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Background and Purpose: Cannabis stimulates several G‐protein‐coupled‐receptors and causes bradycardia and hypotension upon sustained consumption. Moreover, in vitro studies suggest an interference of cannabinoid‐signalling with cardiomyocyte contractility and hypertrophy. We aimed at revealing a functional contribution of the cannabinoid‐sensitive receptor GPR55 to cardiomyocyte homeostasis and neurohumorally induced hypertrophy in vivo. Experimental Approach: Gpr55−/− and wild‐type (WT) mice were characterized after 28‐day angiotensin II (AngII; 1·μg·kg−1 min−1) or vehicle infusion. In isolated adult Gpr55−/− and WT cardiomyocytes, mitochondrial function was assessed under naïve conditions, while cytosolic Ca2+ handling was additionally determined following application of the selective GPR55 antagonist CID16020046. Key Results: Gpr55 deficiency did not affect angiotensin II (AngII) mediated hypertrophic growth, yet, especially in females, it alleviated maladaptive pro‐hypertrophic and ‐inflammatory gene expression and improved inotropy and adrenergic responsiveness compared to WT. In‐depth analyses implied increased cytosolic Ca2+ concentrations and transient amplitudes, and accelerated sarcomere contraction kinetics in Gpr55−/− myocytes, which could be mimicked by GPR55 blockade with CID16020046 in female WT cells. Moreover, Gpr55 deficiency up‐regulated factors involved in glucose and fatty acid transport independent of the AngII challenge, accelerated basal mitochondrial respiration and reduced basal protein kinase (PK) A, G and C activity and phospholemman (PLM) phosphorylation. Conclusions and Implications: Our study suggests GPR55 as crucial regulator of cardiomyocyte hypertrophy and homeostasis presumably by regulating PKC/PKA‐PLM and PKG signalling, and identifies the receptor as potential target to counteract maladaptation, adrenergic desensitization and metabolic shifts as unfavourable features of the hypertrophied heart in females. [ABSTRACT FROM AUTHOR]

ABSTRACT Swedish Warmblood horses (SWB) are bred for show jumping and/or dressage with young horse test scores as indicator traits. This study aimed to investigate possible candidate genes and regions of importance for evaluated and linearly scored young horse test traits. A single‐step genome‐wide association study (ssGWAS) was done using the BLUPF90 suite of programs for factors scores from factor analysis of traits assessed at young horse tests together with height at withers. The ssGWAS included 20,814 SWB with factors scores for four factors for evaluated traits. A total of 6436 of these horses also had factor scores for 13 factors for linearly scored traits. Genotypes from a 670K SNP array were available for 380 of the horses in this study. All genotyped horses had factor scores for evaluated traits, and 379 also had factors scores for linearly scored traits. Significant SNPs associated with three factors related to size were located on ECA3 within or nearby a well‐known region, including the genes ligand dependent nuclear receptor corepressor like (LCORL), non‐SMC condensin I complex subunit G (NCAPG), DDB1 and CUL4 Associated Factor 16 (DCAF16), and the Family with Sequence Similarity 184 Member B (FAM184B). Significant SNPs were also detected for two factors for evaluated traits representing conformation and jumping, and four factors for linearly scored traits related to body length, neck conformation, walk and trot (hindleg position and activity), respectively. Among nearby genes, calcium/calmodulin‐dependent protein kinase type 1D (CAMK1D) for the factor for linearly scored traits related to neck conformation and GLI Family Zinc Finger 2 (GLI2) for the factor for evaluated jumping traits, were most promising. For these, top associated SNPs were detected within the genes, and the known gene functions seems to be related to the phenotypes. In conclusion, ssGWAS is beneficial to detect plausible candidate genes/regions for desired traits in warmblood horses. [ABSTRACT FROM AUTHOR]

ABSTRACT Panniculitides are a group of inflammatory disorders of the subcutaneous fat that have been reported as a rare complication of both a serine threonine kinase BRAF inhibitor monotherapy and BRAF inhibition in combination with a mitogen activated protein kinase (MEK) inhibitor combination therapy used to treat metastatic melanoma. The cutaneous manifestations of BRAF and BRAF/MEK therapies have been well documented, but neutrophilic panniculitis remains a less common complication with fewer case reports. Physician awareness of this complication when following patients on similar targeted therapies can decrease delays in appropriate management. We report a case of one patient who developed neutrophilic panniculitis during treatment with the BRAF/MEK combination of dabrafenib and trametinib. We followed the patient from initial presentation in the emergency department to diagnosis to include pathology findings of the disease. In this case of neutrophilic panniculitis, the patient presented with a history of stage IIIa (pT2a N1a M0) cutaneous melanoma of the right flank and developed classic painful nodules on the lower legs and arms with associated fever within the first 2 weeks after initiating adjuvant melanoma targeted therapy. The biopsies showed a mixed, neutrophilic panniculitis, without overlying epidermal changes. Given the patient's clinical history, the biopsy was consistent with a BRAF inhibitor induced neutrophilic panniculitis. The panniculitis resolved with symptomatic care and the patient was maintained on the antitumor therapies. [ABSTRACT FROM AUTHOR]

The αLβ2 integrin LFA‐1 plays a key role in T‐cell adhesion to the endothelial vasculature and migration into both secondary lymphoid organs and peripheral tissues via interactions with its target protein ICAM‐1, but the pathways that regulate LFA‐1‐mediated T‐cell polarity and migration are not fully understood. In this study we screened two RNAi libraries targeting G protein‐coupled receptors (GPCR)/GPCR‐associated proteins and kinases in a HuT 78 T cell line model of LFA‐1‐stimulated T‐cell migration. Based on staining of the actin cytoskeleton, multiple parameters to measure cell morphology were used to assess the contribution of 1109 genes to LFA‐1‐mediated T‐cell polarity and migration. These RNAi screens identified a number of both novel and previously identified genes that either increased or decreased the polarity and migratory capacity of these cells. Following multiparametric analysis, hierarchical clustering and pathway analysis, three of these genes were characterized in further detail using primary human T cells, revealing novel roles for the heterotrimeric G protein subunit Gβ1 and Casein Kinase 2 in LFA‐1‐mediated T‐cell polarity and migration in vitro. Our studies also highlighted a new role for ICAP‐1, an adaptor protein previously described to be associated with β1 integrins, in β2 integrin LFA‐1‐directed migration in T cells. Knockdown of ICAP‐1 expression in primary T cells revealed a role in cell polarity, cell velocity and transmigration towards SDF‐1 for this adaptor protein. This study therefore uncovers new roles for GPCR/GPCR‐associated proteins and kinases in T‐cell migration and provides potential novel targets for modulation of the T‐cell immune response. [ABSTRACT FROM AUTHOR]

Protein kinases are key regulators of numerous biological processes and aberrant kinase activity can cause various diseases, particularly cancer. Herein, we report the identification of new series of highly selective kinase inhibitors based on the thieno[3,2‐b]pyridine scaffold. The weak interaction of the thieno[3,2‐b]pyridine core with the kinase hinge region allows for profoundly different binding modes all of which maintain high kinome‐wide selectivity, as illustrated by the isomers MU1464 and MU1668. Thus, this core structure provides a template of ATP‐competitive but not ATP‐mimetic inhibitors that are anchored at the kinase back pocket. Mapping the chemical space around the central thieno[3,2‐b]pyridine pharmacophore afforded highly selective inhibitors of the kinase Haspin, exemplified by the compound MU1920 that fulfils criteria for a quality chemical probe and is suitable for use in in vivo applications. However, despite the role of Haspin in mitosis, the inhibition of Haspin alone was not sufficient to elicit cytotoxic effect in cancer cells. The thieno[3,2‐b]pyridine scaffold can be used in a broader context, as a basis of inhibitors targeting other underexplored protein kinases, such as CDKLs. [ABSTRACT FROM AUTHOR]

Background Objectives Materials and methods Results Discussion Conclusion Endocannabinoids like anandamide (AEA), among other lipids, are recognized signaling molecules that participate in reproductive events.Our aims were to characterize orphan G protein‐coupled receptor (GPR55) presence; investigate GPR55 activation by AEA and determine GPR55 role in the bovine sperm function.GPR55 presence was assessed by immunocytochemistry. Protein kinase A (pPKA) and PKC (pPKC) substrates, pERK1/2, G/F‐actin were determined by Western blotting, activation of RAC‐1 by pull‐down assay, F‐actin and acrosomal exocytosis by fluorescence microscopy, sperm motility by optic microscopy and computer‐aided sperm analysis and fertilizing ability by in vitro fertilization (IVF).We detected GPR55 in spermatozoa at T0, after incubation in non‐capacitating and capacitating (presence of AEA) conditions and upon release from oviductal epithelia. AEA induced an increase in pPKA and pPKC, while CID16020046 (CID), selective GPR55 antagonist, prevented this effect. Incubation with H89, PKA inhibitor, significantly decreased pPKC, while Gö6983, a PKC inhibitor, partially reduced pPKA. pPKA remained elevated at 15‐ and 45‐min incubation, while pPKC decreased at 15 and increased at 45 min. CID prevented pPKC increase at 5 and 45 min and decreased pPKA at 45 min. RAC‐1 and F‐actin increase induced by AEA was prevented by CID. Variations in two progressive motility kinematic parameters were observed with AEA and/or CID. Sperm pretreatment with AEA increased the rate of cleaved embryos and CID prevented this effect.We demonstrated that GPR55 activation by AEA induces time‐dependent signaling pathways involving pPKA and pPKC during bovine sperm capacitation. AEA regulates actin polymerization through GPR55 activation, suggesting the receptor participates in cytoskeleton remodeling, and yielded higher IVF rates. Also, sperm pre‐incubation with molecules like AEA involved in capacitation could improve the embryo development.We have demonstrated GPR55 presence in bovine spermatozoa. The regulation of PKA and PKC and of molecules associated with cytoskeletal dynamics, such as RAC‐1 and actin, by GPR55 is closely related to sperm motility and acrosomal exocytosis. [ABSTRACT FROM AUTHOR]

Summary: Nitrate (NO3−) serves as the primary inorganic nitrogen source assimilated by most terrestrial plants. The acquisition of nitrate from the soil is facilitated by NITRATE TRANSPORTERS (NRTs), with NRT2.1 being the key high‐affinity nitrate transporter. The activity of NRT2.1, which has multiple potential phosphorylation sites, is intricately regulated under various physiological conditions. Here, we discovered that CALCIUM‐DEPENDENT PROTEIN KINASE 28 (CPK28) positively regulates nitrate uptake under nitrogen deprivation conditions.We found CPK28 as the kinase targeted by immunoprecipitation followed by mass spectrometry and examined the in‐planta phosphorylation status of NRT2.1 in cpk28 mutant plants by employing quantitative MS‐based phosphoproteomics. Through a combination of in vitro phosphorylation experiment and immunoblotting using phospho‐specific antibody, we successfully demonstrated that CPK28 specifically phosphorylates NRT2.1 at Ser21.Functional analysis conducted in Xenopus oocytes revealed that co‐expression of CPK28 significantly enhanced high‐affinity nitrate uptake of NRT2.1. Further investigation using transgenic plants showed that the phosphomimic variant NRT2.1S21E, but not the nonphosphorylatable variant NRT2.1S21A, fully restored high‐affinity 15NO3− uptake ability in both nrt2.1 and cpk28 mutant backgrounds.This study clarifies that the kinase activity of CPK28 is promoted during nitrogen deprivation conditions. These significant findings provide valuable insights into the intricate regulatory mechanisms that govern nitrate‐demand adaptation. [ABSTRACT FROM AUTHOR]

Crizotinib, as the first‐generation of anaplastic lymphoma kinase (ALK) inhibitor, effectively improves the survival time of ALK‐positive non‐small cell lung cancer (NSCLC) patients. However, its efficacy is severely limited by drug resistance caused by secondary mutations. G1202R and L1196M are classical mutation sites located in ALK kinase domain. They may hinder the binding of ALK inhibitors to the target kinase domain, resulting in drug resistance in patients. However, the exact mechanism of drug resistance mediated by these mutations remains unclear. In this study, we aimed to evaluate how G1202R and L1196M mutations mediate crizotinib resistance. To explore the resistance mechanism, we constructed EML4‐ALK G1202R and L1196M mutant cell lines with A549 cells. The results showed that the mutant cells exhibited significant epithelial–mesenchymal transition (EMT) and metastasis compared to control (A549‐vector) or wild type (A549‐EML4‐ALK) cells. Subsequently, it was found that the occurrence of EMT was correlated to the high expression of murine double minute 2 (MDM2) protein and the activation of mitogen‐activated protein kinase (MEK)/extracellular signal‐regulated kinase (ERK) pathway in mutant cells. Down‐regulation of MDM2 inhibited the activation of MEK/ERK pathway, thus reversed the EMT process and markedly increased the inhibitory effect of crizotinib on the growth of mutant cells. Collectively, resistance of ALK‐positive NSCLC cells to crizotinib is induced by G1202R and L1196M mutations through activation of the MDM2/MEK/ERK signalling axis, promoting EMT process and metastasis. These findings suggest that the combination of MDM2 inhibitors and crizotinib could be a potential therapeutic strategy. [ABSTRACT FROM AUTHOR]

ABSTRACT Low temperature is a limiting environmental factor for tea plant growth and development. CBL‐interacting protein kinases (CIPKs) are important components of the calcium pathway and involved in plant development and stress responses. Herein, we report the function and regulatory mechanisms of a low‐temperature‐inducible gene, CsCIPK20, in tea plants. The overexpression of CsCIPK20 in Arabidopsis and its transient knockdown in tea plants confirmed its positive role in cold resistance. Notably, the ascorbic acid (AsA) levels increased in the overexpression lines and decreased in the CsCIPK20 knockdown tea plants under freezing stress. Transcriptomic analysis revealed that genes involved in flavonoid metabolism, glutathione metabolism, and AsA biosynthesis were significantly regulated by CsCIPK20. Furthermore, we found that CsCSN5, a key component of the COP9 signalosome, interacted with CsCIPK20 to mediate CsCIPK20 degradation. CsCSN5 interacted with CsVTC1, a key enzyme in AsA biosynthesis, and mediated CsVTC1 degradation. Knockdown of CsVTC1 in tea plants enhanced sensitivity to low temperature. Moreover, we demonstrated that CsCIPK20 competed with CsVTC1 to bind to CsCSN5, which protected CsVTC1 from degradation mediated by CsCSN5 and contributed to AsA accumulation. Overall, our findings uncovered a mechanistic framework through which the CsCIPK20‐CsCSN5‐CsVTC1 module mediated AsA accumulation and low‐temperature resistance in tea plants. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Materials and Methods Results Conclusion Porphyromonas gingivalis, a consensus periodontal pathogen, is thought to be involved in Alzheimer's disease (AD) progression, and P. gingivalis‐derived outer membrane vesicles (PgOMVs) are a key toxic factor in inducing AD pathology. This study aimed to clarify the regulatory mechanism underlying the PgOMV‐induced AD‐like phenotype.We intraperitoneally injected PgOMVs into the periphery of wild‐type and CatB knockout mice for 4 or 8 weeks to assess the effect of CatB on PgOMV‐induced AD pathology. Mice were evaluated for cognitive change, tau phosphorylation, microglial activation, neuroinflammation and synapse loss. Microglial and primary neuron culture were prepared to verify the in vivo results.CatB deficiency significantly alleviated PgOMV‐induced cognitive dysfunction, microglia‐mediated neuroinflammation, tau hyperphosphorylation and synapse loss. Subsequent transcriptomic analysis, immunofluorescence and immunoblotting suggested that CatB modulates microglia‐mediated neuroinflammation through stress‐activated protein kinases (SAPK)/Jun amino‐terminal kinases (JNK) signals after administration of PgOMVs, which in turn regulates neuronal tau phosphorylation and synapse loss in a SAPK/JNK‐dependent manner.Our study unveils a previously unknown role of CatB in regulating PgOMV‐induced AD pathology. [ABSTRACT FROM AUTHOR]

Aims Methods Results Conclusions Acute hypoglycaemia promotes pro‐inflammatory cytokine production, increasing the risk for cardiovascular events in diabetes. AMP‐activated protein kinase (AMPK) is regulated by and influences the production of pro‐inflammatory cytokines. We sought to examine the mechanistic role of AMPK in low glucose‐induced changes in the pro‐inflammatory cytokine macrophage migration inhibitory factor (MIF), which is elevated in people with diabetes.Macrophage cell line Raw264.7 cells, primary macrophage bone marrow‐derived macrophages obtained from wild‐type mice or AMPK γ1 gain‐of‐function mice, were used, as were AMPKα1/α2 knockout mouse embryonic fibroblasts (MEFs). Allosteric AMPK activators PF‐06409577 and BI‐9774 were used in conjunction with inhibitor SBI‐0206965. We examined changes in protein phosphorylation/expression using western blotting and protein localisation using immunofluorescence. Metabolic function was assessed using extracellular flux analyses and luciferase‐based ATP assay. Cytokine release was quantified by enzyme‐linked immunosorbent assay (ELISA). Oxidative stress was detected using a fluorescence‐based reactive oxygen species (ROS) assay, and cell viability was examined using flow cytometry.Macrophages exposed to low glucose showed a transient and modest activation of AMPK and a metabolic shift towards increased oxidative phosphorylation. Moreover, low glucose increased oxidative stress and augmented the release of macrophage MIF. However, pharmacological activation of AMPK by PF‐06409577 and BI‐9774 attenuated low glucose‐induced MIF release, with a similar trend noted with genetic activation using AMPKγ1 gain‐of‐function (D316A) mice, which produced a mild effect on low glucose‐induced MIF release. Inhibition of NFĸB signalling diminished MIF release and AMPK activation modestly but significantly reduced low glucose‐induced nuclear translocation of NFĸB.Taken together, these data indicate that pharmacological AMPK activation suppresses the release of MIF from macrophages caused by energy stress, suggesting that AMPK activation could be a useful strategy for mitigating hypoglycaemia‐induced inflammation. [ABSTRACT FROM AUTHOR]

The study investigated the potential alleviating effect of sodium butyrate (SB) on intestinal injuries caused by glycinin in the diet of common carp. Fish were divided into six groups: a control group (without glycinin and SB), a Gly group (with glycinin), and four groups supplemented with different doses of SB (0.75, 1.50, 2.25, and 3.00 g/kg) based on the Gly group. All diets were isonitrogenous and isoenergetic, and the fish were fed these diets for 8 weeks. The results indicated that glycinin activated the mitogen‐activated protein kinase (MAPK) signaling pathway, leading to upregulating ERK, JNK, and p38 gene expression in the intestine. However, SB2 and SB3 groups were able to inhibit this pathway. Furthermore, glycinin upregulated the expression of proapoptotic genes (Bax, Caspase‐3, Caspase‐8, and Caspase‐9) while downregulating the antiapoptotic gene Bcl2. The SB2 and SB3 groups were found to alleviate glycinin‐induced apoptosis. Additionally, dietary glycinin significantly decreased the expression of tight junction genes (ZO‐1, Claudin3, Claudin7, and Occludin1) in the intestine, whereas the SB2 and SB3 groups improved intestinal barrier function. Glycinin also elevated serum levels of d‐lactate, diamine oxidase, serotonin, and endothelin, resulting in intestinal damage and increased permeability. In contrast, the SB2 and SB3 groups reduced these serum levels, thereby regulating intestinal permeability. Moreover, glycinin disrupted the intestinal morphology, which was mitigated by the SB2 and SB3 groups by increasing the height and width of intestinal villi folds. Lastly, dietary glycinin altered the intestinal microecological balance by increasing Proteobacteria abundance and decreasing Clostridium and Bacteroidetes abundance. The SB2 and SB3 groups modulated the composition of dominant taxa by increasing Firmicutes and Acidobacteria abundance. Overall, SB was found to mediate the MAPK signaling pathway, apoptosis, upregulation of tight junction genes, maintenance of the intestinal physical barrier, and regulation of intestinal flora, thereby alleviating glycinin‐induced intestinal damage. [ABSTRACT FROM AUTHOR]

Tendinopathy poses a formidable challenge due to the inherent limitations of tendon regenerative capabilities post‐injury. At present, effective curative approaches for tendinopathy are still lacking. Collagen triple helix repeat‐containing 1 (CTHRC1) is an extracellular matrix protein with significant roles in both physiological and pathological processes. The present study aims to investigate the function and underlying mechanism of CTHRC1 in tendinopathy. In this study, CTHRC1 is identified as a potential effector in promoting tendon regeneration through multi‐proteomic analysis of Achilles tendon tissues in mice. In vitro, CTHRC1 enhances the proliferation, migration, and tenogenic differentiation of tendon stem/progenitor cell (TSPC). In vivo, CTHRC1 deletion impairs tendon healing, while its overexpression reverses the detrimental effects caused by CTHRC1 deficiency. Mechanistically, proteomics on TSPC stimulated with recombinant CTHRC1 reveal that CTHRC1 activates the mitogen‐activated protein kinase (MAPK) signaling pathway via binding to epidermal growth factor receptor (EGFR), which in turn promotes the proliferative, migrative, and tenogenic capacities of TSPC to attenuate Achilles tendinopathy. Conversely, inhibiting EGFR reverses the tendon‐healing effect of CRHRC1. The study demonstrates that CTHRC1 can promote the proliferative, migrative, and tenogenic capacities of TSPC, ultimately facilitating tendon healing through activating the EGFR/MAPK signaling pathway. CTHRC1 holds promise as a potential intervention for tendinopathy. [ABSTRACT FROM AUTHOR]

Summary: The calcium‐dependent protein kinase CPK28 regulates several stress pathways in multiple plant species. Here, we aimed to discover CPK28‐associated proteins in Arabidopsis thaliana.We used affinity‐based proteomics and identified several potential CPK28 binding partners, including the C7 Raf‐like kinases MRK1, RAF26, and RAF39. We used biochemistry, genetics, and physiological assays to gain insight into their function.We define redundant roles for these kinases in stomatal opening, immune‐triggered reactive oxygen species (ROS) production, and resistance to a bacterial pathogen. We report that CPK28 associates with and trans‐phosphorylates RAF26 and RAF39, and that MRK1, RAF26, and RAF39 are active kinases that localize to endomembranes. Although Raf‐like kinases share some features with mitogen‐activated protein kinase kinase kinases (MKKKs), we found that MRK1, RAF26, and RAF39 are unable to trans‐phosphorylate any of the 10 Arabidopsis mitogen‐activated protein kinase kinases (MKKs).Overall, our study suggests that C7 Raf‐like kinases associate with and are phosphorylated by CPK28, function redundantly in stomatal opening and immunity, and possess substrate specificities distinct from canonical MKKKs. [ABSTRACT FROM AUTHOR]

Background and Purpose: Diabetic patients have an increased risk of psychiatric disorders. Because hyperglycaemia increases L‐lactate in the brain and L‐lactate inhibits AMP‐activated protein kinase (AMPK), this study investigated the role of L‐lactate and AMPK in strengthened fear memory, a model for human psychiatric disorders, in diabetic mice. Experimental Approach: The diabetic model was mice injected with streptozotocin. Fear memory was measured using the conditioned fear test with low (0.45 mA) or high (0.50 mA) foot shock to cause low and high freezing, respectively. Protein levels of AMPK and phosphorylated AMPK (pAMPK) were measured by western blotting and immunohistochemistry. Key Results: At 0.45 mA, the AMPK inhibitor dorsomorphin increased freezing, which was inhibited by the AMPK activator acadesine. In contrast, at 0.50 mA, acadesine decreased freezing, which was inhibited by dorsomorphin. In diabetic mice, pAMPK was decreased in the amygdala and hippocampus. Diabetic mice showed increased freezing at 0.45 mA, which was inhibited by acadesine. In the amygdala and hippocampus, L‐lactate was increased in diabetic mice and injection of L‐lactate into non‐diabetic mice increased freezing at 0.45 mA. In addition, L‐lactate decreased pAMPK in the hippocampus, but not the amygdala, and increase in freezing induced by L‐lactate was inhibited by acadesine. Dorsomorphin‐induced increase in freezing was inhibited by the AMPA receptor antagonist NBQX. Conclusions and Interpretation: In diabetic mice, L‐lactate is increased in the amygdala and hippocampus, possibly through hyperglycaemia, which strengthens fear memory through inhibition of AMPK and activation of glutamatergic function. [ABSTRACT FROM AUTHOR]

Non‐small cell lung cancer comprises up to 85% of lung cancer cases and has a poor prognosis. At present, there are still no effective treatments for this illness. Evidence suggests that the prostaglandin [cyclooxygenase‐2 (COX‐2)] and leukotriene [lipoxygenase‐5 (5‐LOX)] pathways are involved in lung cancer carcinogenesis. Therefore, novel agents that target COX‐2 and 5‐LOX may have therapeutic potential. In the present study, we examined the role of asiatic acid (AA), a triterpenoid saponin, in targeting the protein kinases responsible for lung cancer proliferation and mobility. The experimental data revealed that AA inhibited the growth of lung cancer cells (> 50%) and it significantly impeded the proliferation of lung cancer cells by inhibiting COX‐2, which results in downregulation of the phosphotidyl inositol‐3 kinase/protein kinase B/mammalian target of rapamycin signaling pathway, leading to an induction of cytotoxic autophagy‐mediated apoptosis. Mechanistically, the expression of mitogen‐activated protein kinase/extracellular signal‐regulated kinase, hypoxia‐inducible factor‐1 and vascular endothelial growth factor is downregulated by AA, thereby reducing cell mobility and invasion. It also shows negative osmotic fragility on healthy human erythrocytes. It is concluded that AA may be a viable therapeutic drug for non‐small cell lung cancer treatment, which opens new opportunities for synthesizing analogues. [ABSTRACT FROM AUTHOR]

Summary: Mechanisms underlying potentiation of the anti‐myeloma (MM) activity of ataxia telangiectasia Rad3 (ATR) antagonists by MAPK (Mitogen‐activated protein kinases)‐related extracellular kinase 1/2 (MEK1/2) inhibitors were investigated. Co‐administration of the ATR inhibitor (ATRi) BAY1895344 (BAY) and MEK1/2 inhibitors, for example, cobimetinib, synergistically increased cell death in diverse MM cell lines. Mechanistically, BAY and cobimetinib blocked STAT3 Tyr705 and Ser727 phosphorylation, respectively, and dual dephosphorylation triggered marked STAT3 inactivation and downregulation of STAT3 (Signal transducer and activator of transcription 3) downstream targets (c‐Myc and BCL‐XL). Similar events occurred in highly bortezomib‐resistant (PS‐R) cells, in the presence of patient‐derived conditioned medium, and with alternative ATR (e.g. M1774) and MEK1/2 (trametinib) inhibitors. Notably, constitutively active STAT3 c‐MYC or BCL‐XL ectopic expression significantly protected cells from BAY/cobimetinib. In contrast, transfection of cells with a dominant‐negative form of STAT3 (Y705F) sensitized cells to cobimetinib, as did ATR shRNA knockdown. Conversely, MEK1/2 knockdown markedly increased ATRi sensitivity. The BAY/cobimetinib regimen was also active against primary CD138+ MM cells, but not normal CD34+ cells. Finally, the ATR inhibitor/cobimetinib regimen significantly improved survival in MM xenografts, including bortezomib‐resistant models, with minimal toxicity. Collectively, these findings suggest that combined ATR/MEK1/2 inhibition triggers dual STAT3 Tyr705 and Ser727 dephosphorylation, pronounced downregulation of cytoprotective targets and MM cell death, warranting attention as a novel therapeutic strategy in MM. [ABSTRACT FROM AUTHOR]

Background and Purpose Experimental Approach Key Results Conclusion and Implications Sarcoplasmic reticulum Ca2+‐ATPase (SERCA2a) is impaired in heart failure. Phosphodiesterases (PDEs) are implicated in the modulation of local cAMP signals and protein kinase A (PKA) activity essential for cardiac function. We characterise PDE isoforms that underlie decreased activities of SERCA2a and reduced cardiac contractile function in diabetic cardiomyopathy.Wild type mice were fed with either normal chow or a high‐fat diet (HFD). Cardiomyocytes were isolated for excitation–contraction coupling (ECC), fluorescence resonant energy transfer PKA biosensor and proximity ligation assays.The upregulated PDE4D3 and PDE4D9 isoforms in HFD cardiomyocytes specifically bound to SERCA2a but not ryanodine receptor 2 (RyR2) on the sarcoplasmic reticulum (SR). The increased association of PDE4D isoforms with SERCA2a in HFD cardiomyocytes led to reduced local PKA activities and phosphorylation of phospholamban (PLB) but minimally effected the PKA activities and phosphorylation of RyR2. These changes correlate with slower calcium decay tau in the SR and attenuation of ECC in HFD cardiomyocytes. Selective inhibition of PDE4D3 or PDE4D9 restored PKA activities and phosphorylation of PLB at the SERCA2a complex, recovered calcium decay tau, and increased ECC in HFD cardiomyocytes. Therapies with PDE4 inhibitor roflumilast, PDE4D inhibitor BPN14770 or genetical deletion of PDE4D restored PKA phosphorylation of PLB and cardiac contractile function.The current study identifies upregulation of specific PDE4D isoforms that selectively inhibit SERCA2a function in HFD‐induced cardiomyopathy, indicating that this remodelling can be targeted to restore cardiac contractility in diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Endothelial dysfunction and pathological alterations are pivotal in the pathogenesis of cardiovascular disease. To date, effective interventions for these endothelial changes are lacking. Tumor necrosis factor‐alpha (TNF‐α) is known to significantly contribute to these alterations. It has been reported the potential of luteolin to mitigate TNF‐α‐induced inflammation, yet its specific mechanisms and targets still remain to be elucidated. This study aims to investigate the effects and mechanisms of luteolin on TNF‐α‐induced inflammatory injury in human microvascular endothelial cells, thereby advancing the understanding of luteolin's medicinal properties. Our findings demonstrate that luteolin notably inhibits TNF‐α‐induced phosphorylation of Akt, mitogen activated protein kinase (MAPK), and the nuclear factor‐kappaB (NF‐κB) p65. It significantly reduces the transcriptional activity of NF‐κB p65 and AP‐1 and decreases the expression of mRNA and proteins related to adhesion molecules and inflammatory mediators. Additionally, luteolin inhibited the reduction in STAT3 phosphorylation. In conclusion, luteolin effectively suppresses TNF‐α‐induced inflammatory injury in endothelial cells via the Akt/MAPK/NF‐κB pathway. [ABSTRACT FROM AUTHOR]

c‐Jun N‐terminal kinases (JNKs) including JNK1/2/3 are key members of mitogen‐activated protein kinase family. Wherein JNK3 is specifically expressed in brain and emerges as therapeutic target, especially for neurodegenerative diseases. However, developing JNK3 selective inhibitors as chemical probes to investigate its therapeutic potential in diseases remains challenging. Here, we adopted the covalent strategy for identifying JNK3‐selective covalent inhibitor JC16I, with high inhibitory activity against JNK3. Despite targeting a conserved cysteine in the vicinity of ATP pocket in JNK family, JC16I exerted a greater than 160‐fold selectivity for JNK3 over JNK1/2. Importantly, even at low concentration, JC16I showed enhanced and long‐lasting inhibition against cellular JNK3. In addition, its alkyne‐containing probe JC‐P1 could label JNK3 in SH‐SY5Y cell lysate and living cells, with good proteome‐wide selectivity. JC16I selectively suppressed the abnormal activation of JNK3 signaling and sufficiently exhibited neuroprotective effect in Parkinson's diseases (PD) models. Overall, our findings highlight the potential of developing isoform‐selective and cell‐active JNK3 inhibitors by covalent drug design strategy targeting a conserved cysteine. This work not only provides a valuable chemical probe for JNK3‐targeted investigations in vitro and in vivo but also opens new avenues for the treatment of PD. [ABSTRACT FROM AUTHOR]

Dysfunction of the alveolar endothelial barrier plays a crucial role in the pathogenesis of septic acute lung injury (ALI). orexin B is a neuropeptide derived from orexin neurons in the lateral hypothalamus and has multiple biological functions. However, the physiological function of orexin B in sepsis is less reported. Here, we aimed to explore the protective effects of orexin B in sepsis‐induced ALI and its underlying mechanisms. In this study, we established an ALI in vivo animal model in mice using cecal ligation and puncture (CLP) and an in vitro ALI model using mouse lung microvascular endothelial cells (MLMECs) induced with lipopolysaccharides (LPS). The animal experiments involved four groups: Sham, Sham+orexin B, CLP, CLP+orexin B. First, our results demonstrate that the levels of serum orexin B but not orexin A were reduced in septic mice. Correspondingly, the expression of orexin type 2 receptor (OX2R), but not orexin type 1 receptor (OX1R), was reduced in the lung tissue of septic mice. Administration of orexin B decreased the mortality in sepsis mice and improved M‐CASS scores. Hematoxylin–eosin (H&E) staining assay demonstrated that administration of orexin B ameliorated histopathological lung injury. orexin B was also found to inhibit the inflammatory response in the lung tissues of septic mice by reducing the expression of tumor necrosis factor α (TNF‐α), interleukin 6 (IL‐6), and recombinant chemokine C‐X‐C‐motif ligand 15 (CXCL15). Additionally, the total cell count and neutrophils in bronchoalveolar lavage fluid (BALF) were reduced by orexin B. Notably, orexin B alleviated vascular endothelial permeability in mice lung tissue by increasing the expression of the tight junction protein zonula occludens‐1 (ZO‐1) and occludin. In vitro experiments demonstrated that orexin B prevented LPS‐induced endothelial permeability in mouse lung microvascular endothelial cells (MLMECs) by upregulating the expression of ZO‐1 and occludin. These effects are mediated by rho‐associated coiled‐coil containing protein kinase 2 (ROCK2). Based on these findings, we conclude that orexin B alleviates sepsis‐induced ALI by ameliorating endothelial permeability of lung microvascular endothelial cells. [ABSTRACT FROM AUTHOR]

With the development of metalloimmunology, the potential of platinum drugs in cancer immunotherapy has attracted extensive attention. Although immunochemotherapy combining PD‐1/PD−L1 antibodies with platinum drugs has achieved great success in the clinic, combination therapy commonly brings new problems. Herein, we have developed a platinum‐metformin conjugate as a promising alternative to antibody‐based PD−L1 inhibitors, not only disrupting PD‐1/PD−L1 axis on cell surface but also down‐regulating the total PD−L1 levels in non‐small cell lung cancer (NSCLC) cells comprehensively, thus achieving highly efficient immunochemotherapy by a single small molecule. Mechanism studies demonstrate that Pt‐metformin conjugate can selectively accumulate in lysosomes, promote lysosomal‐dependent PD−L1 degradation via the AMPK‐TFEB pathway, and modulate the upstream regulatory proteins related to PD−L1 expression (e.g. HIF‐1α and NF‐κB), eventually decreasing the total abundance of PD−L1 in NSCLC, overcoming tumor hypoxia, and activating anti‐tumor immunity in vivo. This work suggests an AMPK‐mediated lysosomal degradation pathway of PD−L1 for the first time and provides a unique design perspective for the development of novel platinum drugs for immunochemotherapy. [ABSTRACT FROM AUTHOR]

Background: Alternative splicing is a fundamental mechanism in the post‐transcriptional regulation of genes. The multifunctional transmembrane glycoprotein receptor carcinoembryonic antigen‐related cell adhesion molecule 1 (CEACAM1) undergoes extensive alternative splicing to allow for tunable functions in cell signalling, adhesion and modulation of immune and metabolic responses. Splice isoforms that differ in their ectodomain and short or long cytoplasmic tail (CEACAM1‐S/CEACAM1‐L) have distinct functional roles. The mechanisms that regulate CEACAM1 RNA splicing remain elusive. Methods: This narrative review summarizes the current knowledge of the mechanism and function of CEACAM1 splice isoforms. Historical perspectives address the biological significance of the glycosylated Ig domains, the variable exon 7, and phosphorylation events that dictate its signal transduction pathways. The use of small antisense molecules to target mis‐spliced variable exon 7 is discussed. Results: The Ig variable‐like N domain mediates cell adhesion and immune checkpoint inhibitory functions. Gly and Tyr residues in the transmembrane (TM) domain are essential for dimerization. Calmodulin, Calcium/Calmodulin‐dependent protein kinase II delta (CamK2D), Actin and Annexin A2 are binding partners of CEACAM1‐S. Homology studies of the muCEACAM1‐S and huCEACAM1‐S TM predict differences in their signal transduction pathways. Hypoxia‐inducible factor 1‐α (HIF‐1‐α) induces alternative splicing to produce CEACAM1‐S under limited oxygen conditions. Antisense small molecules directed to exon 7 may correct faulty expression of the short and long cytoplasmic tail splicing isoforms. Conclusion: More pre‐clinical and clinical studies are needed to elucidate the precise mechanisms by which CEACAM1 RNA splicing may be exploited to develop targeted interventions towards novel therapeutic strategies. [ABSTRACT FROM AUTHOR]

Attention‐deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that involves dopaminergic dysfunction in the prefrontal cortex (PFC), manifesting hyperactivity, inattention, and cognitive deficits. However, the ADHD‐associated candidate genes underlying dopaminergic neurotransmission alterations remain poorly defined. Here, we identified the abundant localization of sodium‐calcium exchanger 3 (NCX3) levels in the dopaminergic neurons of the ventral tegmental area, a major source of dopaminergic innervation to the PFC. We confirmed that NCX3 knockdown in N27 cells caused aberrant dopamine influx through the strong interaction between calcium/calmodulin‐dependent protein kinase II alpha and dopamine transporter. In addition, we assessed behavioral changes and underlying molecular properties in NCX3 heterozygous (NCX3+/−) mice. NCX3+/− mice exhibited hyperactivity, cognitive deficits, and social dysfunction which were alleviated by treating with methylphenidate. Furthermore, NCX3+/− mice displayed a persistent elevation of basal dopamine levels and decreased extracellular levels of dopamine triggered by social stimuli in the PFC of NCX3+/− mice. In agreement with the rise in extracellular dopamine levels in the PFC, NCX3+/− mice showed activation of dopamine D1 receptor signaling pathways in the PFC compared to wild‐type mice. Thus, deficiency of NCX3 leads to impaired dopaminergic neurotransmission in the PFC, which likely accounts for the ADHD‐like behavior in NCX3+/− mice. [ABSTRACT FROM AUTHOR]

Melatonin, the hormone of the pineal gland, possesses a range of physiological functions, and recently, its anticancer effect has become more apparent. A more thorough understanding of molecular alterations in the components of several signaling pathways as new targets for cancer therapy is needed because of current innate restrictions such as drug toxicity, side effects, and acquired or de novo resistance. The PI3K/Akt/mTOR pathway is overactivated in many solid tumors, such as breast and ovarian cancers. This pathway in normal cells is essential for growth, proliferation, and survival. However, it is an undesirable characteristic in malignant cells. We have reviewed multiple studies about the effect of melatonin on breast and ovarian cancer, focusing on the PI3K/Akt/mTOR pathway. Melatonin exerts its inhibitory effects via several mechanisms. A: Downregulation of downstream or upstream components of the signaling pathway such as phosphatase and tensin homolog (PTEN), phosphatidylinositol (3,4,5)‐trisphosphate kinase (PI3K), p‐PI3K, Akt, p‐Akt, mammalian target of rapamycin (mTOR), and mTOR complex1 (mTORC1). B: Apoptosis induction by decreasing MDM2 expression, a downstream target of Akt, and mTOR, which leads to Bad activation in addition to Bcl‐XL and p53 inhibition. C: Induction of autophagy in cancer cells via activating ULK1 after mTOR inhibition, resulting in Beclin‐1 phosphorylation. Beclin‐1 with AMBRA1 and VPS34 promotes PI3K complex I activity and autophagy in cancer cells. The PI3K/Akt/mTOR pathway overlaps with other intracellular signaling pathways and components such as AMP‐activated protein kinase (AMPK), Wnt/β‐catenin, mitogen‐activated protein kinase (MAPK), and other similar pathways. Cancer therapy can benefit from understanding how these pathways interact and how melatonin affects these pathways. [ABSTRACT FROM AUTHOR]

Brain‐derived neurotrophic factor (BDNF), which is primarily expressed in the brain and nervous tissues, is the most abundant neurotrophic factor in the adult brain. BDNF serves not only as a major neurotrophic signaling agent in the human body but also as a crucial neuromodulator. Widely distributed throughout the central nervous system (CNS), both BDNF and its receptors play a significant role in promoting neuronal survival and growth, thereby exerting neuroprotective effects. It is further considered as a guiding medium for the functionality and structural plasticity of the CNS. Increasingly, research has indicated the critical importance of BDNF in understanding human diseases. Activation of intracellular signaling pathways such as the mitogen‐activated protein kinase pathway, phosphatidylinositol 3‐kinase/protein kinase B/mammalian target of rapamycin pathway, and phospholipase C γ pathway by BDNF can all potentially enhance the growth, survival, proliferation, and migration of cancer cells, influencing cancer development. The loss of BDNF and its receptor, tropomyosin receptor kinase B, in signaling pathways is also associated with increased susceptibility to brain and heart diseases. Additionally, reduced BDNF levels in both the central and peripheral systems have been closely linked to various neurogenic diseases, including neuropathic pain and psychiatric disorders. As such, this review summarizes and analyzes the impact of BDNF on neurogenic diseases, cancer, and cardiovascular diseases. This study thereby aimed to elucidate its effects on these diseases to provide new insights and approaches for their treatment. [ABSTRACT FROM AUTHOR]

SUMMARY: Gametocidal (Gc) chromosomes have been widely utilized in genetic breeding due to their ability to induce chromosomal breakage and eliminate gametes that lack them. Long noncoding RNAs (lncRNAs) have various functional mechanisms in regulating pollen and anther development; however, their regulatory contributions to Gc action are still unknown. Here, we identified 2824 differentially expressed lncRNAs (DE‐lncRNAs) from the anther tissues of Triticum aestivum cv. Chinese Spring (CS) and Chinese Spring‐Gc 3C chromosome monosomic addition line (CS‐3C) through sequencing. In this study, we predicted 161 target mRNAs for 145 DE‐lncRNAs, including 104 cis‐regulatory, 60 trans‐regulatory, and three both cis‐regulatory and trans‐regulatory manner. Combined with our previous miRNA sequencing data, 241 DE‐lncRNAs functioned as potential endogenous target mimics (eTMs) for 84 differentially expressed microRNAs (DE‐miRNAs, including 12 novel miRNAs). The results of transient transformation in tobacco leaves indicated that L006278 could bind to MTCONS_00006277, which encoded a calcineurin CBL‐interacting protein kinase 19‐like, and suppress its expression. Furthermore, L117735 could function as an eTM for tae‐miR9657b‐3p, and L056972 could function as an eTM for gc‐m2240‐5p. To explore the function of lncRNAs in the process of Gc action, we transformed L006278, an up‐regulated lncRNA in CS‐3C, into rice to analyze its effect on pollen fertility. Overexpression of L006278 led to a reduction in rice pollen fertility. Overall, our findings indicate that lncRNAs can contribute to the regulation of pollen fertility during the process of Gc action by regulating the expression levels of target mRNAs and acting as eTMs for certain key miRNAs. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome (SFTS) is a severe emerging infectious disease caused by Dabie bandavirus (DBV). Tectorigenin has been demonstrated to exert anti‐inflammatory effect. Here, we aimed to investigate the effects of tectorigenin on DBV‐induced cytokine storm. Effects of tectorigenin on cytokines in DBV‐infected THP‐1 cells and plasma samples of Type I interferon receptor (IFNAR)−/− mice infected with DBV were detected. The changes in body weight and survival time of mice were recorded. The liver, spleen, kidney, and lymph node tissues were collected for hematoxylin–eosin staining. We demonstrated that tectorigenin reduced the expression levels of inflammatory cytokines in both DBV‐infected THP‐1 cells and plasma samples of IFNAR−/− mice infected with DBV. Tectorigenin attenuated DBV‐induced histopathological changes in mice. Mechanistically, tectorigenin attenuated DBV‐induced phosphorylation of inhibitor of kappa‐B kinase alpha/beta (IKKα/β) of the nuclear factor‐κB (NF‐κB) signaling pathway, extracellular signal–regulated kinase (ERK) of the mitogen‐activated protein kinase (MAPK) signaling pathway and might function by downregulation of Toll‐like receptor. The result of this study suggested that tectorigenin exerted anti‐inflammatory effects in vivo and in vitro and could serve as a novel potential therapeutic strategy for SFTS. [ABSTRACT FROM AUTHOR]

The edible flower of Hemerocallis citrina Baroni, commonly known as "Huang Huacai" in China, has anti‐depressant effects. However, targets and molecular mechanisms of Hemerocallis citrina Baroni edible flowers (HEF) in depression treatment are still unclear. The potential anti‐depression targets in HEF were identified by the intersecting results from typical drug databases. The network construction and Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis were carried out for core targets. The molecular docking was conducted to predict the binding affinity between the active components and the central targets. The intersecting results indicated that there were 24 active components in HEF, with 449 anti‐depression targets identified. After screening through degree centrality (DC), betweenness centrality (BC), and closeness centrality (CC), 166 core targets were determined. Tumor protein 53 (TP53) and interleukin 6 (IL‐6) had the highest degree values. The results of GO enrichment analysis associated with anti‐depression revealed that the biological processes were negative regulation of osteoclast differentiation and positive regulation of phosphorus metabolic process. KEGG enrichment analysis results revealed that pathways, such as the phosphatidylinositol 3‑kinase‐protein kinase B (PI3K‐Akt) signaling pathway and mitogen‐activated protein kinase (MAPK) signaling pathway, were primarily associated with anti‐depression. Molecular docking results indicated that the top 10 active ingredients in HEF could bind to the central targets. This study applied network pharmacology to unveil the potential anti‐depressive mechanisms of HEF, providing a theoretical basis for further exploration of the effective components in H. citrina edible flower parts. [ABSTRACT FROM AUTHOR]

P38 mitogen‐activated protein kinases are key in the regulation of the cellular response to stressors. P38 is known to regulate transcription, mRNA processing, stability, and translation. The transcriptional changes mediated by phosphorylated p38 (P‐p38) in response to extracellular stimuli have been thoroughly analyzed in many tissues and organisms. However, the genomic localization of chromatin‐associated P‐p38 remains poorly understood. Here, we analyze the chromatin binding of activated P‐p38 and its role in the response to reactive oxygen species (ROS) in Drosophila S2 cells. We found that P‐p38 is already bound to chromatin in basal conditions. After ROS exposure, chromatin‐associated P‐p38 relocates towards genes involved in the recovery process. Our findings highlight the role of P‐p38 dynamic chromatin binding in orchestrating gene expression responses to oxidative stress. [ABSTRACT FROM AUTHOR]

Heart failure (HF) remains a significant global health concern with limited effective treatments available. C1q/TNF‐related protein 6 (CTRP6) is a member of the CTRP family analogous to adiponectin and its role in HF pathogenesis remains unclear. Here, we investigated the impact of CTRP6 on HF progression. To mimic heart failure with reduced ejection fraction (HFrEF), we used isoproterenol injection in mice and administered adenovirus vectors expressing CTRP6 (Ad‐CTRP6) via tail vein injection. We assessed cardiac function through echocardiography and histology. CTRP6's effects on hypertrophy, fibrosis, apoptosis, oxidative stress and mitochondrial function were analysed. Downstream pathways (phosphorylated AMP‐activated protein kinase (p‐AMPK), sirtuin 1 (SIRT1) and peroxisome proliferator‐activated receptor γ coactivator 1‐α (PGC‐1α) were studied in heart tissues. In vitro, isoproterenol‐stimulated H9c2 cardiomyocytes were treated with CTRP6 to examine viability, apoptosis, F‐actin and signalling proteins. Compound C was used to assess AMPK involvement. CTRP6 expression was lower in the plasma of HF patients. In an isoproterenol‐induced HFrEF mouse model, adenovirus‐mediated overexpression of CTRP6 ameliorated cardiac dysfunction and reduced cardiomyocyte apoptosis, oxidative stress, inflammation and myocardial injury markers. Mechanistically, CTRP6 activation of the AMPK/SIRT1/PGC‐1α signalling pathway restored mitochondrial homeostasis, evidenced by reduced mitochondrial reactive oxygen species levels, increased ATP content, and enhanced mitochondrial complex I/III activities in cardiac tissues. In vitro studies using isoproterenol‐stimulated H9c2 cardiomyocytes corroborated these findings, demonstrating that CTRP6 upregulation attenuated hypertrophy, apoptosis, oxidative stress and mitochondrial dysfunction. Furthermore, these effects were partially reversed by the AMPK inhibitor Compound C, implicating the involvement of the AMPK pathway in CTRP6‐mediated cardioprotection. CTRP6 alleviates HF progression through the AMPK/SIRT1/PGC‐1α signalling pathway. What is the central question of this study?What are the role and mechanisms of C1q/tumour necrosis factor‐related protein‐6 (CTRP6) in heart failure (HF) progression and its potential cardioprotective effects?What is the main finding and its importance?CTRP6 alleviates HF progression through the activation of the AMPK/SIRT1/PGC‐1α signalling pathway, reducing oxidative stress, inflammation and mitochondrial dysfunction. This may enable development of novel therapeutic strategies for HF management. [ABSTRACT FROM AUTHOR]

Background: As a commonly identified cancer in clinics, pancreatic cancer (PC) has poor prognostic outcomes. This work focused on clarifying the association between MIR‐766‐3P expression and PC development and progression, as well as the possible role as a biomarker in PC. Methods: MIR‐766‐3P expression within the human PC cells and samples was measured through miRNA RT‐PCR. The gene levels regulated by MIR‐766‐3P were analyzed through western blot (WB) and qRT‐PCR. To analyze whether MIR‐766‐3P was of certain significance in in vitro and in vivo PC cell proliferation, stemness, and cell cycle progression, the gain/loss‐of‐function assays were performed. Bioinformatics, RNA sequencing (RNA‐seq), and luciferase reporter assay were conducted for exploring regulatory role of MIR‐766‐3P/MAPK1/MAPK/ERK signal axis in PC. Result: In comparison with the normal controls, MIR‐766‐3P expression markedly decreased the tissues and cells of PC. Furthermore, MIR‐766‐3P could remarkably inhibit the proliferation, stemness, cell cycle progression, and development of PC. The analyses using RNA‐seq, and dual‐luciferase examination showed that MIR‐766‐3P could directly target mitogen‐activated protein kinase 1 (MAPK1). According to Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, MIR‐766‐3P could affect PC malignant phenotype by MAPK1 and the regulation of the MAPK/ERK‐related pathway. Conclusion: MIR‐766‐3P has a certain impact on PC malignant phenotype through combining with MAPK1 while regulating MAPK/ERK‐related pathway in vitro and in vivo. [ABSTRACT FROM AUTHOR]

As a chromatin remodelling factor, high mobility group A1 (HMGA1) plays various roles in both physiological and pathological conditions. However, its role in DNA damage response and DNA damage‐based chemotherapy remains largely unexplored. In this study, we report the poly ADP‐ribosylation (PARylation) of HMGA1 during DNA damage, leading to desensitization of esophageal squamous cell carcinoma (ESCC) cells to the poly(ADP‐ribose) polymerase 1 (PARP1) inhibitor, olaparib. We found that HMGA1 accumulates at sites of DNA damage, where it interacts with PARP1 and undergoes PARylation at residues E47 and E50 in its conserved AT‐hook domain. This modification enhances the accumulation of Ku70/Ku80 at the site of DNA damage and activates the DNA‐dependent protein kinase catalytic subunit, facilitating nonhomologous end‐joining repair. In both subcutaneous tumour models and genetically engineered mouse models of in situ esophageal cancer, HMGA1 interference increased tumour sensitivity to olaparib. Moreover, HMGA1 was highly expressed in ESCC tissues and positively correlated with PARP1 levels as well as poor prognosis in ESCC patients. Taken together, these findings reveal a mechanistic link between HMGA1 and PARP1 in regulating cell responses to DNA damage and suggest that targeting HMGA1 could be a promising strategy to increase cancer cell sensitivity to olaparib. [ABSTRACT FROM AUTHOR]

Drought stress is a common abiotic challenge that profoundly impacts plant growth and development. As sessile organisms, plants rely on various physiological and morphological adaptations to cope with drought conditions. The CIPK (calcineurin B‐like protein‐interacting protein kinase) family proteins play a pivotal role in mediating plant responses to abiotic stress through modulation of cellular membrane events via the CBL‐CIPK complex. However, reports documenting the CIPKs' regulation of non‐membrane events are scant. In this study, we discovered a novel subcellular localisation pattern of the AtCIPK20 protein of Arabidopsis, specifically to cortical microtubules (cMT), which is distinct from previously reported localisation patterns of plant CIPKs. AtCIPK20 regulates ABA‐induced loss of cMT organisation in guard cells, thereby facilitating stomatal closure, mitigating leaf water loss, and protecting plants from drought stress in Arabidopsis. The C‐terminal regulatory domain of AtCIPK20 governs its cMT targeting, whereas the interaction of AtCIPK20 with its CBL partners disrupts this localisation. Notably, the cMT targeting characteristic of AtCIPK20 is not exclusive, as several other CIPK members in Arabidopsis, maize, and rice exhibit similar localisation patterns. These findings broaden our current understanding of the role of plant CIPK members in abiotic stress resistance and suggest that future exploration of CIPK molecular functions should adopt a more comprehensive perspective. Summary statement: AtCIPK20 localises to the cortical microtubules, a subcellular distribution feature disrupted by its interactions with CBL partners. It regulates microtubule depolymerization mediated by ABA, thereby promoting stomatal closure and positively modulating Arabidopsis drought resistance. [ABSTRACT FROM AUTHOR]

The mitogen‐activated protein kinase (MAPK) cascade (MAPKKK‐MAPKK‐MAPK) plays a critical role in biotic and abiotic stress responses and abscisic acid (ABA) signalling. A previous study has shown that the ABA‐activated MKK1‐MPK1 cascade is essential in regulating ABA response and stress tolerance in rice. However, the specific MAPKKK upstream of the MKK1‐MPK1 cascade in ABA signalling remains unknown. Here, we identified that MAPKKK28, a previously uncharacterized member of the rice MEKK family, is involved in regulating ABA responses, including seed germination, root growth, stomatal closure, and the tolerance to oxidative stress and osmotic stress. We found that MAPKKK28 directly interacts with and phosphorylates MKK1. Further analysis indicated that the activation of both MKK1 and MPK1 depends on MAPKKK28 in ABA signalling. Genetic analysis revealed that MAPKKK28 functions upstream of the MKK1‐MPK1 cascade to positively regulate ABA responses and enhance tolerance to oxidative and osmotic stress. These results not only reveal a new complete MAPK cascade in plants but also uncover its importance in ABA signalling. Summary statement: This manuscript demonstrated that MAPKKK28, a previously uncharacterized mitogen‐activated protein kinase kinase kinase in rice, functions upstream of the MKK1‐MPK1 cascade to positively regulate abscisic acid responses and the tolerance to oxidative stress and osmotic stress. [ABSTRACT FROM AUTHOR]

Cold stress negatively impacts the growth, development, and quality of Camellia sinensis (Cs, tea) plants. CBL‐interacting protein kinases (CIPK) comprise a pivotal protein family involved in plant development and response to multiple environmental stimuli. However, their roles and regulatory mechanisms in tea plants (Camellia sinensis (L.) O. Kuntze) remain unknown. Here we show that CsCBL‐interacting protein kinase 11 (CsCIPK11), whose transcript abundance was significantly induced at low temperatures, interacts and phosphorylates tau class glutathione S‐transferase 23 (CsGSTU23). CsGSTU23 was also a cold‐inducible gene and has significantly higher transcript abundance in cold‐resistant accessions than in cold‐susceptible accessions. CsCIPK11 phosphorylated CsGSTU23 at Ser37, enhancing its stability and enzymatic activity. Overexpression of CsCIPK11 in Arabidopsis thaliana resulted in enhanced cold tolerance under freezing conditions, while transient knockdown of CsCIPK11 expression in tea plants had the opposite effect, resulting in decreased cold tolerance and suppression of the C‐repeat‐binding transcription factor (CBF) transcriptional pathway under freezing stress. Furthermore, the transient overexpression of CsGSTU23 in tea plants increased cold tolerance. These findings demonstrate that CsCIPK11 plays a central role in the signaling pathway to cold signals and modulates antioxidant capacity by phosphorylating CsGSTU23, leading to improved cold tolerance in tea plants. Summary Statement: CsCIPK11 decodes cold signals and modulates antioxidant capacity by phosphorylating CsGSTU23, leading to improved cold tolerance in tea plants. CsCIPK11‐ CsGSTU23 module regulates cold tolerance in tea plant and supplies gene resources for cold‐resistant tea cultivar breeding. [ABSTRACT FROM AUTHOR]

Several studies have implicated the L3 auditory interneuron in the regulation of syllable period selective phonotaxis in female cricket Acheta domesticus. The L3's response to model calls of conspecific males comprises of an immediate and a prolonged response. The kinetics of activation of these electrical activities are consistent with sequential activation of ionotropic and metabotropic mechanisms. In this study, we used electrophysiological and pharmacological tools to investigate the cellular mechanisms underlying L3's response. Bath application of the synthetic protein kinase inhibitor 1‐(5‐isoquinolinesul‐fonyl)‐2‐methylpiperazine (H7), results in the suppression of L3's spiking response, and this effect can be reversed by saline wash. Additionally, when female A. domesticus that were previously nano‐injected with H7 were tested for phonotaxis on a non‐compensating treadmill, they demonstrated suppression of syllable period‐dependent phonotaxis. These findings implicate protein kinase in the regulation of L3's spiking rhythm and the associated phonotaxis in A. domesticus. [ABSTRACT FROM AUTHOR]

Introduction: Arrhythmia occurs as a common heart vascular disease. Functional food is a rich source of natural compounds with significant pharmacological, The aim of this paper is to explore its effect on arrhythmia. Methods: By reviewing the literature and summarising the findings, we described the role of functional foods in the alleviation of cardiac arrhythmias from different perspectives. Results: Our study shows that functional foods have anti‐arrhythmic effects through modulation of ion channels, oxidative stress, and Calmodulin‐dependent protein kinase II. Conclusions: We summarize the mechanism of arrhythmia inhibition by the active ingredients of medicinal diets in this review article, intending to provide research ideas for dietary therapy to regulate arrhythmia. [ABSTRACT FROM AUTHOR]

Symbiotic microorganisms are essential for the physiological processes of herbivorous pests, including the pear lace bug Stephanitis nashi, which is known for causing extensive damage to garden plants and fruit trees due to its exceptional adaptability to diverse host plants. However, the specific functional effects of the microbiome on the adaptation of S. nashi to its host plants remains unclear. Here, we identified significant microbial changes in S. nashi on 2 different host plants, crabapple and cherry blossom, characterized by the differences in fungal diversity as well as bacterial and fungal community structures, with abundant correlations between bacteria or fungi. Consistent with the microbiome changes, S. nashi that fed on cherry blossom demonstrated decreased metabolites and downregulated key metabolic pathways, such as the arginine and mitogen‐activated protein kinase signaling pathway, which were crucial for host plant adaptation. Furthermore, correlation analysis unveiled numerous correlations between differential microorganisms and differential metabolites, which were influenced by the interactions between bacteria or fungi. These differential bacteria, fungi, and associated metabolites may modify the key metabolic pathways in S. nashi, aiding its adaptation to different host plants. These results provide valuable insights into the alteration in microbiome and function of S. nashi adapted to different host plants, contributing to a better understanding of pest invasion and dispersal from a microbial perspective. [ABSTRACT FROM AUTHOR]

Pneumonia is a serious and life‐threatening lung inflammation with high morbidity and mortality. Accumulating evidence has suggested that esculin, a derivative of coumarin, possesses potent anti‐inflammatory effects. This study is designed to explore the pharma role and underlying mechanism of esculin against lipopolysaccharides (LPS)‐induced pneumonia. TC‐1 cells were stimulated by LPS to mimic the inflammatory injury model in vitro. Cell viability, proliferation, and apoptosis were determined using MTT assay, 5‐ethynyl‐2′‐deoxyuridine assay, and flow cytometry. Interleukin‐1β and tumor necrosis factor α levels were analyzed using an enzyme‐linked immunosorbent assay. Reactive oxygen species and superoxide dismutase were examined using special assay kits. Macrophage polarization was detected using flow cytometry. Mitogen‐activated protein kinase 14 (MAPK14) level was detected by real‐time quantitative polymerase chain reaction. MAPK14 and ubiquitin‐specific protease 7 (USP7) protein levels were determined using western blot assay. After Ubibrowser database prediction, the interaction between USP7 and MAPK14 was verified using a Co‐immunoprecipitation assay. The biological role of esculin was verified in LPS‐challenged ALI mice in vivo. Here, we found that esculin significantly relieved LPS‐induced TC‐1 cell proliferation inhibition, and apoptosis, inflammatory response, oxidative stress, and M1‐type macrophage polarization promotion. MAPK14 and USP7 expressions were enhanced in LPS‐treated TC‐1 cells, which was partly abolished by esculin treatment. Overexpressing MAPK14 attenuated the repression of esculin on LPS‐triggered TC‐1 cell injury. At the molecular level, USP7 interacted with MAPK14 and maintained its stability by removing ubiquitin. Moreover, esculin repressed the progression of pneumonia in vivo by regulating MAPK14. Taken together, esculin exposure could mitigate LPS‐induced TC‐1 cell injury partly by targeting the USP7/MAPK14 axis, providing a better understanding of the role of esculin in the anti‐inflammatory therapeutics for pneumonia. Esculin treatment could relieve LPS‐induced TC‐1 cell proliferation inhibition, and apoptosis, inflammation, oxidative stress, macrophage M1 polarization promotion in vitro, as well as pneumonia progression in vivo by regulating the USP7/mitogen‐activated protein kinase 14 (MAPK14) axis. Furthermore, USP7 could facilitate protein stability and MAPK14 expression in TC‐1 cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: Protein kinases are a type of transferase enzyme that catalyze the phosphorylation of protein substrates, including receptor proteins. Testis‐specific serine/threonine kinases (TSSKs) are a highly conserved group of protein kinases found in various organisms. They play an essential role in male reproduction by influencing sperm development and function. RESULTS: In this study, we report on the characterization of BmTSSK3, a TSSK from the silkworm, Bombyx mori. We found that BmTSSK3 is specifically expressed in the testis and localized to the sperm flagella, particularly in the sperm tail cyst. Furthermore, we developed BmTSSK3 inhibitors through molecular docking and binding assays. Small molecules 5‐(4‐Fluorophenyl)‐2‐ureidothiophene‐3‐carboxamide (TPCA‐1) and Imidurea were identified to bind to BmTSSK3. Using site‐specific mutation technology, we identified amino acid residues R134 and S184 as crucial binding sites for small molecules. RNA interference assay and Western blot analysis showed that knockdown of BmTSSK3 significantly decreased histone 3 phosphorylation. To confirm the inhibitory effect of these small molecules, we treated silkworm testes with TPCA‐1 and observed a strong inhibitory effect. CONCLUSION: TPCA‐1 is an inhibitor of BmTSSK3, which raises its potential as a future candidate for male sterility of the silkworm. Thus, this study may offer a novel strategy for sterile silkworms as well as insects. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study aims to explore the role of Protein Kinase N2 (PKN2) in peripheral nerve injury (PNI) and evaluate its potential as a therapeutic target. The study employed a PC12 cell model to assess the effects of PKN2 overexpression on cell proliferation, migration, synaptic growth, and autophagic activity, with a focus on the regulatory role of the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway. The results demonstrated that PKN2 overexpression significantly promoted PC12 cell proliferation and cell migration, while also enhancing synaptic growth. Additionally, a significant suppression of autophagy was observed. Mechanistic analysis revealed that PKN2 inhibited autophagic activity through the activation of the AKT/mTOR pathway. In summary, PKN2 plays a significant role in peripheral nerve repair by promoting cell proliferation, migration, and synaptic growth, while inhibiting autophagy through the AKT/mTOR pathway. These findings suggest that targeting PKN2 may represent an effective therapeutic strategy for the treatment of PNI. [ABSTRACT FROM AUTHOR]

Summary Rice false smut disease, caused by the fungal pathogen Ustilaginoidea virens, significantly restricts both the production and quality of rice grains. However, the molecular mechanism underlying rice resistance against U. virens remain largely elusive. Transcriptome analysis of rice panicles infected with U. virens revealing the crucial role of genes involved in sakuranetin biosynthesis in conferring resistance to the pathogen. In vitro assays demonstrated that sakuranetin was most effective at inhibiting mycelial growth, spore germination, and host infection by U. virens. The expression of OsNOMT, the key enzyme in sakuranetin biosynthesis, is directly regulated by the transcription factor OsWRKY67. Furthermore, OsMPK6, a mitogen‐activated protein kinase, interacts with and phosphorylates OsWRKY67, thereby modulating sakuranetin biosynthesis and resistance to U. virens. Moreover, the exogenous application of synthetic sakuranetin significantly reduces U. virens infection. Our findings reveal that the OsMPK6‐OsWRKY67‐OsNOMT signaling cascade plays a pivotal role in rice resistance to U. virens by regulating sakuranetin biosynthesis. [ABSTRACT FROM AUTHOR]

The regulation of macrophage polarization by mesenchymal stem cells (MSCs) is a prominent area of research but faces challenges due to limited MSC sources and incomplete understanding of underlying mechanisms. We sought to identify an accessible MSC source and investigate how MSCs regulate macrophage polarization using high‐throughput sequencing. We isolated dental follicle MSCs from discarded human third molar dental follicles and cocultured them with THP‐1‐derived macrophages in the conditioned medium. Transcriptome sequencing identified differentially expressed genes (DEGs) in macrophages, integrating with multiomics database analysis to uncover polarization mechanisms. Our findings demonstrated successful MSC extraction from dental follicles, with the conditioned medium suppressing proinflammatory macrophage functions and influencing macrophage subtyping. MSCs, through paracrine signaling, activated the mitogen‐activated protein kinase (MAPK) pathway, leading to extracellular regulated protein kinases (ERK)1/2 phosphorylation and upregulation of early growth response 1 (EGR1) protein. Elevated EGR1 levels inhibited inflammatory gene expression, inhibiting the pro‐inflammatory immunoregulatory function of macrophages in inflammatory states. This study provides an efficient method for in vitro macrophage polarization identification. It offers insights into MSC‐regulated polarization mechanisms, with potential clinical implications for anti‐inflammatory therapy and immune regulation. [ABSTRACT FROM AUTHOR]

Cell division cycle 37 (CDC37) is a member of the molecular chaperone family and acts as a cochaperone of heat shock protein 90 (HSP90), which is overexpressed in many cancer types as a regulator of protein kinase maturation. In this process, CDC37 selectively recognizes and stabilizes protein kinases by forming a HSP90‐CDC37‐kinase chaperone complex. The protein‐protein interactions (PPIs) of HSP90‐CDC37 and CDC37‐kinase complexes contribute to malignant tumors, as oncogenic kinases in malignant cells depend upon CDC37 expression. Thus, inhibiting CDC37 to disrupt HSP90‐CDC37‐kinase chaperone complex reveals as a promising way to achieve selective inhibition of oncogenic kinase maturation. Herein, we report a small‐molecule CDC37 inhibitor called DDO‐6079 that simultaneously inhibits HSP90‐CDC37 and CDC37‐CDK4/6 chaperone complex by binding to an allosteric site on CDC37. DDO‐6079 selectively inhibited the maturation of multiple oncogenic kinases to escape heat shock response (HSR). Furthermore, DDO‐6079 decreased the thermostability of CDK6, reversed the resistance of CDK6 to palbociclib (a successful CDK4/6 inhibitor) in colorectal cancer cells and exhibited efficacy in vivo. Together, the results revealed that DDO‐6079 is a first‐in‐class small molecule CDC37 inhibitor that disrupts the HSP90‐CDC37‐kinase chaperone complex and provides a new way to block kinase maturation. [ABSTRACT FROM AUTHOR]

Radiotherapy‐induced ferroptosis is accompanied by an adaptive response to the expression of tumor cell ferroptosis suppressor genes. Herein, a degradable and in situ generated silicomanganese composite system loaded with carbonic anhydrase (CA IX) inhibitor (4‐(2‐aminoethyl) benzenesulfonamide (ABS) is constructed to form a DSiMn‐ABS nanosystem to improve the ferroptosis sensitivity of hypoxic tumor cells and improve the radiotherapy effect. The system can be continuously degraded in the tumor environment and X‐rays, releasing Manganese dioxid （MnO2)and ABS; Thereby inhibiting the activity of CA IX, inducing acidification inside tumor cells, regulating the AMP‐activating protein kinase (AMPK)/Acetyl‐CoA carboxylase(ACC) axis to increase the sensitivity of tumor cells to ferroptosis, and depleting glutathione (GSH) through MnO2 influencing glutathione peroxidase 4 (GPX4) activity, which further inhibits the ferroptosis defense system of tumor cells, and ultimately effectively improves the therapeutic efficiency of radiotherapy. Ultimately, the system can effectively inhibit tumor growth. Therefore, this degradable system can utilize double‐sensitized radiotherapy to provide new ideas for tumor radiotherapy. [ABSTRACT FROM AUTHOR]

The repair of hierarchical osteochondral defects requires complex gradient reconstruction at different levels, with continuous‐gradient mineralization being crucial. Strategies for achieving continuous‐gradient mineralization have rarely been reported. Here, a continuous‐gradient mineralized hydrogel is prepared using simple gravitational osmosis of a ≈2 nm amorphous calcium phosphate nanocluster (ACPC) suspension into composite organic frameworks for osteochondral regeneration. During gravitational infiltration, ACPC underwent gradual mineralization, resulting in the spontaneous formation of hydroxyapatite (HAP). The continuous‐gradient mineralized hydrogel aligned closely with the normal osteochondral structure, thereby effectively promoting repair of the cartilage and subchondral bone. In the cartilage layer, organic compounds improved the oxidative stress environment induced by injury and complemented the extracellular matrix of the cartilage. In the subchondral bone layer, HAP from the continuously mineralized hydrogel induced intracellular calcium accumulation in mesenchymal stem cells (MSCs), activating calcium/calmodulin‐dependent protein kinase 2 (CaMK2) and promoting osteogenic differentiation of MSCs through the calcium signaling pathway. Ultimately, compared with the nongradient hydrogel, this innovative gradient mineralization method exhibited significantly enhanced regeneration capabilities for osteochondral defects, as evidenced by metrics, such as bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N). This holistic strategy provides hope in the field of osteochondral repair. [ABSTRACT FROM AUTHOR]

Excessive fat accumulation and chronic inflammation are two typical characteristics of obesity. AMP‐activated protein kinase (AMPK), a master regulator of energy metabolism, is involved in adipogenesis, lipogenesis, and inflammation modulation in adipose tissue (AT). Thus, effective lipid reduction and anti‐inflammation through AMPK regulation play vital roles in treating obesity. Herein, an anti‐obesity nanosandwich is fabricated through attaching polymetformin (PolyMet) onto photothermal agent black phosphorus nanosheets (BP). PolyMet activates AMPK to inhibit adipogenesis, promote browning, and mitigate AT inflammation by decreasing macrophage infiltration, repolarizing macrophage phenotype, and downregulating pro‐inflammatory cytokines. Additionally, BP induces lipolysis and apoptosis of adipocytes and macrophages through a photothermal effect. By further functionalization using hyaluronic acid (HA) and MMP2 substrate‐linking P3 peptide‐modified HA (P3‐HA), an enhanced anti‐obesity effect is obtained by dual‐targeting of P3 and HA, and HA‐mediated CD44 poly‐clustering after MMP2 cleavage. Upon laser irradiation, the designed nanosandwich (P3‐HA/PM@BP) effectively inhibits obesity development in obese mice, increases M2/M1 ratio in AT, reduces the serum levels of cholesterol/triglyceride and improves insulin sensitivity, exhibiting promising research potential to facilitate the clinical development of modern anti‐obesity therapies. [ABSTRACT FROM AUTHOR]

Mixed lineage kinases (MLKs), comprising seven members: MLK1‐4, dual leucine zipper kinase (DLK), leucine zipper kinase (LZK), and sterile alpha motif and leucine zipper containing kinase (ZAK), belong to the mitogen‐activated protein kinase kinase kinase (MAP3K) family. These kinases are implicated in the progression of numerous cancers by activating mitogen‐activated protein kinase (MAPK) cascades or functioning as ser/thr and tyr kinases. However, their specific roles in glioma remain elusive. In the present study, we utilized bioinformatics approaches to investigate the expression patterns of MLKs in low‐grade gliomas (LGG) and glioblastoma multiforme (GBM). Additionally, we analyzed their clinical significance and delved into the potential mechanisms underlying MLK activity as well as their association with tumor‐immune infiltrating cells (TIICs) in glioma. Furthermore, we conducted in vitro studies to elucidate the functional roles of MLK1‐2 in glioma. Our findings revealed that the expressions of MLK1‐2 were conspicuously downregulated in GBM and positively correlated with patients' overall survival. Conversely, ZAK exhibited an opposing trend. Notably, our newly devised risk score model exhibited superior performance in predicting patient prognoses. Moreover, we analyzed the potential mechanisms of MLK activity and its interplay with tumor immune infiltration. Last, we validated the antitumor effect of MLK1‐2 at the in vitro level. In summary, our study sheds new insights into the roles of MLKs in glioma, particularly MLK1‐2, and their potential as therapeutic targets. [ABSTRACT FROM AUTHOR]

Summary Tanshinones, isolated from Salvia miltiorrhiza, is efficient to treat cardiovascular and cerebrovascular diseases. Abscisic acid (ABA) treatment is found to promote tanshinone biosynthesis; however, the underlying mechanism has not been fully elucidated. A protein kinase namely SmAPK1 was identified as an important positive regulator of ABA‐induced tanshinone accumulation in S. miltiorrhiza. Using SmAPK1 as bait, a basic region leucine zipper (bZIP) family transcription factor SmbZIP4 was screened from the cDNA library. Functional identification reveals that SmbZIP4 negatively regulates tanshinone biosynthesis in hairy roots and transgenic plants through directly targeting SmGGPPS and SmCYP76AK1. SmAPK1 phosphorylates the Ser97 and Thr99 site of SmbZIP4, leading to its degradation via the 26S proteasome pathway, which is promoted by ABA‐induced enhancement of SmAPK1 kinase activity. Degradation of SmbZIP4 upregulates the expression levels of SmGGPPS and SmCYP76AK1, resulting in increased tanshinone content. Taken together, our results reveal new molecular mechanism by which SmAPK1‐SmbZIP4 module plays a crucial role in ABA‐induced tanshinone accumulation. This study sheds new insights in the biosynthesis of bioactive compounds in medicinal plants. [ABSTRACT FROM AUTHOR]