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Nature Communications Jun 2024JNK signaling is a critical regulator of inflammation and regeneration, but how it is controlled in specific tissue contexts remains unclear. Here we show that, in the...
JNK signaling is a critical regulator of inflammation and regeneration, but how it is controlled in specific tissue contexts remains unclear. Here we show that, in the Drosophila intestine, the TNF-type ligand, Eiger (Egr), is expressed exclusively by intestinal stem cells (ISCs) and enteroblasts (EBs), where it is induced by stress and during aging. Egr preferentially activates JNK signaling in a paracrine fashion in differentiated enterocytes (ECs) via its receptor, Grindelwald (Grnd). N-glycosylation genes (Alg3, Alg9) restrain this activation, and stress-induced downregulation of Alg3 and Alg9 correlates with JNK activation, suggesting a regulatory switch. JNK activity in ECs induces expression of the intermembrane protease Rhomboid (Rho), driving secretion of EGFR ligands Keren (Krn) and Spitz (Spi), which in turn activate EGFR signaling in progenitor cells (ISCs and EBs) to stimulate their growth and division, as well as to produce more Egr. This study uncovers an N-glycosylation-controlled, paracrine JNK-EGFR-JNK feedforward loop that sustains ISC proliferation during stress-induced gut regeneration.
Topics: Animals; Drosophila Proteins; ErbB Receptors; Intestines; MAP Kinase Signaling System; Drosophila melanogaster; Enterocytes; Stem Cells; Intestinal Mucosa; Drosophila; Glycosylation; Receptors, Invertebrate Peptide; Cell Proliferation; JNK Mitogen-Activated Protein Kinases; Signal Transduction; Cell Communication; Cell Differentiation; Epidermal Growth Factor; Membrane Proteins
PubMed: 38944657
DOI: 10.1038/s41467-024-49786-w -
Trends in Parasitology Jun 2024Gamete development is a precisely programmed process in Cryptosporidium parvum, a leading cause of diarrheal disease worldwide. Nava et al. recently described the...
Gamete development is a precisely programmed process in Cryptosporidium parvum, a leading cause of diarrheal disease worldwide. Nava et al. recently described the developmentally regulated expression of CDPK5 during male gametogenesis. Here we discuss their main findings, posing this protein kinase as a promising target for antiparasitic interventions.
PubMed: 38944561
DOI: 10.1016/j.pt.2024.06.007 -
Insect Biochemistry and Molecular... Jun 2024The larvae of the moth Hyalophora cecropia spin silk cocoons with morphologically distinct layers. We investigated the expression of the individual silk protein...
The larvae of the moth Hyalophora cecropia spin silk cocoons with morphologically distinct layers. We investigated the expression of the individual silk protein components of these cocoons in relation to the morphology of the silk gland and its affiliation to the different layers of the cocoon. The study used transcriptomic and proteomic analyses to identify 91 proteins associated with the silk cocoons, 63 of which have a signal peptide indicating their secretory nature. We checked the specificity of their expression in different parts of the SG and the presence of the corresponding protein products in each cocoon layer. Differences were observed among less abundant proteins with unclear functions. The representation of proteins in the inner envelope and intermediate space was similar, except for a higher proportion of probable contaminating proteins, mostly originating from the gut. On the other hand, the outer envelope contains a number of putative enzymes with unclear function. However, the protein most specific to the outer layer has sequence homology to putative serine/threonine kinase-like proteins and some adhesive proteins, and its closest homolog in Bombyx mori was found in the scaffold silk. This research provides valuable insights into the silk production of the cecropia moth, highlighting both similarities and differences to other moth species.
PubMed: 38944399
DOI: 10.1016/j.ibmb.2024.104152 -
Chemico-biological Interactions Jun 2024Dibutyl phthalate (DBP) is widely used in many consumer and personal care products. Here, we report vascular endothelial response to DBP in three different exposure...
Dibutyl phthalate (DBP) is widely used in many consumer and personal care products. Here, we report vascular endothelial response to DBP in three different exposure scenarios: after short-term exposure (24 h) of human endothelial cells (ECs) EA.hy926 to 10, 10, and 10 M DBP, long-term exposure (12 weeks) of EA.hy926 cells to 10, 10, and 10 M DBP, and exposure of rats (28 and 90 days) to 100, 500, and 5000 mg DBP/kg food. We examined different vascular functions such as migration of ECs, adhesion of ECs to the extracellular matrix, tube formation, the morphology of rat aorta, as well as several signaling pathways involved in controlling endothelial function. Short-term in vitro exposure to DBP increased migration of ECs through G protein-coupled estrogen receptor, extracellular signal-regulated kinase 1/2, and nitric oxide (NO) signaling and decreased adhesion to gelatin. Long-term in vitro exposure to DBP transiently increased EC migration and had a bidirectional effect on EC adhesion to gelatin and tube formation. These effects were accompanied by a sustained increase in NO production and endothelial NO synthase (eNOS) and Akt activity. In vivo, exposure to DBP for 90 days decreased the aortic wall-to-lumen ratio and increased eNOS and Akt phosphorylation in ECs of rat aorta. This comparative investigation has shown that exposure to DBP may affect vascular function by altering EC migration, adhesion to gelatin, and tube formation after short- and long-term in vitro exposure and by decreasing the aortic wall-to-lumen ratio in vivo. The eNOS-NO and Akt signaling could be important in mediating the effects of DBP in long-term exposure scenarios.
PubMed: 38944327
DOI: 10.1016/j.cbi.2024.111120 -
Antiviral Research Jun 2024Herpes simplex virus type 1 (HSV-1) is a neurotropic alphaherpesvirus that establishes a lifelong infection in sensory neurons of infected individuals, accompanied with...
Herpes simplex virus type 1 (HSV-1) is a neurotropic alphaherpesvirus that establishes a lifelong infection in sensory neurons of infected individuals, accompanied with intermittent reactivation of latent virus causing (a)symptomatic virus shedding. Whereas acyclovir (ACV) is a safe and highly effective antiviral to treat HSV-1 infections, long-term usage can lead to emergence of ACV resistant (ACV) HSV-1 and subsequently ACV refractory disease. Here, we isolated an HSV-1 strain from a patient with reactivated herpetic eye disease that did not respond to ACV treatment. The isolate carried a novel non-synonymous F289S mutation in the viral UL23 gene encoding the thymidine kinase (TK) protein. Because ACV needs conversion by viral TK and subsequently cellular kinases to inhibit HSV-1 replication, the UL23 gene is commonly mutated in ACV HSV-1 strains. The potential role of the F289S mutation causing ACV was investigated using CRISPR/Cas9-mediated HSV-1 genome editing. Reverting the F289S mutation in the original clinical isolate to the wild-type sequence S289F resulted in an ACV-sensitive (ACV) phenotype, and introduction of the F289S substitution in an ACV HSV-1 reference strain led to an ACV phenotype. In summary, we identified a new HSV-1 TK mutation in the eye of a patient with ACV refractory herpetic eye disease, which was identified as the causative ACV mutation with the aid of CRISPR/Cas9-mediated genome engineering technology. Direct editing of clinical HSV-1 isolates by CRISPR/Cas9 is a powerful strategy to assess whether single residue substitutions are causative to a clinical ACV phenotype.
PubMed: 38944159
DOI: 10.1016/j.antiviral.2024.105950 -
International Journal of Biological... Jun 2024Pleurotus ostreatus is one of the most cultivated edible fungi worldwide, but its lignocellulose utilization efficiency is relatively low (<50 %), which eventually...
Pleurotus ostreatus is one of the most cultivated edible fungi worldwide, but its lignocellulose utilization efficiency is relatively low (<50 %), which eventually affects the biological efficiency of P. ostreatus. Improving cellulase production and activity will contribute to enhancing the lignocellulose-degrading capacity of P. ostreatus. AMP-activated/Snf1 protein kinase plays important roles in regulating carbon and energy metabolism. The Snf1 homolog (PoSnf1) in P. ostreatus was obtained and analyzed using bioinformatics. The cellulose response of PoSnf1, the effect of the phosphorylation level of PoSnf1 on the expression of cellulose degradation-related genes, the putative proteins that interact with the phosphorylated PoSnf1 (P-PoSnf1), the cellobiose transport function of two sugar transporters (STP1 and STP2), and the interactions between PoSnf1 and STP1/STP2 were studied in this research. We found that cellulose treatment improved the phosphorylation level of PoSnf1, which further affected cellulase activity and the expression of most cellulose degradation-related genes. A total of 1, 024 proteins putatively interacting with P-PoSnf1 were identified, and they were enriched mainly in the substances transport and metabolism. Most of the putative cellulose degradation-related protein-coding genes could respond to cellulose. Among the P-PoSnf1-interacting proteins, the functions of two sugar transporters (STP1 and STP2) were further studied, and the results showed that both could transport cellobiose and were indirectly regulated by P-PoSnf1, and that STP2 could directly interact with PoSnf1. The results of this study indicated that PoSnf1 plays an important role in regulating the expression of cellulose degradation genes possibly by affecting cellobiose transport.
PubMed: 38944091
DOI: 10.1016/j.ijbiomac.2024.133503 -
Current Biology : CB Jun 2024By modulating stomatal opening and closure, plants control gas exchange, water loss, and photosynthesis in response to various environmental signals. During...
By modulating stomatal opening and closure, plants control gas exchange, water loss, and photosynthesis in response to various environmental signals. During light-induced stomatal opening, the transport of ions and solutes across the plasma membrane (PM) of the surrounding guard cells results in an increase in turgor pressure, leading to cell swelling. Simultaneously, vesicles for exocytosis are delivered via membrane trafficking to compensate for the enlarged cell surface area and maintain an appropriate ion-channel density in the PM. In eukaryotic cells, soluble N-ethylmaleimide-sensitive factor adaptor protein receptors (SNAREs) mediate membrane fusion between vesicles and target compartments by pairing the cognate glutamine (Q)- and arginine (R)-SNAREs to form a core SNARE complex. Syntaxin of plants 121 (SYP121) is a known Q-SNARE involved in stomatal movement, which not only facilitates the recycling of K channels to the PM but also binds to the channels to regulate their activity. In this study, we found that the expression of a receptor-like cytoplasmic kinase, low-K sensitive 4/schengen 1 (LKS4/SGN1), was induced by light; it directly interacted with SYP121 and phosphorylated T270 within the SNARE motif. Further investigation revealed that LKS4-dependent phosphorylation of SYP121 facilitated the interaction between SYP121 and R-SNARE vesicle-associated membrane protein 722 (VAMP722), promoting the assembly of the SNARE complex. Our findings demonstrate that the phosphorylation of SNARE proteins is an important strategy adopted by plants to regulate the SNARE complex assembly as well as membrane fusion. Additionally, we discovered the function of LKS4/SGN1 in light-induced stomatal opening via the phosphorylation of SYP121.
PubMed: 38944035
DOI: 10.1016/j.cub.2024.06.001 -
Journal of Pharmaceutical and... Jun 2024Oxylipins are important low abundant signaling molecules in living organisms. In platelets they play a primary role in platelet activation and aggregation in the course...
Non-enantioselective, enantioselective, and two-dimensional liquid chromatography coupled with tandem mass spectrometry for the study of stereochemical disposition of oxylipins in cGMP-regulated hemin-treated platelets.
Oxylipins are important low abundant signaling molecules in living organisms. In platelets they play a primary role in platelet activation and aggregation in the course of thrombotic events. In vivo, they are enzymatically synthesized by cyclooxygenases, lipoxygenases, or cytochrome P450 isoenzmes, resulting in diverse polyunsaturated fatty acid (FA) metabolites including hydroxy-, epoxy-, oxo-FAs, and endoperoxides with pro-thrombotic or anti-thrombotic effects. In a recent study, it was reported that hemin induces platelet death which was accompanied by enhanced reactive oxygen species (ROS) production (measured by flow cytometry) and lipid peroxidation (as determined by proxy using flow cytometry with BODIPY-C11 as sensor). Lipidomic studies further indicated significant changes of the platelet lipidome upon ex vivo hemin treatment, amongst others oxylipins were increased. The effect could be (at least partly) reversed by riociguat/diethylamine NONOate diethylammonium salt (DEA/NO) which modulates the soluble guanylate cyclase(sGC)-cGMP-cGMP-dependent protein kinase I(cGKI) signaling axis. In the original work, oxylipins were measured by a non-enantioselective UHPLC-tandem-MS assay which may not give the full picture whether oxylipin elevation is due to ROS or by enzymatic processes. We present here the study of the stereochemical disposition of hemin-induced platelet lipidome alterations using Chiralpak IA-U column with amylose tris(3,5-dimethylphenylcarbamate) chiral selector immobilized on 1.6 µm silica particles. It was found that the major platelet oxylipins 12-HETE, 12-HEPE and 14-HDoHE (from 12-LOX) and 12-HHT (from COX-1) were present in S-configuration indicating their enzymatic formation. On the other hand, both R and S enantiomers of 9- and 13-HODE, 11- and 15-HETE were detected, possibly due to enzyme promiscuity rather than non-specific oxidation (by ROS or autoxidation), as confirmed by multi-loop based two-dimensional LC-MS using selective comprehensive mode with achiral RPLC in the 1st dimension and chiral LC in the 2nd using a multiple heart-cutting interface. For 12-HETrE, a peak at the retention time of the R-enantiomer was ruled out as isobaric interference by 2D-LC-MS. In particular, arachidonic acid derivates 12(S)-HHT, 11(R)-HETE and 15(S)-HETE were found to be sensitive to hemin and cGMP modulation.
PubMed: 38943819
DOI: 10.1016/j.jpba.2024.116328 -
Virology Jun 2024Therapies targeting virus-host interactions are seen as promising strategies for treating gallid alphaherpesvirus 1 (ILTV) infection. Our study revealed a biphasic...
Therapies targeting virus-host interactions are seen as promising strategies for treating gallid alphaherpesvirus 1 (ILTV) infection. Our study revealed a biphasic activation of two MAPK cascade pathways, MEK/ERK and p38 MAPK, as a notably activated host molecular event in response to ILTV infection. It exhibits antiviral functions at different stages of infection. Initially, the MEK/ERK pathway is activated upon viral invasion, leading to a broad suppression of metabolic pathways crucial for ILTV replication, thereby inhibiting viral replication from the early stage of ILTV infection. As the viral replication progresses, the p38 MAPK pathway activates its downstream transcription factor, STAT1, further hindering viral replication. Interestingly, ILTV overcomes this biphasic antiviral barrier by hijacking host p38-AKT axis, which protects infected cells from the apoptosis induced by infection and establishes an intracellular equilibrium conducive to extensive ILTV replication. These insights could provide potential therapeutic targets for ILTV infection.
PubMed: 38943781
DOI: 10.1016/j.virol.2024.110159 -
Nutrition Research (New York, N.Y.) Jun 2024Canola meal, a by-product of processing canola into oil, reportedly contains high amounts of phenolic compounds and proteins. However, as canola meal is primarily used...
Canola meal, a by-product of processing canola into oil, reportedly contains high amounts of phenolic compounds and proteins. However, as canola meal is primarily used as feed for livestock, advances in multiple research fields are required to broaden its potential applications. Photoaging is caused by continuous exposure to ultraviolet (UV) radiation from sunlight. UV radiation generates reactive oxygen species and destroys collagen in the skin, thickening the epidermis, reducing elasticity, and causing wrinkles. We hypothesized that canola meal extract (CME) can mitigate the damage to skin associated with wrinkles induced by exposure to UVB radiation. To evaluate the anti-wrinkle effect, we administered CME orally to 40 female Hos:HR-1 hairless mice divided into 5 groups: (1) control mice, (2) a UVB group, and (3-5) CME-treated groups (CME-250, 500, and 1000 mg/kg body weight/day, respectively). All groups except the controls were irradiated with UVB 3 times a week to create wrinkles due to photoaging. CME administration inhibited the increase of the number, mean length, and mean depth of wrinkles induced by UVB radiation as assessed using a skin replica. Histopathological image analysis revealed that CME administration resulted in a decrease in epidermal thickness and an increase in collagen content, while increasing catalase activity and hydroxyproline content in skin tissues. CME administration inhibited the phosphorylation of mitogen-activated protein kinase and decreased the production of collagenase and gelatinase. These results suggest that CME, an upcycled material, has the potential to develop into a healthful and functional food ingredient with anti-wrinkling effects.
PubMed: 38943729
DOI: 10.1016/j.nutres.2024.06.002