Regulation Of Signaling Research Articles

The alternative polyadenylation regulator CFIm25 promotes macrophage differentiation and activates the NF-κβ pathway.

Macrophages are required for our body's development and tissue repair and protect against microbial attacks. We previously reported a crucial role for regulation of mRNA 3'-end cleavage and polyadenylation (C/P) in monocyte to macrophage differentiation. The CFIm25 subunit of the C/P complex showed a striking increase upon differentiation of monocytes with Phorbol Myristate Acetate, suggesting that it promotes this process. To test this hypothesis, CFIm25 was overexpressed in two different monocytic cell lines, followed by differentiation. Both cell lines showed a significant increase in macrophage characteristics and an earlier slowing of the cell cycle. In contrast, depletion of CFIm25 hindered differentiation. Cell cycle slowing upon CFIm25 overexpression was consistent with a greater decrease in the proliferation markers PCNA and cyclin D1, coupled with increased 3'UTR lengthening of cyclin D1 mRNA. Since choice of other poly(A) sites could be affected by manipulating CFIm25, we identified additional genes with altered use of poly(A) sites during differentiation and examined how this changed upon CFIm25 overexpression. The mRNAs of positive regulators of NF-κB signaling, TAB2 and TBL1XR1, and NFKB1, which encodes the NF-κB p50 precursor, underwent 3'UTR shortening that was associated with increased protein expression compared to the control. Cells overexpressing CFIm25 also showed elevated levels of phosphorylated NF-κB-p65 and the NF-κB targets p21, Bcl-XL, ICAM1 and TNF-α at an earlier time and greater resistance to NF-κB chemical inhibition. In conclusion, our study supports a model in which CFIm25 accelerates the monocyte to macrophage transition by promoting alternative polyadenylation events which lead to activation of the NF-κB pathway.

Experimental evolution of Saccharomyces cerevisiae for caffeine tolerance alters multidrug resistance and target of rapamycin signaling pathways.

Caffeine is a natural compound that inhibits the major cellular signaling regulator target of rapamycin (TOR), leading to widespread effects including growth inhibition. Saccharomyces cerevisiae yeast can adapt to tolerate high concentrations of caffeine in coffee and cacao fermentations and in experimental systems. While many factors affecting caffeine tolerance and TOR signaling have been identified, further characterization of their interactions and regulation remain to be studied. We used experimental evolution of S. cerevisiae to study the genetic contributions to caffeine tolerance in yeast, through a collaboration between high school students evolving yeast populations coupled with further research exploration in university labs. We identified multiple evolved yeast populations with mutations in PDR1 and PDR5, which contribute to multidrug resistance, and showed that gain-of-function mutations in multidrug resistance family transcription factors Pdr1, Pdr3, and Yrr1 differentially contribute to caffeine tolerance. We also identified loss-of-function mutations in TOR effectors Sit4, Sky1, and Tip41 and showed that these mutations contribute to caffeine tolerance. These findings support the importance of both the multidrug resistance family and TOR signaling in caffeine tolerance and can inform future exploration of networks affected by caffeine and other TOR inhibitors in model systems and industrial applications.

Exploring causal effects and potential mediating mechanisms of genetically linked environmental senses with intracerebral hemorrhage.

The occurrence mechanism of intracerebral hemorrhage remains unclear. Several recent studies have highlighted the close relationship between environmental senses and intracerebral hemorrhage, but the mechanisms of causal mediation are inconclusive. We aimed to investigate the causal relationships and potential mechanisms between environmental senses and intracerebral hemorrhage. Multiple Mendelian randomization methods were used to identify a causal relationship between environmental senses and intracerebral hemorrhage. Gut microbiota and brain imaging phenotypes were used to find possible mediators. Enrichment and molecular interaction analyses were used to identify potential mediators and molecular targets. No causal relationship between temperature and visual perception with intracerebral hemorrhage was found, whereas long-term noise was identified as a risk factor for intracerebral hemorrhage (OR 2.95, 95% CI: 1.25 to 6.93, PIVW = 0.01). The gut microbiota belonging to the class Negativicutes and the order Selenomonadales and the brain image-derived phenotypes ICA100 node 54, edge 803, edge 1149, and edge 1323 played mediating roles. "Regulation of signaling and function in synaptic organization" is the primary biological pathway of noise-induced intracerebral hemorrhage, and ARHGAP22 may be the critical gene. This study emphasized the importance of environmental noise in the prevention, disease management, and underlying biological mechanisms of intracerebral hemorrhage.

Endogenous cell membrane interactome mapping for the GLP-1 receptor in different cell types.

The GLP-1 receptor, one of the most successful drug targets for the treatment of type 2 diabetes and obesity, is known to engage multiple intracellular signaling proteins. However, it remains less explored how the receptor interacts with proteins on the cell membrane. Here, we present a ligand-based proximity labeling approach to interrogate the native cell membrane interactome for the GLP-1 receptor after agonist simulation. Our study identified several unreported putative cell membrane interactors for the endogenous receptor in either a pancreatic β cell line or a neuronal cell line. We further uncovered new regulators of GLP-1 receptor-mediated signaling and insulinotropic responses in β cells. Additionally, we obtained a time-resolved cell membrane interactome map for the receptor in β cells. Therefore, our study provides a new approach that is generalizable to map endogenous cell membrane interactomes for G-protein-coupled receptors to decipher the molecular basis of their cell-type-specific functional regulation.

Molecular mechanism of IKK catalytic dimer docking to NF-κB substrates

The inhibitor of κB (IκB) kinase (IKK) is a central regulator of NF-κB signaling. All IKK complexes contain hetero- or homodimers of the catalytic IKKβ and/or IKKα subunits. Here, we identify a YDDΦxΦ motif, which is conserved in substrates of canonical (IκBα, IκBβ) and alternative (p100) NF-κB pathways, and which mediates docking to catalytic IKK dimers. We demonstrate a quantitative correlation between docking affinity and IKK activity related to IκBα phosphorylation/degradation. Furthermore, we show that phosphorylation of the motif’s conserved tyrosine, an event previously reported to promote IκBα accumulation and inhibition of NF-κB gene expression, suppresses the docking interaction. Results from integrated structural analyzes indicate that the motif binds to a groove at the IKK dimer interface. Consistently, suppression of IKK dimerization also abolishes IκBα substrate binding. Finally, we show that an optimized bivalent motif peptide inhibits NF-κB signaling. This work unveils a function for IKKα/β dimerization in substrate motif recognition.

REGULATION OF RETINOGENESIS IN PRENATAL ONTOGENESIS AND ITS DISRUPTION IN AGE-RELATED MACULAR DEGENERATION

One of the main causes of blindness in the elderly in developed countries is age-related macular degeneration (AMD) [1, 2, 3]. Active research is being conducted to identify putative molecular targets for the development of an effective strategy for conservative treatment of both atrophic and neovascular forms of this disease [4, 5, 6], but at the present stage, pharmacotherapy is effective only for some patients, and is insufficient to stop the progression of the disease or eliminate the damage that has already occurred. The most promising and promising potential treatment options are considered to be the introduction of cellular technologies with retinal cell replacement and targeted pharmacotherapy. The aim of this study was to investigate the role of the retinal development inducer, SIRT1 [7, 8, 9], in retinogenesis to justify pharmacological inhibition of this protein as a possible treatment option for neovascular AMD. Using immunohistochemistry and immunocytochemistry, we assessed the expression and subcellular localization of SIRT1 and its innate inhibitor DBC1 in the retina of fetuses, adults, and mice. We also studied SIRT1 in retinal progenitor cells derived from mice and humans, the former having been used in small interfering RNA studies. SIRT1 is widely expressed in the developing and adult retina and is a regulator of key genes in retinal development, namely PAX6, Nestin, and CRX [10, 11, 12]. Moreover, we found that photoreceptor progenitor cells were among the smallest cells in a heterogeneous mouse retinal progenitor cell population [13, 14, 15]. Collectively, these results provide a basis for manipulating SIRT1 expression in small retinal progenitors as a means to increase the yield of photoreceptors for transplantation in retinal degeneration models [16, 17]. Furthermore, SIRT1 was found to be highly expressed in human-derived choroidal neovascular membranes, allowing its activity to be pharmacologically inhibited by the drug nicotinamide as a potent regulator of angiogenic and hypoxic signaling in a human retinal pigment epithelial cell line at both the protein level using angiogenesis arrays and at the RNA level using whole genome microarrays [18, 19]. These results point to the SIRT1 inhibitor, Nicotinamide, as a possible agent for treatment of neovascular AMD. Further studies of Nicotinamide are warranted in animal models of AMD. To the best of our knowledge, this is the first time that a detailed analysis of SIRT1 as a regulator of both retinal development and choroidal neovascularization has been reported.

Beauvericin Reverses Epithelial-to-Mesenchymal Transition in Triple-Negative Breast Cancer Cells through Regulation of Notch Signaling and Autophagy.

Metastasis stands as a prime contributor to triple-negative breast cancer (TNBC) associated mortality worldwide, presenting heightened severity and significant challenges due to limited treatment options. Addressing TNBC metastasis necessitates innovative approaches and novel therapeutics to specifically target its propensity for dissemination to distant organs. Targeted therapies capable of reversing epithelial-to-mesenchymal transition (EMT) play a crucial role in suppressing metastasis and enhancing the treatment response. Beauvericin, a promising fungal secondary metabolite, exhibits significant potential in diminishing the viability of EMT-induced TNBC cells by triggering intracellular oxidative stress, as evidenced by an enhanced reactive oxygen species level and reduced mitochondrial transmembrane potential. In monolayer cultures, it has exhibited an IC50 of 2.3 μM in both MDA-MB-468 and MDA-MB-231 cells, while in 3D spheroids, the IC50 values are 9.7 and 7.1 μM, respectively. Beauvericin has also reduced the migratory capability of MDA-MB-468 and MDA-MB-231 cells by 1.5- and 1.7-fold, respectively. Both qRT-PCR and Western blot analysis have shown significant upregulation in the expression of epithelial marker (E-cadherin) and downregulation in the expression of mesenchymal markers (N-cadherin, vimentin, Snail, Slug, and β-catenin), following treatment, indicating reversal of EMT. Furthermore, beauvericin has suppressed the Notch signaling pathway by substantially downregulating Notch-1, Notch-3, Hes-1, and cyclinD3 expression and induced autophagy as observed by elevated expression of autophagy markers LC3 and Beclin-1. In conclusion, beauvericin has successfully downregulated TNBC cell survival by inducing oxidative stress and suppressed their migratory potential by reversing EMT through the inhibition of Notch signaling and activation of autophagy.

A computational analysis revealed BES1 transcription factor and β-amylase as crosstalk elements in Upland cotton species (Gossypium sp.)

Cotton is a resilient and multipurpose crop, meeting major of the world’s textile needs while also yielding byproducts like edible oil and animal feed. Starch plays a crucial role in cotton fabric production. It enhances fabric strength by forming a protective film around cotton fibers, making them more resistant to wear and tear. BES1 (brassinosteroid insensitive 1) is a key regulator in brassinosteroid signaling. It controls thousands of target genes involved in development processes. Interestingly, two β-amylase proteins (BAM7 and BAM8) are part of the BES1 family, despite their primary function as β-amylases. β-Amylase (BAM) and BES1 are two gene families with functional and regulatory roles in controlling shoot growth and development by mediating brassinosteroid effects. They share similar domains and participate in various biological processes, tolerance and responses to stresses like salt and drought. In a computational analysis comparing Arabidopsis and Gossypium species, BAM and BES1 were characterized. BES1 genes were grouped into four clusters based on the comparison of the two species. Two clusters corresponded to BAM7 and BAM8, while the other two clusters were associated with BES1. The conserved nucleotide domain sequence is GCTGGATGG. Short tandem repeats include TG and TTG, which can serve as molecular markers. BES1 is specifically linked to cellulose and fiber production and holds promise as a candidate for plant selection and breeding in Gossypium (cotton).

Involvement of the Wnt/β-catenin signalling pathway in heterotopic ossification and ossification-related diseases.

Heterotopic ossification (HO) is a pathological condition characterized by the formation of bone within soft tissues. The development of HO is a result of abnormal activation of the bone formation programs, where multiple signalling pathways, including Wnt/β-catenin, BMP and hedgehog signalling, are involved. The Wnt/β-catenin signalling pathway, a conserved pathway essential for various fundamental activities, has been found to play a significant role in pathological bone formation processes. It regulates angiogenesis, chondrocyte hypertrophy and osteoblast differentiation during the development of HO. More importantly, the crosstalk between Wnt signalling and other factors including BMP, Hedgehog signalling, YAP may contribute in a HO-favourable manner. Moreover, several miRNAs may also be involved in HO formation via the regulation of Wnt signalling. This review aims to summarize the role of Wnt/β-catenin signalling in the pathogenesis of HO, its interactions with related molecules, and potential preventive and therapeutic measures targeting Wnt/β-catenin signalling.

NOSTRIN is involved in benign prostatic hyperplasia via inhibition of proliferation, oxidative stress, and inflammation in prostate epithelial cells.

Benign prostatic hyperplasia (BPH) is a common disease among older men characterized by non-malignant proliferation of epithelial cells and inflammation. Nitric oxide synthase traffic inducer (NOSTRIN) is a pleiotropic regulator of endothelial cell function and signaling and exerts anti-inflammatory, anti-proliferation, and modulating nuclear factor-kappa B (NF-κB) signaling effects. Its expression and function in BPH tissues and prostate epithelial cells are unknown. The study aims to investigate the expression and functions of NOSTRIN in BPH, and its possible molecular mechanism. The BPH model was constructed in male Institute of Cancer Research (ICR) mice using 5 mg/kg/day testosterone propionate (TP) for 30 days, and the model was evaluated by detecting prostate index, prostate epithelial thickness, and prostate-specific antigen (PSA) expression. Dihydrotestosterone (DHT, 10 nM)-induced in vitro model of human prostate epithelial cells (RWPE-1) was established. We generated lentivirus-harboring human NOSTRIN. The mRNA expression was detected by real-time quantitative polymerase chain reaction (PCR) assay; the protein expression or localization was detected by western blot assay, immunohistochemistry, or immunofluorescence staining. Cell proliferation was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 5-ethynyl-2'-deoxyuridine (EdU) staining. Reactive oxygen species (ROS) production was observed by dihydroethidium staining. Nitric oxide (NO) and malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were detected using commercial kits. Enzyme-linked immunosorbent assay (ELISA) was used to determine levels of interleukin 1 beta (IL1B), interleukin 6 (IL6), interferon gamma (IFNG), and tumor necrosis factor (TNF). NOSTRIN expression was significantly inhibited in the TP-induced ICR mouse BPH model and DHT-induced model of RWPE-1 proliferation. Protein expression of the BPH-related and proliferation markers PSA and proliferating cell nuclear antigen (PCNA) was suppressed in NOSTRIN-overexpressing RWPE-1 cells exposed to DHT. NOSTRIN overexpression notably inhibited the RWPE-1 cell proliferation in vitro, as evidenced by MTT and EdU staining. NOSTRIN overexpression significantly decreased the expression of cell cycle-related proteins cyclin dependent kinase 4 (CDK4) and cyclin D1 (CCND1) in vitro. The production of ROS, NO, and lipid peroxidation products MDA was inhibited by NOSTRIN overexpression in vitro, while the SOD activity was increased. NOSTRIN overexpression reduced the mRNA expression of inflammatory mediator nitric oxide synthase 2 (NOS2) and inhibited the mRNA expression and secretion of pro-inflammatory cytokines IL1B, IL6, IFNG, and TNF in vitro. The mechanistic studies revealed an increased phosphorylation of NF-κB p65 in vivo and in vitro. Remarkably, NOSTRIN overexpression notably inhibited the protein expression of phospho-NF-κB p65 in vitro. NOSTRIN is involved in BPH by inhibiting proliferation, oxidative stress, and inflammation in prostate epithelial cells. These functions may act through the inhibition of NF-κB signaling.

Pax2a, Pax5 and Cdh1-β-catenin, but not Wnt, protect sensory hair cells from destabilizing effects of fgf signaling on cell adhesion

During inner ear development, specification of sensory epithelia requires dynamic regulation of Fgf signaling. In zebrafish, high levels of Fgf are necessary and sufficient to specify the utricular/vestibular macula, whereas the saccular/auditory macula requires a discreet lower level of Fgf. Transcription factors Pax2a and Pax5 act downstream of Fgf to help specify utricular identity, loss of which leads to sporadic extrusion of hair cells from the utricular macula. The mechanism for utricular instability is not clear but is potentially related to reduced expression of cdh1/Ecad caused by disruption of pax2a. Here we find that utricular hair cells in pax2−/− and pax5−/− mutants gradually lose adhesive contact with the macula, leading to ejection of intact hair cells from either the basal or apical surface. The phenotype is far more severe in pax2a−/− mutants and is progressive, resulting in loss of large swaths of the utricular hair cells by 82 hpf. Instability is caused by elevated Fgf signaling in the utricle, as modest reduction of Fgf signaling with a low dose of SU5402 prevents hair cell loss in pax2a−/− mutants. Misexpression of cdh1/Ecad in pax2a−/− mutants partially rescues pax2a−/− mutants. Elevating β-catenin levels by treatment with BIO, or misexpression of a mutant form of β-catenin lacking transcriptional activity but retaining cell adhesion function, fully rescues pax2a−/− mutants. In contrast, Wnt signaling is not required for utricular stability. Thus, Pax2/5 factors serve to counteract the destabilizing effects of elevated Fgf signaling needed to specify utricular identity.

Targeting protein condensation in cGAS-STING signaling pathway.

The cGAS-STING signaling pathway plays a pivotal role in sensing cytosolic DNA and initiating innate immune responses against various threats, with disruptions in this pathway being associated with numerous immune-related disorders. Therefore, precise regulation of the cGAS-STING signaling is crucial to ensure appropriate immune responses. Recent research, including ours, underscores the importance of protein condensation in driving the activation and maintenance of innate immune signaling within the cGAS-STING pathway. Consequently, targeting condensation processes in this pathway presents a promising approach for modulating the cGAS-STING signaling and potentially managing associated disorders. In this review, we provide an overview of recent studies elucidating the role and regulatory mechanism of protein condensation in the cGAS-STING signaling pathway while emphasizing its pathological implications. Additionally, we explore the potential of understanding and manipulating condensation dynamics to develop novel strategies for mitigating cGAS-STING-related disorders in the future.

Resolving and functional analysis of RNA editing sites in sheep ovaries and associations with litter size

Sheep litter size is a critical trait in mutton production. While litter size regulation in relation to DNA transcription have been rigorously investigated, the function of RNA editing remains less explored. To elucidate the mechanisms controlling sheep fecundity at the RNA editing level and identify pivotal RNA editing sites, this study scrutinised RNA editing sites (RESs) in follicular and luteal phases of ovaries from sheep with high and low fecundity, and the functions of population-specific RESs were subsequently analysed. A total of 2 182 475 RESs, 74.61% of which were A-to-I and C-to-U sites, were identified. These RESs were fairly evenly dispersed over the chromosomes, with 46.8% showing close clustering (inter-site distance < 300 bp). Notably, 93% were primarily situated in intronic and intergenic regions. In the follicular phase, pivotal RESs were found in the introns of genes including LPS responsive beige-like anchor, MCC regulator of Wnt signalling, and RWD domain containing 3, among others, and in the exon region of EvC ciliary complex subunit 2. In the luteal phase, RESs were observed in the introns of genes such as H/ACA ribonucleoprotein assembly factor and SDA1 domain-containing 1, and the exon and 3′UTR regions of polypeptide N-acetylgalactosaminyltransferase 15 and ilvB acetolactate synthase-like, respectively. High-fecundity sheep showed RESs in the follicular phase in genes such as fibrillin 1, cyclin−dependent kinase 6, and roundabout 1, and in genes such as autophagy−related 2B and versican in the luteal phase. Thirteen RESs specific to the follicular phase and eight specific to the luteal phase were identified in high-fecundity sheep ovaries. These RESs offer promising molecular targets and enhance understanding of multiple births in sheep from the perspective of posttranscriptional alterations.

Cell type-specific and subcellular expression of phospholipid phosphatase-related proteins to modulate lyso-phosphatidic acid synaptic signaling in the developing and adult CNS.

Lysophosphatidic acid (LPA) is a bioactive phospholipid that participates in critical processes in neural development and adult brain function and is implicated in various pathophysiological conditions. Along with its six well-characterized receptors, atypical regulators of LPA signaling have also been suggested, including phospholipid phosphatase-related proteins (PLPPRs). PLPPRs have been mostly studied in the developing brain where they control LPA-dependent axon guidance, cortical network hyperexcitability, and glutamatergic neurotransmission. PLPPR4 and PLPPR3 represent two closely related proteins reported to localize predominantly in dendrites and axons, respectively, and differ in their developmental expression patterns. Herein, we have revised the expression patterns of PLPPRs in the cerebellum, dorsal and ventral hippocampus, prefrontal cortex (PFC), nucleus accumbens, and striatum during development and in the adult using quantitative PCR. Expression patterns of Plppr2,4 and 5 were consistent with previous studies, whereas Plppr3 and Plppr1 exhibited a unique expression profile in nucleus accumbens (NAc) and striatum in later developmental and adult stages, which we verified at the protein level for PLPPR3. To investigate neuron type-specific expression at the single cell level, we developed a bioinformatic tool to analyze recent single-cell RNA-sequencing data in the cerebral cortex and hippocampus of adult mice. Our analysis revealed a widespread but also selective adult neuron-type expression with higher expression levels of Plppr3, Plppr1, and Plppr5 in GABAergic and Plppr4 and Plppr2 in glutamatergic neurons. PLPPR4 has been identified as a post-synaptic modulator of LPA levels in glutamatergic synapses operating via an uptake mechanism, to control LPA-dependent cortical network hyperexcitability. Using subcellular fractionation experiments, we found that both PLPPR4 and PLPPR3 are co-expressed in adult synaptosomal membranes. Furthermore, flow cytometry experiments in HEK293 cells showed comparable LPA uptake by PLPPR4 and PLPPR3, whereas PLPRR3, but not PLPPR4, induced also uptake of monoacylglycerol, the dephosphorylation product of LPA. We propose that synaptic LPA may be subject to both pre-synaptic and post-synaptic mechanisms of regulation by PLPPRs in addition to LPARs in developing and adult synapses.

Specific 3-O-sulfated heparan sulfate domains regulate salivary gland basement membrane metabolism and epithelial differentiation

Heparan sulfate (HS) regulation of FGFR function, which is essential for salivary gland (SG) development, is determined by the immense structural diversity of sulfated HS domains. 3-O-sulfotransferases generate highly 3-O-sulfated HS domains (3-O-HS), and Hs3st3a1 and Hs3st3b1 are enriched in myoepithelial cells (MECs) that produce basement membrane (BM) and are a growth factor signaling hub. Hs3st3a1;Hs3st3b1 double-knockout (DKO) mice generated to investigate 3-O-HS regulation of MEC function and growth factor signaling show loss of specific highly 3-O-HS and increased FGF/FGFR complex binding to HS. During development, this increases FGFR-, BM- and MEC-related gene expression, while in adult, it reduces MECs, increases BM and disrupts acinar polarity, resulting in salivary hypofunction. Defined 3-O-HS added to FGFR pulldown assays and primary organ cultures modulates FGFR signaling to regulate MEC BM synthesis, which is critical for secretory unit homeostasis and acinar function. Understanding how sulfated HS regulates development will inform the use of HS mimetics in organ regeneration.

Temporal regulation of BMP2 growth factor signaling in response to mechanical loading is linked to cytoskeletal and focal adhesion remodeling

Biophysical cues have the ability to enhance cellular signaling response to Bone Morphogenetic Proteins, an essential growth factor during bone development and regeneration. Yet, therapeutic application of Bone Morphogenetic Protein 2 (BMP2) is restricted due to uncontrolled side effects. An understanding of the temporal characteristics of mechanically regulated signaling events and underlying mechanism is lacking. Using a 3D bioreactor system in combination with a soft macroporous biomaterial substrate, we mimic the in vivo environment that BMP2 is acting in. We show that the intensity and duration of BMP2 signaling increases with increasing loading frequency in synchrony with the number and size of focal adhesions. Long-term mechanical stimulation increases the expression of BMP receptor type 1B, specific integrin subtypes and integrin clustering. Together, this triggered a short-lived mechanical echo that enhanced BMP2 signaling even when BMP2 is administered directly after mechanical stimulation, but not when it is applied after a resting period of ≥30 min. Interfering with cytoskeletal remodeling hinders focal adhesion remodeling verifying its critical role in shifting cells into a state of high BMP2 responsiveness. The design of biomaterials that exploit this potential locally at the site of injury will help to overcome current limitations of clinical growth factor treatment.

Comparative transcriptome and coexpression network analysis revealed the regulatory mechanism of Astragalus cicer L. in response to salt stress

BackgroundAstragalus cicer L. is a perennial rhizomatous legume forage known for its quality, high biomass yield, and strong tolerance to saline-alkaline soils. Soil salinization is a widespread environmental pressure. To use A. cicer L. more scientifically and environmentally in agriculture and ecosystems, it is highly important to study the molecular response mechanism of A. cicer L. to salt stress.ResultsIn this study, we used RNA-seq technology and weighted gene coexpression network analysis (WGCNA) were performed. The results showed 4 key modules were closely related to the physiological response of A. cicer. L. to salt stress. The differentially expressed genes (DEGs) of key modules were mapped into the KEGG database, and found that the most abundant pathways were the plant hormone signal transduction pathway and carbon metabolism pathway. The potential regulatory networks of the cytokinin signal transduction pathway, the ethylene signal transduction pathway, and carbon metabolism related pathways were constructed according to the expression pathways of the DEGs. Seven hub genes in the key modules were selected and distributed among these pathways. They may involved in the positive regulation of cytokinin signaling and carbon metabolism in plant leaves, but limited the positive expression of ethylene signaling. Thus endowing the plant with salt tolerance in the early stage of salt stress.ConclusionsBased on the phenotypic and physiological responses of A. cicer L. to salt stress, this study constructed the gene coexpression network of potential regulation to salt stress in key modules, which provided a new reference for exploring the response mechanism of legumes to abiotic stress.

A Butyrate-Yielding Dietary Supplement Prevents Acute Alcoholic Liver Injury by Modulating Nrf2-Mediated Hepatic Oxidative Stress and Gut Microbiota.

Alcoholic liver disease (ALD) is a globally prevalent form of liver disease for which there is no effective treatment. Recent studies have found that a significant decrease in butyrate was closely associated with ALD development. Given the low compliance and delivery efficiency associated with oral-route butyrate administration, a highly effective butyrate-yielding dietary supplement, butyrylated high-amylose maize starch (HAMSB), is a good alternative approach. Here, we synthesized HAMSB, evaluated the effect of HAMSB on acute ALD in mice, compared its effect with that of oral administration of butyrate, and further studied the potential mechanism of action. The results showed HAMSB alleviated acute ALD in mice, as evidenced by the inhibition of hepatic-function impairment and the improvement in liver steatosis and lipid metabolism; in these respects, HAMSB supplementation was superior to oral sodium butyrate administration. These improvements can be attributed to the reduction of oxidative stress though the regulation of Nrf2-mediated antioxidant signaling in the liver and the improvement in the composition and function of microbiota in the intestine. In conclusion, HAMSB is a safe and effective dietary supplement for preventing acute ALD that could be useful as a disease-modifying functional food or candidate medicine.

MOF-mediated PRDX1 acetylation regulates inflammatory macrophage activation

Signaling-dependent changes in protein phosphorylation are critical to enable coordination of transcription and metabolism during macrophage activation. However, the role of acetylation in signal transduction during macrophage activation remains obscure. Here, we identify the redox signaling regulator peroxiredoxin 1 (PRDX1) as a substrate of the lysine acetyltransferase MOF. MOF acetylates PRDX1 at lysine 197, preventing hyperoxidation and thus maintaining its activity under stress. PRDX1 K197ac responds to inflammatory signals, decreasing rapidly in mouse macrophages stimulated with bacterial lipopolysaccharides (LPSs) but not with interleukin (IL)-4 or IL-10. The LPS-induced decrease of PRDX1 K197ac elevates cellular hydrogen peroxide accumulation and augments ERK1/2, but not p38 or AKT, phosphorylation. Concomitantly, diminished PRDX1 K197ac stimulates glycolysis, potentiates H3 serine 28 phosphorylation, and ultimately enhances the production of pro-inflammatory mediators such as IL-6. Our work reveals a regulatory role for redox protein acetylation in signal transduction and coordinating metabolic and transcriptional programs during inflammatory macrophage activation.

Extracellular vesicles are involved in the paracrine communication between epithelial cells in different regions of the domestic cat epididymis.

Sperm maturation depends on exposure to specific microenvironments within the different segments of the epididymis, but mechanisms underlying how these microenvironments are produced or maintained are not well understood. We hypothesized that epididymal extracellular vesicles (EVs) could play a role in the process of maintaining microenvironments in different regions of the epididymis. Specifically, we tested whether the EVs from different regions of the epididymis can serve as a form of paracrine communication between cells in different segments. Domestic cat tissues were used to develop a reproducible in vitro culture system for corpus epididymis explants that were then exposed to EVs collected from upstream (i.e. caput) segments. The impacts of different culture or exposure conditions were compared by analyzing the morphology, apoptosis, transcriptional activity, and gene expression in the explants. Here, we report the development of the first in vitro culture system for epididymal tissue explants in the domestic cat model. Using this system, we found that EVs from the caput segment have a significant effect on the transcriptional profile of tissue from the corpus segment (1233 differentially expressed genes due to EV supplementation). Of note, expression of genes associated with regulation of epithelial cell differentiation and cytokine signaling in the epididymis were regulated by the presence of EVs. Together, our findings comprise the first report of paracrine control of segmental gene regulation by epididymal EVs in any species. These results contribute to a better understanding of epididymis biology and could lead to techniques to enhance or suppress male fertility.