit the posttranslational modification of STING. These results provide a molecular basis for the development of new therapeutic strategies to treat HIV-1 infection.

A harmonized balance between positive and negative regulation of pattern recognition receptor (PRR)-initiated immune responses is required to achieve the most favorable outcome for the host. This balance is crucial because it must not only ensure activation of the first line of defense against viral infection but also prevent inappropriate immune activation, which results in autoimmune diseases. Recent studies have shown how signal transduction pathways initiated by PRRs are positively and negatively regulated by diverse modulators to maintain host immune homeostasis. However, viruses have developed strategies to subvert the host antiviral response and establish infection. Viruses have evolved numerous genes encoding immunomodulatory proteins that antagonize the host immune system. This review focuses on the current state of knowledge regarding key host factors that regulate innate immune signaling molecules upon viral infection and discusses evidence showing how specific viral proteins counteract antiviral responses via immunomodulatory strategies., Immunology: Viral infection and host defenses In the initial stages of viral infection, the body relies on innate or non-specific immune signaling pathways to spur antiviral response mechanisms into action, however viruses have evolved to counteract these defense mechanisms. Jong-Soo Lee and colleagues from Chungnam National University in Daejeon, South Korea, review the signaling pathways and regulatory factors involved in these two opposing processes. The researchers detail the different molecular players involved in recognizing DNA or RNA from viruses and highlight the immune-modulating mechanisms by which viruses evade detection. A more complete knowledge of these pathways and their interactions could help drug developers identify new ways of treating or preventing viral infections. It could also provide insights into how autoimmunity and other problems can arise when these antiviral surveillance mechanisms fail to work correctly.

Background The long-term use of dexamethasone (Dex), a well-known immunosuppressant, leads to an imbalance in bone metabolism and rapid decline of bone mineral density due to apoptosis of osteoblasts. The molecular mechanisms by which Dex induces osteoblast apoptosis remain unclear. Materials and methods MC3T3-E1 cells were treated with 0, 10−8, 10−6, and 10−4 M Dex for 24 h. ATF6, phosphorylated PERK, PERK, phosphorylated IRE1, and IRE1 expression, cell apoptosis, and caspase-12 and caspase-3 activity were measured. CHOP expression and calcium ion influx rate were measured in cells treated with 0 and 10−4 M Dex for 24 h. The effect of 2-APB treatment was assessed in cells treated with 0 or 10−4 M Dex. Results Levels of ATF6 and phosphorylated PERK and IRE1 increased in a dose-dependent manner in MC3T3-E1 cells treated with 10−8, 10−6, and 10−4 M Dex, compared to the control group (P −6 and 10−4 M Dex had significantly increased apoptotic rates and caspase-12 and caspase-3 activities (P −4 M Dex had significantly increased CHOP levels and calcium ion influx rates (P −4 M Dex and 2-APB abrogated the observed increases in cell apoptosis and caspase-12 and caspase-3 activities (P Conclusions High doses of Dex induce CHOP expression by promoting calcium ion influx-dependent induction of ATF6, phosphorylated PERK and phosphorylated IRE1, which induce endoplasmic reticulum stress-mediated apoptosis in osteoblasts. 2-APB protects the osteoblasts from the effects of Dex, preventing endoplasmic reticulum stress-mediated apoptosis.

BACKGROUND The serum and glucocorticoid-induced kinase-1 (SGK1) belonging to the AGC protein kinase family phosphorylates serine and threonine residues of target proteins. It regulates numerous ion channels and transporters and promotes survival under cellular stress. Unique to SGK1 is a tight control at transcriptional and post-transcriptional levels. SGK1 regulates multiple signal transduction pathways related to tumor development. Several studies have reported that SGK1 is upregulated in different types of human malignancies and induces resistance against inhibitors, drugs, and targeted therapies. RESULTS AND CONCLUSION This review highlights the cellular functions of SGK1, its crucial role in cancer development, and clinical insights for SGK1 targeted therapies. Furthermore, the role of SGK1-mediated autophagy as a potential therapeutic target for cancer has been discussed.

Accumulation of misfolded proteins in ER activates the unfolded protein response (UPR), a multifunctional signaling pathway that is important for cell survival. The UPR is regulated by three ER transmembrane sensors, one of which is inositol-requiring protein 1 (IRE1). IRE1 activates a transcription factor, X-box binding protein 1 (XBP1), by removing a 26-base intron from XBP1 mRNA that generates spliced XBP1 mRNA (XBP1s). To search for XBP1 transcriptional targets, we utilized an XBP1s-inducible human cell line to limit XBP1 expression in a controlled manner. We also verified the identified XBP1-dependent genes with specific silencing of this transcription factor during pharmacological ER stress induction with both an N-linked glycosylation inhibitor (tunicamycin) and a non-competitive inhibitor of the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) (thapsigargin). We then compared those results to the XBP1s-induced cell line without pharmacological ER stress induction. Using next‐generation sequencing followed by bioinformatic analysis of XBP1 binding motifs, we defined an XBP1 regulatory network and identified XBP1 as a repressor of PUMA (a proapoptotic gene) and IRE1 mRNA expression during the UPR. Our results indicate impairing IRE1 activity during ER stress conditions accelerates cell death in ER stressed cells, whereas elevating XBP1 expression during ER stress using an inducible cell line correlated with a clear prosurvival effect and reduced PUMA protein expression. Although further studies will be required to test the underlying molecular mechanisms involved the relationship between these genes with XBP1, these studies identify a novel repressive role of XBP1 during the UPR.

A limited delivery of oxygen and metabolic substrate to the heart caused by myocardial infarction (MI) impairs the cardiac function, and often results in heart failure. Here, we identified a circRNA (circ-SNRK) from SNRK (sucrose nonfermenting 1-related kinase, which can increase the cardiac mitochondrial efficiency) in cardiomyocytes (CMs). Circ-SNRK can sponge the miR-33 and in turn improved the ATP synthesis via SNRK, proving the existence of circ-SNRK - miR-33 - SNRK axis. Furthermore, we found that protein NOVA1 (NOVA alternative splicing regulator 1) could accelerate the circ-SNRK formation; a cleaved peptide (~55 kDa) from SNRK enters the nucleus and blocks the cyclization of circ-SNRK via binding to NOVA1. The aforementioned negative feedback of SNRK to circ-SNRK limited the SNRK at a proper level, and inhibited the protective role of circ-SNRK in ischemic heart. In addition, our in vivo experiment indicated that the overexpression of exogenic circ-SNRK could break this loop and improves the cardiac function post-MI in rats. Together, our results demonstrated that the negative loop of circ-SNRK with SNRK regulates the energy metabolism in CMs, thus might be a potential therapeutic target for heart failure.

Aberrations of the STK4 gene in humans result in an autosomal recessively inherited primary immunodeficiency. We identified three patients with STK4 deficiency who had presented to our hospital and reviewed their biopsy samples with the goal of detailing the characteristics of STK4 deficiency from a pathology perspective. Case 1 was a 20-year-old male who presented with cervical and supraclavicular lymphadenopathy which showed plasmacytic hyperplasia and a concurrent bronchial mass, with AA amyloidosis and EBV-associated "polymorphic lymphoproliferative disorder (LPD) resembling polymorphic post-transplant LPD." The second case was an 8-year-old girl with abdominal lymphadenopathy; biopsy revealed a complex lymphoproliferation which consisted of EBV-associated "polymorphic LPD resembling polymorphic post-transplant LPD," plasmacytic hyperplasia, granulomatous reaction, and a CD4- and PD-1-positive clonal T cell proliferation. The third was a 15-year-old girl with a laryngeal mass, representing a high-grade B cell lymphoma with prominent plasmacytic differentiation. Our cases emphasize the complex and challenging histopathology of lymphoid proliferations in patients with STK4 deficiency.

Eosinophilic inflammation is a feature of allergic asthma. Despite mounting evidence showing that chromatin filaments released from neutrophils mediate various diseases, the understanding of extracellular DNA from eosinophils is limited. Here we show that eosinophil extracellular traps (EETs) in bronchoalveolar lavage fluid are associated with the severity of asthma in patients. Functionally, we find that EETs augment goblet-cell hyperplasia, mucus production, infiltration of inflammatory cells and expressions of type 2 cytokines in experimental non-infection-related asthma using both pharmaceutical and genetic approaches. Multiple clinically relevant allergens trigger EET formation at least partially via thymic stromal lymphopoietin in vivo. Mechanically, EETs activate pulmonary neuroendocrine cells via the CCDC25-ILK-PKCα-CRTC1 pathway, which is potentiated by eosinophil peroxidase. Subsequently, the pulmonary neuroendocrine cells amplify allergic immune responses via neuropeptides and neurotransmitters. Therapeutically, inhibition of CCDC25 alleviates allergic inflammation. Together, our findings demonstrate a previously unknown role of EETs in integrating immunological and neurological cues to drive asthma progression.

Diffuse-type gastric cancers (DGC) typically have a poor prognosis related to their invasion and metastasis, in which the epithelial–mesenchymal transition (EMT) is the initiation step. ULK2 plays a role in the autophagy initiation, which might provide a survival advantage in cancer cells. Although knock-down of ULK2 reportedly induces autophagy and EMT in a lung cancer cell line, the mechanism of EMT via the down-regulation of ULK2, as well as its clinical significance, remains yet unclear. The present study, therefore, aims at clarifying this mechanism and its clinical significance in gastric cancers. We examined ULK2 mRNA expression in gastric cancer tissues and normal gastric tissues of healthy people. The effects of knock-downed ULK2 were examined in two gastric cancer cells, which were investigated in terms of their gene expression changes by the mRNA microarray. ULK2 was strongly expressed in intestinal-type cancers but was scarcely expressed in DGC by immunohistochemical staining. Furthermore, we found that ULK2 was methylated in DGC and was unmethylated in corresponding adjacent normal tissues. Then, we validated whether knock-down of ULK2 could induce autophagy, cell migration, and EMT in NUGC3 and MKN45 cells. Using mRNA microarray analysis, we confirmed that knock-down of ULK2 changed expressions of oncogenic genes associated with cell migration and EMT. Autophagy inhibitor suppressed cell migration and EMT induced by knock-down of ULK2 in NUGC3 and MKN45. Methylation silencing of ULK2 could induce cell migration and EMT by means of autophagy induction, causing transformation to poorly differentiated cancers.

Dual-specificity tyrosine phosphorylation-regulated kinases (DYRKs) are activated via the auto-phosphorylation of conserved tyrosine residues in their activation loop during protein translation, and they then phosphorylate serine/threonine residues on substrates. The DYRK family is widely conserved in eukaryotes and is composed of six subgroups. In plant lineages, DYRK homologs are classified into four subgroups, DYRK2s, yet another kinase1s, pre-mRNA processing factor 4 kinases, and DYRKPs. Only the DYRKP subgroup is plant-specific and has been identified in a wide array of plant lineages, including land plants and green algae. It has been suggested that in Arabidopsis thaliana DYRKPs are involved in the regulation of centripetal nuclear positioning induced by dark light conditions. However, the molecular functions, such as kinase activity and the developmental and physiological roles of DYRKPs are poorly understood. Here, we focused on a sole DYRKP ortholog in the model bryophyte, Marchantia polymorpha, MpDYRKP. MpDYRKP has a highly conserved kinase domain located in the C-terminal region and shares common sequence motifs in the N-terminal region with other DYRKP members. To identify the roles of MpDYRKP in M. polymorpha, we generated loss-of-function Mpdyrkp mutants via genome editing. Mpdyrkp mutants exhibited abnormal, shrunken morphologies with less flattening in their vegetative plant bodies, thalli, and male reproductive organs, antheridial receptacles. The surfaces of the thalli in the Mpdyrkp mutants appeared uneven and disordered. Moreover, their epidermal cells were drastically altered to a narrower shape when compared to the wild type. These results suggest that MpDYRKP acts as a morphological regulator, which contributes to orderly tissue morphogenesis via the regulation of cell shape.

There has been accumulating evidence for the clinical benefit of chemoradiation therapy (CRT), whereas mechanisms in CRT-recurrent clones derived from the primary tumor are still elusive. Herein, we identified an aberrant BUB1B/BUBR1 expression in CRT-recurrent clones in bladder cancer (BC) by comprehensive proteomic analysis. CRT-recurrent BC cells exhibited a cell-cycle-independent upregulation of BUB1B/BUBR1 expression rendering an enhanced DNA repair activity in response to DNA double-strand breaks (DSBs). With DNA repair analyses employing the CRISPR/cas9 system, we revealed that cells with aberrant BUB1B/BUBR1 expression dominantly exploit mutagenic nonhomologous end joining (NHEJ). We further found that phosphorylated ATM interacts with BUB1B/BUBR1 after ionizing radiation (IR) treatment, and the resistance to DSBs by increased BUB1B/BUBR1 depends on the functional ATM. In vivo, tumor growth of CRT-resistant T24R cells was abrogated by ATM inhibition using AZD0156. A dataset analysis identified FOXM1 as a putative BUB1B/BUBR1-targeting transcription factor causing its increased expression. These data collectively suggest a redundant role of BUB1B/BUBR1 underlying mutagenic NHEJ in an ATM-dependent manner, aside from the canonical activity of BUB1B/BUBR1 on the G2/M checkpoint, and offer novel clues to overcome CRT resistance.