A rice amino acid transporter OsMP1 acts as a quantitative trait locus against blast fungus and leaf-blight bacterium.

Amino acid homeostasis is interconnected with the immune network of plants. During plant-pathogen interaction, amino acid transporters (AATs) have been shown to be involved in plant immune responses. However, the molecular mechanism by which how AATs function in this process remains elusive. In this study, we identify OsMP1 that acts as a quantitative trait locus against blast fungus from a joint analysis of GWAS and QTL mapping in rice. Heterogeneous expression of OsMP1 in yeast supports its function in transporting a wide range of amino acids, including Thr, Ser, Phe, His and Glu. OsMP1 could also mediate 15N-Glu efflux and influx in Xenopus oocyte cells. The expression of OsMP1 is dramatically induced by Magnaporthe oryzae in the resistant landrace Heikezijing, while remaining unresponsive in the susceptible landrace Suyunuo. Overexpressing OsMP1 in Suyunuo enhances disease resistance to blast fungus and leaf-blight bacterium without yield penalty. Furthermore, the overexpression of OsMP1 leads to increased accumulation of Thr, Ser, Phe and His in the leaves. And the heightened levels of these amino acids contribute to reduced disease susceptibility, which is associated with upregulated jasmonic acid pathway. Thus, our results elucidate the pivotal role of OsMP1 in disease resistance and provide a potential target for breeding more resistant rice cultivars without compromising yield.

A handy way for forming N-doped TiO2/carbon from pectin and d,l-serine hydrazide hydrochloride.

N-doped TiO2/carbon composites (N-TiPC) have shown excellent photodegradation performances to the organic contaminants but are limited by the multistage preparation (i.e., preparation of porous carbon, preparation of N-doped TiO2, and loading of N-doped TiO2 on porous carbon). Here, we develop a handy way by combining the Pickering emulsion-gel template route and chelation reaction of polysaccharides. The N-TiPC is obtained by calcinating pectin/Dl-serine hydrazide hydrochloride (SHH)-Ti4+ chelate and is further described by modern characterization techniques. The results show that the N atom is successfully doped into the TiO2 lattice, and the bandgap value of N-TiPC is reduced to 2.3 eV. Moreover, the particle size of N-TiPC remains about 10 nm. The configurations of the composites are simulated using DFT calculation. The photocatalytic experiments show that N-TiPC has a high removal efficiency for methylene blue (MB) and oxytetracycline hydrochloride (OTC-HCL). The removal ratios of MB (20 mg/L, 50 mL) and OTC-HCL (30 mg/L, 50 mL) are 99.41 % and 78.29 %, respectively. The cyclic experiments show that the photocatalyst has good stability. Overall, this study provides a handy way to form N-TiPC with enhanced photodegradation performances. It can also be promoted to other macromolecules such as cellulose and its derivatives, sodium alginate, chitosan, lignin, etc.

Aldehyde group pendant-grafted pectin-based injectable hydrogel.

Periodate oxidation has been the widely accepted route for obtaining aldehyde group-functionalized polysaccharides but significantly influenced the various physicochemical properties due to the ring opening of the backbone of polysaccharides. The present study, for the first time, presents a novel method for the preparation of aldehyde group-functionalized polysaccharides that could retain the ring structure and the consequent rigidity of the backbone. Pectin was collected as the representative of polysaccharides and modified with cyclopropyl formaldehyde to obtain pectin aldehyde (AP), which was further crosslinked by DL-lysine (LYS) via the Schiff base reaction to prepare injectable hydrogel. The feasibility of the functionalization was proved by FT-IR and 1H NMR techniques. The obtained hydrogel showed acceptable mechanical properties, self-healing ability, syringeability, and sustained-release performance. Also, as-prepared injectable hydrogel presented great biocompatibility with a cell proliferation rate of 96 %, and the drug-loaded hydrogel exhibited clear inhibition of cancer cell proliferation. Overall, the present study showed a new method for the preparation of aldehyde group-functionalized polysaccharides, and the drug-loaded hydrogel has potential in drug release applications.

Polymerization strategy for cellulose nanocrystals-based photonic crystal films with water resisting property.

Cellulose nanocrystals (CNCs) can form a liquid crystal film with a chiral nematic structure by evaporative-induced self-assembly (EISA). It has attracted much attention as a new class of photonic liquid crystal material because of its intrinsic, unique structural characteristics, and excellent optical properties. However, the CNCs-based photonic crystal films are generally prepared via the physical crosslinking strategy, which present water sensitivity. Here, we developed CNCs-g-PAM photonic crystal film by combining free radical polymerization and EISA. FT-IR, SEM, POM, XRD, TG-DTG, and UV-Vis techniques were employed to characterize the physicochemical properties and microstructure of the as-prepared films. The CNCs-g-PAM films showed a better thermo-stability than CNCs-based film. Also, the mechanical properties were significantly improved, viz., the elongation at break was 9.4 %, and tensile strength reached 18.5 Mpa, which was a much better enhancement than CNCs-based film. More importantly, the CNCs-g-PAM films can resist water dissolution for more than 24 h, which was impossible for the CNCs-based film. The present study provided a promising strategy to prepare CNCs-based photonic crystal film with high flexibility, water resistance, and optical properties for applications such as decoration, light management, and anti-counterfeiting.

Genome-Wide Association Study Identifies Rice Panicle Blast-Resistant Gene Pb4 Encoding a Wall-Associated Kinase.

Rice blast is one of the most devastating diseases, causing a significant reduction in global rice production. Developing and utilizing resistant varieties has proven to be the most efficient and cost-effective approach to control blasts. However, due to environmental pressure and intense pathogenic selection, resistance has rapidly broken down, and more durable resistance genes are being discovered. In this paper, a novel wall-associated kinase (WAK) gene, Pb4, which confers resistance to rice blast, was identified through a genome-wide association study (GWAS) utilizing 249 rice accessions. Pb4 comprises an N-terminal signal peptide, extracellular GUB domain, EGF domain, EGF-Ca2+ domain, and intracellular Ser/Thr protein kinase domain. The extracellular domain (GUB domain, EGF domain, and EGF-Ca2+ domain) of Pb4 can interact with the extracellular domain of CEBiP. Additionally, its expression is induced by chitin and polygalacturonic acid. Furthermore, transgenic plants overexpressing Pb4 enhance resistance to rice blast. In summary, this study identified a novel rice blast-resistant gene, Pb4, and provides a theoretical basis for understanding the role of WAKs in mediating rice resistance against rice blast disease.

Ti4+-dopamine/sodium alginate multicomponent complex derived N-doped TiO2@carbon nanocomposites for efficient removal of methylene blue.

A one-pot route for the preparation of TiO2@carbon nanocomposite from Ti4+/polysaccharide coordination complex has been developed and shown advantages in operation, cost, environment, etc. However, the photodegradation rate of methylene blue (MB) needs to be improved. N-doping has been proven as an efficient means to enhance photodegradation performance. Thus, the present study upgraded the TiO2@carbon nanocomposite to N-doped TiO2@carbon nanocomposite (N-TiO2@C) from Ti4+-dopamine/sodium alginate multicomponent complex. The composites were characterized by FT-IR, XRD, XPS, UV-vis DRS, TG-DTA, and SEM-EDS. The obtained TiO2 was a typical rutile phase, and the carboxyl groups existed on N-TiO2@C. The photocatalyst consequently showed high removal efficiency of MB. The cycling experiment additionally indicated the high stability of N-TiO2@C. The present work provided a novel route for preparing N-TiO2@C. Moreover, it can be extended to prepare N-doped polyvalent metal oxides@carbon composites from all water-soluble polysaccharides such as cellulose derivatives, starch, and guar gum.

Genome-Wide Association Study Identifies a Rice Panicle Blast Resistance Gene Pb3 Encoding NLR Protein.

Rice blast is a worldwide fungal disease that seriously affects the yield and quality of rice. Identification of resistance genes against rice blast disease is one of the effective ways to control this disease. However, panicle blast resistance genes, which are useful in the fields, have rarely been studied due to the difficulty in phenotypic identification and the environmental influences. Here, panicle blast resistance-3 (Pb3) was identified by a genome-wide association study (GWAS) based on the panicle blast resistance phenotypes of 230 Rice Diversity Panel I (RDP-I) accessions with 700,000 single-nucleotide polymorphism (SNP) markers. A total of 16 panicle blast resistance loci (PBRLs) within three years including one repeated locus PBRL3 located in chromosome 11 were identified. In addition, 7 genes in PBRL3 were identified as candidate genes by haplotype analysis, which showed significant differences between resistant and susceptible varieties. Among them, one nucleotide-binding domain and Leucine-rich Repeat (NLR) gene Pb3 was highly conserved in multiple resistant rice cultivars, and its expression was significantly induced after rice blast inoculation. Evolutionary analysis showed that Pb3 was a typical disease resistance gene containing coiled-coil, NB-ARC, and LRR domains. T-DNA insertion mutants and CRISPR lines of Pb3 showed significantly reduced panicle blast resistance. These results indicate that Pb3 is a panicle blast resistance gene and GWAS is a rapid method for identifying panicle blast resistance in rice.

Luteolin-7-O-rutinoside from Pteris cretica L. var. nervosa attenuates LPS/D-gal-induced acute liver injury by inhibiting PI3K/AKT/AMPK/NF-κB signaling pathway.

Pteris cretica L. var. nervosa is one of the most well-known Chinese medicines. Although it is widely used to treat jaundice hepatitis, the main ingredient for its treatment was not thoroughly explored until recently. Essentially, the purpose of this study is to find the monomer compound in Pteris cretica L. var. nervosa, which is most likely to be effective in treating liver injury. Through the model of LPS/D-gal-induced liver injury in mice, the best therapeutic site of the total extract was explored, the chemical components of the parts with the best therapeutic effect were separated, a total of 10 flavonoids were isolated, and the RAW264.7 cells induced by LPS were used as the experimental model to explore the preliminary anti-inflammatory activity of NO production in vitro. Finally, the anti-inflammatory activity and the highest content in this plant Luteolin-7-O-rutinoside (LUT) were selected, as the object of study in vivo. It was found that LUT could not only reduce alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, but also significantly reduce the release of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß), and inhibit PI3K/AKT/AMPK/NF-κB pathway. In addition, LUT can increase levels of SOD and GSH to reduce oxidative stress. It has an obvious therapeutic effect on acute liver injury induced by LPS/D-gal in mice. Therefore, infer LUT is a functional substance in Pteris cretica L. var. nervosa.

Genome-Wide Association Study Identifies a Rice Panicle Blast Resistance Gene, Pb2, Encoding NLR Protein.

Rice blast is one of the main diseases in rice and can occur in different rice growth stages. Due to the complicated procedure of panicle blast identification and instability of panicle blast infection influenced by the environment, most cloned rice resistance genes are associated with leaf blast. In this study, a rice panicle blast resistance gene, Pb2, was identified by genome-wide association mapping based on the panicle blast resistance phenotypes of 230 Rice Diversity Panel 1 (RDP1) accessions with 700,000 single-nucleotide polymorphism (SNP) markers. A genome-wide association study identified 18 panicle blast resistance loci (PBRL) within two years, including 9 reported loci and 2 repeated loci (PBRL2 and PBRL13, PBRL10 and PBRL18). Among them, the repeated locus (PBRL10 and PBRL18) was located in chromosome 11. By haplotype and expression analysis, one of the Nucleotide-binding domain and Leucine-rich Repeat (NLR) Pb2 genes was highly conserved in multiple resistant rice cultivars, and its expression was significantly upregulated after rice blast infection. Pb2 encodes a typical NBS-LRR protein with NB-ARC domain and LRR domain. Compared with wild type plants, the transgenic rice of Pb2 showed enhanced resistance to panicle and leaf blast with reduced lesion number. Subcellular localization of Pb2 showed that it is located on plasma membrane, and GUS tissue-staining observation found that Pb2 is highly expressed in grains, leaf tips and stem nodes. The Pb2 transgenic plants showed no difference in agronomic traits with wild type plants. It indicated that Pb2 could be useful for breeding of rice blast resistance.

Bruceine H Mediates EGFR-TKI Drug Persistence in NSCLC by Notch3-Dependent ß-Catenin Activating FOXO3a Signaling.

Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) protein serve as a critical pillar in the treatment of non-small cell lung cancer (NSCLC), but resistance is universal. Identifying the potential key factors of drug resistance to EGFR-TKIs is essential to treat patients with EGFR mutant lung cancer. Our research here shows that bruceine H suppressed the proliferation, migration, and invasion of lung cancer cells; inhibited the growth of human NSCLC cell xenografts; and enhanced the therapeutic effects of gefitinib in the PC-9/GR xenograft models, possibly by inhibiting Notch3. In order to analyze the potential targets of the combination of Notch3 and EGFR-TKIs on resistance to EGFR, we analyzed the differences of gene expression between NSCLC tissues and EGFR-driven gefitinib-resistant tumoral groups and then identify through the WGCNA key genes that may provide therapeutic targets for TKI-resistant lung cancer xenograft models. We confirmed that EGFR-TKI in combination with Notch3 inhibitor can inhibit the expression of ß-catenin and enhance the level of FOXO3a, leading to improved recurrence-free survival and overall survival of the xenotransplantation model. These results support that the combination of gefitinib and bruceine H may provide a promising alternative strategy for treating acquired EGFR-TKI resistance in patients with NSCLC.

Quassinoids from Brucea javanica and attenuates lipopolysaccharide-induced acute lung injury by inhibiting PI3K/Akt/NF-κB pathways.

Four new quassinoids (1-4) and twenty known analogues (5-24) were isolated from the seeds of Brucea javanica. All the compounds belong to tetracyclic quassinoids. The structures of the new compounds were elucidated by comprehensive spectroscopic analysis, including HRESIMS and 1D, 2D NMR. In in vitro bioassays, (5-9, 17-19 and 23) showed inhibitory activities for nitric oxide (NO) release in LPS-activated MH-S macrophages and IC50 values of 0.11-45.56 µM. Among them, bruceoside B significantly decreased LPS-induced NO, secretion of inflammatory factor cytokines tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß). Western Blot was used to verify the expression of p-IκB-α, IκB-α, p-NF-κB, NF-κB, Bax, Bcl-2, Caspase-3, p-PI3K, PI3K, p-Akt, and Akt proteins in PI3K/Akt/NF-κB signal pathway. Bruceoside B inhibited the activity of Akt and its downstream pathways and reduced the activation of apoptotic. In vivo, it was found that bruceoside B had obvious therapeutic effect on LPS-induced acute lung injury (ALI) in mice, and the effect of tissue section was obvious. The regulatory signal pathway of bruceoside B on inflammation was consistent with the anti-inflammatory pathway in vitro. Therefore, the results implied that bruceoside B has a certain therapeutic effect on inflammation and has a certainly effect on acute lung injury.

[Interaction of DNAJB13 with HK1 in mouse].

OBJECTIVE: To investigate the presence of interactions between DNAJB13 and HK1. METHODS: The open reading frame of Dnajb13 gene was amplified from mouse testis cDNA by PCR. The PCR products were then inserted into pGEX-4T-1 vector after double digestion and identified by sequencing. The recombinant plasmids were transformated into competent DH5a cells, and the fusion protein was expressed with IPTG induction. SDS-PAGE Coomassie brilliant blue staining and Western blot analysis were used to detect the fusion protein expression. The protein precipitated by GST-DNAJB13 in GST pull down assay was detected by Western blotting. RESULTS: The recombinant plasmid pGEX-4T-1-Dnajb13 was successfully constructed and verified. E.coli transformed with the recombinant plasmid expressed abundant fusion protein. GST pull down assay showed interactions between DNAJB13 and HK1. CONCLUSION: DNAJB13 interacts with HK1 in mouse testis and probably participates in spermatogenesis and the regulation of sperm motility.