Master Switch Research Articles

Jasmonate activates secondary cell wall biosynthesis through MYC2-MYB46 module.

Formation of secondary cell wall (SCW) is tightly regulated spatiotemporally by various developmental and environmental signals. Successful fine-tuning of the trade-off between SCW biosynthesis and stress responses requires a better understanding of how plant growth is regulated under environmental stress conditions. However, the current understanding of the interplay between environmental signaling and SCW formation is limited. The lipid-derived plant hormone jasmonate (JA) and its derivatives are important signaling components involved in various physiological processes including plant growth, development, and abiotic/biotic stress responses. Recent studies suggest that JA is involved in SCW formation but the signaling pathway has not been studied for how JA regulates SCW formation. We tested this hypothesis using the transcription factor MYB46, a master switch for SCW biosynthesis, and JA treatments. Both the transcript and protein levels of MYB46, a master switch for SCW formation, were significantly increased by JA treatment, resulting in the upregulation of SCW biosynthesis. We then show that this JA-induced upregulation of MYB46 is mediated by MYC2, a central regulator of JA signaling, which binds to the promoter of MYB46. We conclude that this MYC2-MYB46 module is a key component of the plant response to JA in SCW formation.

Cardiorespiratory adaptations in small cetaceans and marine mammals.

The dive response, or the 'master switch of life', is probably the most studied physiological trait in marine mammals and is thought to conserve the available O2 for the heart and brain. Although generally thought to be an autonomic reflex, several studies indicate that the cardiovascular changes during diving are anticipatory and can be conditioned. The respiratory adaptations, where the aquatic breathing pattern resembles intermittent breathing in land mammals, with expiratory flow exceeding 160litres s-1 has been measured in cetaceans, and where exposure to extreme pressures results in alveolar collapse (atelectasis) and recruitment upon ascent. Cardiorespiratory coupling, where breathing results in changes in heart rate, has been proposed to improve gas exchange. Cardiorespiratory coupling has also been reported in marine mammals, and in the bottlenose dolphin, where it alters both heart rate and stroke volume. When accounting for this respiratory dependence on cardiac function, several studies have reported an absence of a diving-related bradycardia except during dives that exceed the duration that is fuelled by aerobic metabolism. This review summarizes what is known about the respiratory physiology in marine mammals, with a special focus on cetaceans. The cardiorespiratory coupling is reviewed, and the selective gas exchange hypothesis is summarized, which provides a testable mechanism for how breath-hold diving vertebrates may actively prevent uptake of N2 during routine dives, and how stress results in failure of this mechanism, which results in diving-related gas emboli.

An Investigation of the JAZ Family and the CwMYC2-like Protein to Reveal Their Regulation Roles in the MeJA-Induced Biosynthesis of β-Elemene in Curcuma wenyujin.

β-Elemene (C15H24), a sesquiterpenoid compound isolated from the volatile oil of Curcuma wenyujin, has been proven to be effective for multiple cancers and is widely used in clinical treatment. Unfortunately, the β-elemene content in C. wenyujin is very low, which cannot meet market demands. Our previous research showed that methyl jasmonate (MeJA) induced the accumulation of β-elemene in C. wenyujin. However, the regulatory mechanism is unclear. In this study, 20 jasmonate ZIM-domain (JAZ) proteins in C. wenyujin were identified, which are the core regulatory factors of the JA signaling pathway. Then, the conservative domains, motifs composition, and evolutionary relationships of CwJAZs were analyzed comprehensively and systematically. The interaction analysis indicated that CwJAZs can form homodimers or heterodimers. Fifteen out of twenty CwJAZs were significantly induced via MeJA treatment. As the master switch of the JA signaling pathway, the CwMYC2-like protein has also been identified and demonstrated to interact with CwJAZ2/3/4/5/7/15/17/20. Further research found that the overexpression of the CwMYC2-like gene increased the accumulation of β-elemene in C. wenyujin leaves. Simultaneously, the expressions of HMGR, HMGS, DXS, DXR, MCT, HDS, HDR, and FPPS related to β-elemene biosynthesis were also up-regulated by the CwMYC2-like protein. These results indicate that CwJAZs and the CwMYC2-like protein respond to the JA signal to regulate the biosynthesis of β-elemene in C. wenyujin.

Manipulation of Stem Cell Fate In Vitro Using Plasmid-Based Transcription Factor Over-Expression Systems

Introduction: The ability to switch stem cell differentiation fate in-vitro, is a powerful tool that may allow the generation of large numbers of cells that may be required in order to develop biologically engineered tissues and cells required for therapeutic applications such as pharmacological testing of new medications. The transcription factor (“master switch”) Olig2, alone or in conjunction with Nkx2.2, has been implicated as a key cell fate decider for emerging neuro-glial precursors derived from both embryonic stem (ES) cells and from foetal neural stem (FNS) cells. Methods: The in-vitro system of stem cells devoid of exogenous signaling was developed. Stem cells were manipulated by pIRES plasmid vector driven, constitutively expressed Olig-2 or Olig-2/Nkx2.2 transcription factor system introduced into proliferating embryonic or foetal neural stem cells, following a similar embryological temporal p at te r ni n g s e q ue nc e s e e n i n -vi v o. Findings: Successful stem cell fate modification could be achieved in-vitro using the transcription factor overexpression system. Substantially different cell fates were noted in the presence of Olig-2 alone and in combination with Nkx2.2, with the achievement of premature glial differentiation. Conclusion: This method, therefore, may be useful to generate rare live human cells (such as Oligodendroglia or specialised myocardial cells) in-vitro.

The OsbHLH002/OsICE1-OSH1 module orchestrates secondary cell wall formation in rice

Transcriptional regulation of secondary cell wall (SCW) formation is strictly controlled by a complex network of transcription factors in vascular plants and has been shown to be mediated by a group of NAC master switches. In this study, we show that in a bHLH transcription factor, OsbHLH002/OsICE1, its loss-of-function mutant displays a lodging phenotype. Further results show that OsbHLH002 and Oryza sativa homeobox1 (OSH1) interact and share a set of common targets. In addition, the DELLA protein SLENDER RICE1, rice ortholog of KNOTTED ARABIDOPSIS THALIANA7, and OsNAC31 interact with OsbHLH002 and OSH1 and regulate their binding capacity on OsMYB61, a key regulatory factor in SCW development. Collectively, our results indicate OsbHLH002 and OSH1 as key regulators in SCW formation and shed light on molecular mechanisms of how active and repressive factors precisely orchestrate SCW synthesis in rice, which may provide a strategy for manipulating plant biomass production.

Jasmonates: “The Master Switch” for Regulation of Developmental and Stress Responses in Plants

Jasmonates: “The Master Switch” for Regulation of Developmental and Stress Responses in Plants

Phase I study of MP0317, a FAP-dependent DARPin, for tumor-localized CD40 activation in patients with advanced solid tumors.

2584 Background: CD40 is a master switch for both innate and adaptive immune systems. The clinical development of CD40 agonists has been hampered by dose-limiting toxicity (DLT) due to systemic CD40 activation and peripheral target-mediated drug disposition (TMDD). MP0317 is a CD40-agonistic DARPin (designed ankyrin repeat protein), developed to reduce systemic toxicity. MP0317 is exclusively active in the presence of fibroblast activating protein (FAP) expressed by cancer associated fibroblasts in the tumor microenvironment. This allows reaching serum levels that overcome the TMDD and have the potential to deliver sustained and tumor-localized CD40 activation. Ongoing clinical testing aims at establishing its safety/tolerability profile, PK/PD characteristics, and a recommended dose for combination therapy. Methods: NCT05098405 is a Phase 1, multicenter, open label, dose escalation study followed by a safety expansion part in adult patients with advanced solid tumors. The dose escalation scheme uses an adaptive Bayesian logistic regression model with overdose control. Peripheral blood biomarkers are analyzed by immuno-assays and flow cytometry, and baseline and on-treatment tumor biopsies are characterized by RNA sequencing and immunofluorescence. Eligible patients are enrolled into 9 sequentially escalating dose cohorts of MP0317 (0.03-10 mg/kg), administered IV 3-weekly (Q3W) or 1-weekly (Q1W) until disease progression or unacceptable toxicity. Results: At submission, 23 patients across 6 cohorts completed the study, with no DLT observed. Patient enrolling in higher dose cohorts is ongoing. The most frequent AE was grade 2 infusion related reaction in 5 patients. The 23 patients received ≥2 (range 2-8) doses (range 0.03 – 3 mg/kg) of MP0317 across five Q3W and one Q1W cohorts and completed the 28-day DLT period. PK data confirmed all patients were exposed to MP0317 with broadly dose-dependent Cmax and no sign of accumulation. PD data was derived from patients dosed with 0.03 – 3 mg/kg. Soluble biomarkers (sFAP and sCD40) showed target engagement in periphery with signs of FAP saturation at ≥0.5 mg/kg. Colocalization of MP0317 with FAP and CD40 in the tumor was confirmed in 4 out of 8 evaluable paired tumor biopsies. Whole transcriptome and gene set enrichment analyses showed an upregulation of genes related to B-cell trafficking (CXCL3, CXCR5, CCR6, CCL20) upon treatment. Transient increase of IFNg-induced chemokines (CXCL9, CXCL10) was observed, whereas the pro-inflammatory cytokines (TNFa, IL-2, IL-6, IL-8) were not upregulated. Conclusions: Clinical data and the lack of pro-inflammatory circulating cytokines confirm MP0317 is safe and well-tolerated, while analysis of paired pre- and on-treatment tumor biopsies suggests early evidence of tumor-localized CD40 activation. The current data enables further evaluation in a combination setting. Clinical trial information: NCT05098405 .

AtHDA15 attenuates COP1 via transcriptional quiescence, direct binding, and sub-compartmentalization during photomorphogenesis

Light is an essential environmental cue that determines the overall growth and development of plants. However, the molecular mechanisms underpinning the light signaling network are obscured by the epigenetic machinery where reversible acetylation and deacetylation play crucial roles in modulating light-regulated gene expression. In this paper, we demonstrate that HDA15 represses COP1, the master switch in the light signaling network, by deacetylation, protein interaction, and sub-compartmentalization. hda15 T-DNA mutant lines exhibited light hyposensitivity with significantly reduced HY5 and PIF3 transcript levels leading to long-hypocotyl phenotypes in the dark while its overexpression exhibited elevated HY5 transcripts and short hypocotyl phenotypes. In vivo and in vitro binding assays further show that HDA15 directly interacts with COP1 inside the nucleus modulating COP1’s repressive activities. Crossing hda15-t27 with cop1-4 mutants resulted in short-hypocotyl and dwarfed phenotypes, reminiscent of cop1-4 mutants suggesting COP1 is epistatic to HDA15. Although light signals the nucleocytoplasmic shuttling of HDA15, the presence of COP1 triggers its nuclear localization. A working model is presented elucidating the concerted interplay between HDA15 and COP1 under light and dark conditions.

Clock-regulated coactivators selectively control gene expression in response to different temperature stress conditions in Arabidopsis

Plants respond to severe temperature changes by inducing the expression of numerous genes whose products enhance stress tolerance and responses. Dehydration-responsive element (DRE)-binding protein 1/C-repeat binding factor (DREB1/CBF) transcription factors act as master switches in cold-inducible gene expression. Since DREB1 genes are rapidly and strongly induced by cold stress, the elucidation of the molecular mechanisms of DREB1 expression is vital for the recognition of the initial responses to cold stress in plants. A previous study indicated that the circadian clock-related MYB-like transcription factors REVEILLE4/LHY-CCA1-Like1 (RVE4/LCL1) and RVE8/LCL5 directly activate DREB1 expression under cold stress conditions. These RVEs function in the regulation of circadian clock-related gene expression under normal temperature conditions. They also activate the expression of HSF-independent heat-inducible genes under high-temperature conditions. Thus, there are thought to be specific regulatory mechanisms whereby the target genes of these transcription factors are switched when temperature changes are sensed. We revealed that NIGHT LIGHT-INDUCIBLE AND CLOCK-REGULATED (LNK) proteins act as coactivators of RVEs in cold and heat stress responses in addition to regulating circadian-regulated genes at normal temperatures. We found that among the four Arabidopsis LNKs, LNK1 and LNK2 function under normal and high-temperature conditions, and LNK3 and LNK4 function under cold conditions. Thus, these LNK proteins play important roles in inducing specific genes under different temperature conditions. Furthermore, LNK3 and LNK4 are specifically phosphorylated under cold conditions, suggesting that phosphorylation is involved in their activation.

Isoliquiritigenin inhibits virus replication and virus-mediated inflammation via NRF2 signaling

BackgroundThe transcription factor NRF2 is a master redox switch that regulates the cellular antioxidant response. However, recent advances have revealed new roles for NRF2, including the regulation of antiviral responses to various viruses, suggesting that pharmacological NRF2-activating agents may be a promising therapeutic drug for viral diseases. Isoliquiritigenin (ISL), a chalcone isolated from liquorice (Glycyrrhizae Radix) root, is reported to be a natural NRF2 agonist and has has antiviral activities against HCV (hepatitis C virus) and IAV (influenza A virus). However, the spectrum of antiviral activity and associated mechanism of ISL against other viruses are not well defined. PurposeThis study investigated the antiviral activity and underlying mechanism of ISL against vesicular stomatitis virus (VSV), influenza A virus (H1N1), encephalomyocarditis virus (EMCV), herpes simplex virus type 1 (HSV-1). MethodsWe evaluated the antiviral activity of ISL against VSV, H1N1, EMCV, and HSV-1 using flow cytometry and qRT-PCR analysis. RNA sequencing and bioinformatic analysis were performed to investigate the potential antiviral mechanism of ISL. NRF2 knockout cells were used to investigate whether NRF2 is required for the antiviral activity of ISL. The anti-apoptosis and anti-inflammatory activities of ISL were further measured by counting cell death ratio and assessing proinflammatory cytokines expression in virus-infected cells, respectively. In addition, we evaluated the antiviral effect of ISL in vivo by measuring the survival rate, body weights, histological analysis, viral load, and cytokine expression in VSV-infected mouse model. ResultsOur data demonstrated that ISL effectively suppressed VSV, H1N1, HSV-1, and EMCV replication in vitro. The antiviral activity of ISL could be partially impaired in NRF2-deficient cells. Virus-induced cell death and proinflammatory cytokines were repressed by ISL. Finally, we showed that ISL treatment protected mice against VSV infection by reducing viral titers and suppressing the expression of inflammatory cytokines in vivo. ConclusionThese findings suggest that ISL has antiviral and anti-inflammatory effects in virus infections, which are associated with its ability to activate NRF2 signaling, thus indicating that ISL has the potential to serve as an NRF2 agonist in the treatment of viral diseases.

Alternative splicing of the flip/flop cassette and TARP auxiliary subunits engage in a privileged relationship that fine-tunes AMPA receptor gating.

Alternative splicing of AMPA-type glutamate receptors (AMPARs) and allosteric modulation by auxiliary subunits, such as transmembrane AMPAR regulatory proteins (TARPs), are two important mechanisms that regulate the time course of glutamatergic neurotransmission. Prior work has shown that alternative splicing of the flip/flop cassette profoundly regulates TARP γ2 modulation, where flip receptor gating exhibits robust sensitivity to TARPs while flop isoforms are relatively insensitive to TARP modulation. Whether this splice variant-specific regulation extends to other auxiliary subunit families, such as cornichons (CNIHs), GSG1L, or CKAMPs, remains unknown. Here, we demonstrate that CNIH-3 modulation is unaffected by AMPAR alternative splicing due to inherent differences in how CNIH-3 and TARP γ2 modify channel gating. CNIH-3 slows receptor deactivation from the outset of current decay, consistent with structural evidence showing its point of contact at the level of the pore. In contrast, TARP γ2 acts through the KGK site of the ligand-binding domain (LBD) to slow the onset of desensitization. Although GSG1L and CKAMP44 primarily slow recovery from desensitization, their effects on channel gating are unaffected by alternative splicing, further underlining that structural events leading to the onset and recovery from desensitization are separable. Together, this work establishes that alternative splicing and TARP auxiliary subunits form a unique partnership that governs fast glutamatergic signaling at central synapses. Since proteomic studies suggest that all native AMPARs co-assemble with at least two TARPs, allosteric coupling between the flip/flop cassette and TARPs may represent a common design element in all AMPAR complexes of the mammalian brain.SIGNIFICANCE STATEMENT:All fast excitatory neurotransmission in the mammalian brain is mediated by AMPA-type glutamate receptors (AMPARs). The time course of AMPAR gating can be regulated by two distinct mechanisms: alternative splicing of the flip/flop cassette and association with auxiliary subunits. Although these regulatory mechanisms have been well studied individually, it is not clear whether alternative splicing impacts auxiliary protein modulation of AMPARs. Here, we compare the four main families of AMPAR auxiliary subunits, TARPs (γ2), Cornichons (CNIH-3), GSG1L and CKAMPs (CKAMP44), and find a privileged relationship between TARPs and the flip/flop cassette that is not shared by others. The flop cassette acts as a master switch to override TARP action, and this coupling represents a way to fine-tune AMPAR signaling.

A20 is a master switch of IL-33 signaling in macrophages and determines IL-33–induced lung immunity

IL-33 plays a major role in the pathogenesis of allergic diseases such as asthma and atopic dermatitis. On its release from lung epithelial cells, IL-33 primarily drives type 2 immune responses, accompanied by eosinophilia and robust production of IL-4, IL-5, and IL-13. However, several studies show that IL-33 can also drive a type 1 immune response. We sought to determine the role of A20 in the regulation of IL-33 signaling in macrophages and IL-33-induced lung immunity. We studied the immunologic response in lungs of IL-33-treated mice that specifically lack A20 in myeloid cells. We also analyzed IL-33 signaling in A20-deficient bone marrow-derived macrophages. IL-33-induced lung innate lymphoid cell type 2 expansion, type 2 cytokine production, and eosinophilia were drastically reduced in the absence of macrophage A20 expression, whereas neutrophils and interstitial macrophages in lungs were increased. Invitro, IL-33-mediated nuclear factor kappa B activation was only weakly affected in A20-deficient macrophages. However, in the absence of A20, IL-33 gained the ability to activate signal transducer and activator of transcription 1 (STAT1) signaling and STAT1-dependent gene expression. Surprisingly, A20-deficient macrophages produced IFN-γ in response to IL-33, which was fully STAT1-dependent. Furthermore, STAT1 deficiency partially restored the ability of IL-33 to induce ILC2 expansion and eosinophilia in myeloid cell-specific A20 knockout mice. We reveal a novel role for A20 as a negative regulator of IL-33-induced STAT1 signaling and IFN-γ production in macrophages, which determines lung immune responses.

Inter Dependence between Circadian Rhythm and Aging

Directly or indirectly light plays important physiological roles to regulate our body. It affects another master switch, the pineal gland, producer of melatonin- the sleep hormone. In addition to this hormone age is also big factor for regulating sleep. In this review we have put forth evidence for the relationship between the two important regulators for sleep.

Protective Effects of Sodium Para-Aminosalicylic Acid on Lead and Cadmium Co-Exposure in SH-SY5Y Cells.

Combined exposure to lead and cadmium is common in occupational environments. However, the effects of co-exposure to Pb-Cd on neurotoxicity have not been fully clarified. Sodium para-aminosalicylic acid (PAS-Na) has previously been shown to protect neurons from Pb-induced toxicity. This study aimed to investigate the beneficial effect of PAS-Na against co-exposure to Pb-Cd-induced neurodegeneration in SH-SY5Y cells. The MTT assay was used to detect the effects of Pb and Cd alone, or in combination, on SH-SY5Y cell survival. The effects of Pb and Cd alone or in combination on oxidative stress were assessed by reactive oxygen species (ROS) level. Nrf2, the master switch for antioxidant responses, was detected by immunofluorescence. Protein expression levels of PI3K, Akt, p-Akt, Nrf2 and HO-1 were determined by Western blot analysis. MTT assay results established that the survival rate of SH-SY5Y cells was not significantly affected by exposure to 1 μmol/L lead, 0.25 μmol/L cadmium, and 1-fold Pb-Cd mixture (1 μmol/L Pb + 0.25 μmol/L Cd), while 10-fold Pb-Cd combined exposure (10 μmol/L Pb + 2.5 μmol/L Cd) significantly reduced the survival rate of SH-SY5Y cells. Combined Pb-Cd exposure significantly increased intracellular ROS levels, and N-Acetyl-L-cysteine (NAC) treatment in the 10 μmol/L Pb + 2.5 μmol/L Cd group significantly decreased ROS expression levels, attenuating the levels of oxidative stress. Protein expression of PI3K and p-Akt significantly decreased in the 10 μmol/L Pb + 2.5 μmol/L Cd group, while the expression of PI3K and p-Akt protein increased after PAS-Na intervention. Immunofluorescence analysis showed that levels of Nrf2 in the nucleus increased in the 10 μmol/L Pb + 2.5 μmol/L Cd group, along with Nrf2 protein levels, suggesting that Nrf2 was translocated from the cytoplasm into the nucleus upon combined Pb-Cd exposure. In addition, HO-1 protein expression level, a downstream gene product of Nrf2, was increased. In response to NAC intervention, HO-1 protein expression levels significantly decreased. PAS-Na had the same intervention effect as NAC. Combined exposure to Pb-Cd induced oxidative stress and cytotoxicity in SH-SY5Y cells. PAS-Na displayed antagonistic effects on neurodegenerative changes induced by combined Pb-Cd exposure; hence, it may afford a novel treatment modality for exposure to these metals.

Insect diapause: from a rich history to an exciting future.

Diapause, a stage-specific developmental arrest, is widely exploited by insects to bridge unfavorable seasons. Considerable progress has been made in understanding the ecology, physiology and evolutionary implications of insect diapause, yet intriguing questions remain. A more complete understanding of diapause processes on Earth requires a better geographic spread of investigations, including more work in the tropics and at high latitudes. Questions surrounding energy management and trade-offs between diapause and non-diapause remain understudied. We know little about how maternal effects direct the diapause response, and regulators of prolonged diapause are also poorly understood. Numerous factors that were recently linked to diapause are still waiting to be placed in the regulatory network leading from photoreception to engagement of the diapause program. These factors include epigenetic processes and small noncoding RNAs, and emerging data also suggest a role for the microbiome in diapause regulation. Another intriguing feature of diapause is the complexity of the response, resulting in a diverse suite of responses that comprise the diapause syndrome. Select transcription factors likely serve as master switches turning on these diverse responses, but we are far from understanding the full complexity. The richness of species displaying diapause offers a platform for seeking common components of a 'diapause toolbox'. Across latitudes, during invasion events and in a changing climate, diapause offers grand opportunities to probe evolutionary change and speciation. At a practical level, diapause responses can be manipulated for insect control and long-term storage. Diapausing insects also contain a treasure trove of pharmacological compounds and offer promising models for human health.

MYC2: A Master Switch for Plant Physiological Processes and Specialized Metabolite Synthesis.

The jasmonic acid (JA) signaling pathway plays important roles in plant defenses, development, and the synthesis of specialized metabolites synthesis. Transcription factor MYC2 is a major regulator of the JA signaling pathway and is involved in the regulation of plant physiological processes and specialized metabolite synthesis. Based on our understanding of the mechanism underlying the regulation of specialized metabolite synthesis in plants by the transcription factor MYC2, the use of synthetic biology approaches to design MYC2-driven chassis cells for the synthesis of specialized metabolites with high medicinal value, such as paclitaxel, vincristine, and artemisinin, seems to be a promising strategy. In this review, the regulatory role of MYC2 in JA signal transduction of plants to biotic and abiotic stresses, plant growth, development and specialized metabolite synthesis is described in detail, which will provide valuable reference for the use of MYC2 molecular switches to regulate plant specialized metabolite biosynthesis.

GhWRKY41 forms a positive feedback regulation loop and increases cotton defence response against Verticillium dahliae by regulating phenylpropanoid metabolism.

Despite the established significance of WRKY proteins and phenylpropanoid metabolism in plant immunity, how WRKY proteins modulate aspects of the phenylpropanoid pathway remains undetermined. To understand better the role of WRKY proteins in plant defence, we identified a cotton (Gossypium hirsutum) protein, GhWRKY41, that is, universally and rapidly induced in three disease-resistant cotton cultivars following inoculation with the plant pathogenic fungus, Verticillium dahliae. We show that overexpression of GhWRKY41 in transgenic cotton and Arabidopsis enhances resistance to V. dahliae, while knock-down increases cotton more susceptibility to the fungus. GhWRKY41 physically interacts with itself and directly activates its own transcription. A genome-wide chromatin immunoprecipitation and high-throughput sequencing (ChIP-seq), in combination with RNA sequencing (RNA-seq) analyses, revealed that 43.1% of GhWRKY41-binding genes were up-regulated in cotton upon inoculation with V. dahliae, including several phenylpropanoid metabolism master switches, receptor kinases, and disease resistance-related proteins. We also show that GhWRKY41 homodimer directly activates the expression of GhC4H and Gh4CL, thereby modulating the accumulation of lignin and flavonoids. This finding expands our understanding of WRKY-WRKY protein interactions and provides important insights into the regulation of the phenylpropanoid pathway in plant immune responses by a WRKY protein.

P38 Mediates Tumor Suppression through Reduced Autophagy and Actin Cytoskeleton Changes in NRAS-Mutant Melanoma.

Hotspot mutations in the NRAS gene are causative genetic events associated with the development of melanoma. Currently, there are no FDA-approved drugs directly targeting NRAS mutations. Previously, we showed that p38 acts as a tumor suppressor in vitro and in vivo with respect to NRAS-mutant melanoma. We observed that because of p38 activation through treatment with the protein synthesis inhibitor, anisomycin leads to a transient upregulation of several targets of the cAMP pathway, representing a stressed cancer cell state that is often observed by therapeutic doses of MAPK inhibitors in melanoma patients. Meanwhile, genetically induced p38 or its stable transduction leads to a distinct cellular transcriptional state. Contrary to previous work showing an association of invasiveness with high p38 levels in BRAF-mutated melanoma, there was no correlation of p38 expression with NRAS-mutant melanoma invasion, highlighting the difference in BRAF and NRAS-driven melanomas. Although the role of p38 has been reported to be that of both tumor suppressor and oncogene, we show here that p38 specifically plays the role of a tumor suppressor in NRAS-mutant melanoma. Both the transient and stable activation of p38 elicits phosphorylation of mTOR, reported to be a master switch in regulating autophagy. Indeed, we observed a correlation between elevated levels of phosphorylated mTOR and a reduction in LC3 conversion (LCII/LCI), indicative of suppressed autophagy. Furthermore, a reduction in actin intensity in p38-high cells strongly suggests a role of mTOR in regulating actin and a remodeling in the NRAS-mutant melanoma cells. Therefore, p38 plays a tumor suppressive role in NRAS-mutant melanomas at least partially through the mechanism of mTOR upregulation, suppressed autophagy, and reduced actin polymerization. One or more combinations of MEK inhibitors with either anisomycin, rapamycin, chloroquine/bafilomycin, and cytochalasin modulate p38 activation, mTOR phosphorylation, autophagy, and actin polymerization, respectively, and they may provide an alternate route to targeting NRAS-mutant melanoma.

Protein Kinase C Modulation Determines the Mesoderm/Extraembryonic Fate Under BMP4 Induction From Human Pluripotent Stem Cells.

The interplay among mitogenic signaling pathways is crucial for proper embryogenesis. These pathways collaboratively act through intracellular master regulators to determine specific cell fates. Identifying the master regulators is critical to understanding embryogenesis and to developing new applications of pluripotent stem cells. In this report, we demonstrate protein kinase C (PKC) as an intrinsic master switch between embryonic and extraembryonic cell fates in the differentiation of human pluripotent stem cells (hPSCs). PKCs are essential to induce the extraembryonic lineage downstream of BMP4 and other mitogenic modulators. PKC-alpha (PKCα) suppresses BMP4-induced mesoderm differentiation, and PKC-delta (PKCδ) is required for trophoblast cell fate. PKC activation overrides mesoderm induction conditions and leads to extraembryonic fate. In contrast, PKC inhibition leads to β-catenin (CTNNB1) activation, switching cell fate from trophoblast to mesoderm lineages. This study establishes PKC as a signaling boundary directing the segregation of extraembryonic and embryonic lineages. The manipulation of intrinsic PKC activity could greatly enhance cell differentiation under mitogenic regulation in stem cell applications.

Analysis on the Ideal and Faith Education of College Counselors in the New Era

Ideal and faith is the "master switch", is the direction, strength and support. As the ideological and political work team of the Party, college counselors are the backbone of the student work in colleges and universities, and shoulder the important mission of "cultivating people by virtue". Firm ideals and beliefs play a very important role in the problems encountered on the growth of college students in the new era and the society in the future. Therefore, starting from the overall situation of the development of the party and the country, it is urgent to strengthen the ideal and faith education of college counselors and improve the overall quality of the counselors. This paper will analyze the current situation of the ideal faith education, explore the strategies and methods of the ideal faith education in the new era, so as to enhance the effectiveness of the ideal faith education of college counselors.