The Calcium-Dependent Protein Kinase TaCDPK7 Positively Regulates Wheat Resistance to Puccinia striiformis f. sp. tritici.

Ca2+ plays a crucial role as a secondary messenger in plant development and response to abiotic/biotic stressors. Calcium-dependent protein kinases (CDPKs/CPKs) are essential Ca2+ sensors that can convert Ca2+ signals into downstream phosphorylation signals. However, there is limited research on the function of CDPKs in the context of wheat-Puccinia striiformis f. sp. tritici (Pst) interaction. In this study, we aimed to address this gap by identifying putative CDPK genes from the wheat reference genome and organizing them into four phylogenetic clusters (I-IV). To investigate the expression patterns of the TaCDPK family during the wheat-Pst interaction, we analyzed time series RNA-seq data and further validated the results through qRT-PCR assays. Among the TaCDPK genes, TaCDPK7 exhibited a significant induction during the wheat-Pst interaction, suggesting that it has a potential role in wheat resistance to Pst. To gain further insights into the function of TaCDPK7, we employed virus-induced gene silencing (VIGS) to knock down its expression which resulted in impaired wheat resistance to Pst, accompanied by decreased accumulation of hydrogen peroxide (H2O2), increased fungal biomass ratio, reduced expression of defense-related genes, and enhanced pathogen hyphal growth. These findings collectively suggest that TaCDPK7 plays an important role in wheat resistance to Pst. In summary, this study expands our understanding of wheat CDPKs and provides novel insights into their involvement in the wheat-Pst interaction.

Curing Behavior of UV-Initiated Surface-Modified Nano-TiO2/Epoxy Resin Prepolymers and the Properties of Cured Composites.

Nano-titanium dioxides (nano-TiO2) surface modified with isopropyl tri(dioctylpyrophosphate) titanate (NDZ-201), a titanate coupling agent, and 3-glycidoxypropyltrimethoxysilane (KH-560), a silane coupling agent, were separately mixed with bisphenol A epoxy resin (DEGBA) prepolymer and then cured using a UV-normal temperature synergistic curing process. Then, the isothermal curing process of the system was investigated by differential scanning calorimetry (DSC). The relationship between the organization structures, mechanical properties, and heat resistance properties of the cured composites and material formulation was studied, and the DSC results showed that the addition of nano-TiO2 reduced the curing reaction rate constant k1 and increased the k2 of the prepolymer, while the activation energy of the curing reaction after UV irradiation Ea1 decreased, and the activation energy in the middle and later periods Ea2 increased. The characterization results of the composite material showed that nano-TiO2 as a scattering agent reduced the photoinitiation efficiency of UV light, and due to its obvious agglomeration tendency in the epoxy resin, the mechanical properties of the composite material were poor. The dispersibility of the coupling-agent-modified nano-TiO2 in the epoxy resin was greatly enhanced, and the mechanical and heat resistance properties of the composite material improved remarkably. The comparison results of the two coupling agents showed that NDZ-201 had better performance in increasing the impact strength by 6.8% (minimum value, the same below) and the maximum thermal decomposition rate temperature by 4.88 °C of the composite, while KH-560 improved the tensile strength by 7.3% and the glass transition temperature (Tg) by 3.34 °C of the composite.

Protection against Hypoxia-Reoxygenation Injury of Hippocampal Neurons by H2S via Promoting Phosphorylation of ROCK2 at Tyr722 in Rat Model.

The RhoA-ROCK signaling pathway is associated with the protective effects of hydrogen sulfide (H2S) against cerebral ischemia. H2S protects rat hippocampal neurons (RHNs) against hypoxia-reoxygenation (H/R) injury by promoting phosphorylation of RhoA at Ser188. However, effect of H2S on the phosphorylation of ROCK2-related sites is unclear. The present study was designed to investigate whether H2S can play a role in the phosphorylation of ROCK2 at Tyr722, and explore whether this role mediates the protective effect of H/R injury in RHNs. Prokaryotic recombinant plasmids ROCK2wild-pGEX-6P-1 and ROCK2Y722F-pGEX-6P-1 were constructed and transfected into E. coli in vitro, and the expressed protein, GST-ROCK2wild and GST-ROCK2Y722F were used for phosphorylation assay in vitro. Eukaryotic recombinant plasmids ROCK2Y722-pEGFP-N1 and ROCK2Y722F-pEGFP-N1 as well as empty plasmid were transfected into the RHNs. Western blot assay and whole-cell patch-clamp technique were used to detect phosphorylation of ROCK2 at Tyr722 and BKCa channel current in the RHNs, respectively. Cell viability, leakages of intracellular enzymes lactate dehydrogenase (LDH), and nerve-specific enolase (NSE) were measured. The H/R injury was indicated by decrease of cell viability and leakages of intracellular LDH and NSE. The results of Western blot have shown that NaHS, a H2S donor, significantly promoted phosphorylation of GST-ROCK2wild at Tyr722, while no phosphorylation of GST-ROCK2Y722F was detected. The phosphorylation of ROCK2wild promoted by NaHS was also observed in RHNs. NaHS induced more potent effects on protection against H/R injury, phosphorylation of ROCK2 at Tyr722, inhibition of ROCK2 activity, as well as increase of the BKCa current in the ROCK2Y722-pEGFP-N1-transfected RHNs. Our results revealed that H2S protects the RHNs from H/R injury through promoting phosphorylation of ROCK2 at Tyr722 to inhibit ROCK2 activity and potentially by opening channel currents.

Association between IKBKAP polymorphisms and Hirschsprung's disease susceptibility in Chinese children.

Background: Hirschsprung's disease (HSCR) is a rare congenital disease in which enteric nervous system (ENS) in the distal intestine is absent. HSCR is a disease involving genetic factors and environmental factors. Despite a series of genes have been revealed to contribute to HSCR, many HSCR associated genes were yet not identified. Previous studies had identified that a potential susceptibility gene of HSCR was an inhibitor of kappa light polypeptide gene enhancer in B-cells, kinase complex-associated protein (IKBKAP). The study aimed to explore the association of genetic variants in IKBKAP and HSCR susceptibility in southern Chinese children. Methods: Single nucleotide polymorphism (SNPs) were genotyped by the Mass ARRAY iPLEX Gold system (Sequenom, San Diego, CA, USA) on all samples, which included 1,470 HSCR children (cases) and 1,473 healthy children (controls). The associations between SNPs and HSCR or clinical subtypes were assessed by comparing their allele frequencies in corresponding case and control samples. Different genetic models, including additive, recessive, and dominant models, were tested using PLINK 1.9 software. Results: Further subgroup analysis revealed rs2275630 as a total colonic aganglionosis (TCA)-specific susceptibility locus. The present study is the first to indicate that IKBKAP rs2275630 were associated with HSCR susceptibility, especially in TCA patients. Conclusions: We conclude that IKBKAP rs2275630 is a susceptibility gene of HSCR.

Roles of the RhoA-ROCK Signaling Pathway in the Endothelial H2S Production and Vasodilation in Rat Cerebral Arteries.

Cerebral endothelial H2S protects against cerebral ischemia-reperfusion injury through vasodilation, but its cerebral vasodilation mechanism and regulation of production are poorly understood. The RhoA-ROCK pathway plays important roles in vascular function. In this study, the roles of this pathway in the endothelial H2S production and vasodilation in rat cerebral arteries were investigated. Acetylcholine significantly increased H2S-generating enzyme cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST) protein expressions and H2S production in rat cerebrovascular endothelial cells (ECs), but the increases were markedly decreased by the M receptor blocker atropine or the CSE inhibitor dl-propargylglycine. Pretreatment with dl-propargylglycine or the 3-MST inhibitor l-aspartic acid markedly reduced the acetylcholine-increased H2S; CSE protein expression and H2S levels in the ECs were obviously attenuated by the RhoA agonist U46619 but increased by the RhoA inhibitor C3 transferase. U46619 also reduced 3-MST protein expression; Acetylcholine markedly inhibited RhoA protein expression and activity, but the inhibition was obviously reversed by atropine, dl-propargylglycine, and l-aspartic acid, respectively; Acetylcholine-induced endothelium-dependent vasodilation in rat cerebral basilar artery was significantly attenuated by pretreatment with dl-propargylglycine or l-aspartic acid or RhoA inhibitor CCG-1423 or ROCK inhibitor KD025, and was further decreased by co-pretreatment with dl-propargylglycine (or l-aspartic acid) and CCG-1423 (or KD025); NaHS significantly relaxed rat cerebral basilar artery vascular smooth muscle cells and inhibited ROCK1/2 activities, phosphorylated myosin light chain (MLC) protein expression, and KCl-increased [Ca2+]i, but these relaxation and inhibitions were markedly attenuated by pretreatment with C3 transferase or ROCK inhibitor Y27632. Our results demonstrated that endothelial H2S production is promoted by activation of the M receptor but inhibited by the RhoA-ROCK pathway in rat cerebral arteries; the endothelial H2S induces cerebral vasodilation by inhibiting this pathway to reduce phosphorylation of MLC and [Ca2+]i in vascular smooth muscle cells.

Rutin Inhibits the Progression of Osteoarthritis Through CBS-Mediated RhoA/ROCK Signaling.

Osteoarthritis (OA) is a chronic joint disease characterized by the deterioration of cartilage and subchondral bone in the joints. Currently, there is no complete cure for OA, only treatments designed to temporarily relieve pain and improve function. Compared with the high cost of surgical treatment, medical treatment of OA is more acceptable and cost-effective. Rutin, as a flavonoid, has been shown to have anti-OA properties. We evaluated the effects of rutin on chondrocytes in lipopolysaccharide (LPS)-induced OA and on OA in rats induced by anterior cruciate ligament transection. We found that rutin effectively reduced the expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and matrix metalloproteinase 13 (MMP-13) and increased the expression of Col II and aggrecan (p < 0.001). In addition, we also found that rutin increased the expression of cystathionine-ß-synthase (CBS) and inhibited the expression of Rho-related coiled-coil protein kinase (ROCK) in chondrocytes (p < 0.05), thereby effectively inhibiting the inflammatory progression of OA. We concluded that rutin inhibits the inflammatory progression of OA through the CBS-mediated RhoA/ROCK signaling pathway.

Genome-wide hypermethylation is closely associated with abnormal expression of genes involved in neural development in induced pluripotent stem cells derived from a Down syndrome mouse model.

Mental retardation is the main clinical manifestation of Down syndrome (DS), and neural abnormalities occur during the early embryonic period and continue throughout life. Tc1, a model mouse for DS, carries the majority part of the human chromosome 21 and has multiple neuropathy phenotypes similar to patients with DS. To explore the mechanism of early neural abnormalities of Tc1 mouse, induced pluripotent stem (iPS) cells from Tc1 mice were obtained, and genome-wide gene expression and methylation analysis were performed for Tc1 and wild-type iPS cells. Our results showed hypermethylation profiles for Tc1 iPS cells, and the abnormal genes were shown to be related to neurodevelopment and distributed on multiple chromosomes. In addition, important genes involved in neurogenesis and neurodevelopment were shown to be downregulated in Tc1 iPS cells. In short, our study indicated that genome-wide hypermethylation leads to the disordered expression of genes associated with neurodevelopment in Tc1 mice during early development. Overall, our work provided a useful reference for the study of the molecular mechanism of nervous system abnormalities in DS.

Bonded Repair Optimization of Cracked Aluminum Alloy Plate by Microwave Cured Carbon-Aramid Fiber/Epoxy Sandwich Composite Patch.

Fiber-reinforced epoxy sandwich composites, which were designed as the bonded repair patches to better recover the mechanical performance of a central cracked aluminum alloy plate, were layered by carbon and aramid fiber layers jointly and cured by microwave method in this study. The static tensile and bending properties of both carbon-aramid fiber/epoxy sandwich composite patches and the cracked aluminum alloy plates after bonded repair were systematically investigated. By comparing the mechanical performance with traditional single carbon-fiber-reinforced composite patches, it can be found that the bending performance of carbon-aramid fiber sandwich composite patches was effectively improved after incorporation of flexible aramid fiber layers into the carbon fiber layers, but the tensile strength of sandwich composite patches was weakened to some extent. Especially, the sandwich patches with 3 fiber layers exhibited better tensile and bending performance in comparison to patches of 5 and 7 fiber layers. The optimized 3-layer carbon-aramid fiber sandwich patch repaired plate recovered 86% and 190% of the tensile and bending performance in comparison to the uncracked ones, respectively, showing a considerable repair majorization effect for the cracked aluminum alloy plate.