A high rain-erosion resistant bio-based nanogel with continuous immunity induction for plant virus inhibition.

Tobacco mosaic virus (TMV) is the most widely spread and harmful virus in the world, causing serious economic losses annually. However, the low anti-erosion ability of the pesticides for TMV management make it easy to be washed by the rain, which makes the effective duration of the pesticides shorter. In this paper, a new bio-based nanogel with superior antiviral activity was reported, and its slow-release behavior, rain erosion resistance and the antiviral mechanism was systematically studied. The results determined that the nanogels (Zn2+@ALGNP and Zn2+@ALGNP@PL) exhibited sustained releasing of Zn2+ with a 7 days duration, and the ε-PL coating could enhance the releasing rate of Zn2+. Moreover, Zn2+@ALGNP@PL displayed a lower contact angle, indicating greater adhesion to the leaf surface, and in consequence imposed better resistance to simulate rain erosion than pure Zn2+. Strikingly, Zn2+@ALGNP@PL could inhibit plant virus infection by aggregating the virions and reducing its coat protein stability, as well as inducing the efficient expression of reactive oxygen species, antioxidant enzymes and resistance genes to enhance plant resistance and promote plant growth. Overall, this study had successfully developed a high rain-erosion resistant bio-based nanogel capable of continue to induce resistant plants and promote plant growth.

A chitosan-coated lentinan-loaded calcium alginate hydrogel induces broad-spectrum resistance to plant viruses by activating Nicotiana benthamiana calmodulin-like (CML) protein 3.

Control of plant virus diseases largely depends on the induced plant defence achieved by the external application of synthetic chemical inducers with the ability to modify defence-signalling pathways. However, most of the molecular mechanisms underlying these chemical inducers remain unknown. Here, we developed a chitosan-coated lentinan-loaded hydrogel and discovered how it protects plants from different virus infections. The hydrogel was synthesized by coating chitosan on the surface of the calcium alginate-lentinan (LNT) hydrogel (SL-gel) to form a CSL-gel. CSL-gels exhibit the capacity to prolong the stable release of lentinan and promote Ca2+ release. Application of CSL-gels on the root of plants induces broad-spectrum resistance against plant viruses (TMV, TRV, PVX and TuMV). RNA-seq analysis identified that Nicotiana benthamiana calmodulin-like protein gene 3 (NbCML3) is upregulated by the sustained release of Ca2+ from the CSL-gel, and silencing and overexpression of NbCML alter the susceptibility and resistance of tobacco to TMV. Our findings provide evidence that this novel and synthetic CSL-gel strongly inhibits the infection of plant viruses by the sustainable release of LNT and Ca2+ . This study uncovers a novel mode of action by which CSL-gels trigger NbCML3 expression through the stable and sustained release of Ca2+ .

Transcriptome and functional analysis revealed the intervention of brassinosteroid in regulation of cold induced early flowering in tobacco.

Cold environmental conditions may often lead to the early flowering of plants, and the mechanism by cold-induced flowering remains poorly understood. Microscopy analysis in this study demonstrated that cold conditioning led to early flower bud differentiation in two tobacco strains and an Agilent Tobacco Gene Expression microarray was adapted for transcriptomic analysis on the stem tips of cold treated tobacco to gain insight into the molecular process underlying flowering in tobacco. The transcriptomic analysis showed that cold treatment of two flue-cured tobacco varieties (Xingyan 1 and YunYan 85) yielded 4176 and 5773 genes that were differentially expressed, respectively, with 2623 being commonly detected. Functional distribution revealed that the differentially expressed genes (DEGs) were mainly enriched in protein metabolism, RNA, stress, transport, and secondary metabolism. Genes involved in secondary metabolism, cell wall, and redox were nearly all up-regulated in response to the cold conditioning. Further analysis demonstrated that the central genes related to brassinosteroid biosynthetic pathway, circadian system, and flowering pathway were significantly enhanced in the cold treated tobacco. Phytochemical measurement and qRT-PCR revealed an increased accumulation of brassinolide and a decreased expression of the flowering locus c gene. Furthermore, we found that overexpression of NtBRI1 could induce early flowering in tobacco under normal condition. And low-temperature-induced early flowering in NtBRI1 overexpression plants were similar to that of normal condition. Consistently, low-temperature-induced early flowering is partially suppressed in NtBRI1 mutant. Together, the results suggest that cold could induce early flowering of tobacco by activating brassinosteroid signaling.

MAP30 and luffin-α: Novel ribosome-inactivating proteins induce plant systemic resistance against plant viruses.

Ribosome-inactivating proteins (RIPs) are toxic N-glycosylase that act on eukaryotic and prokaryotic rRNAs, resulting in arrest protein synthesis. RIPs are widely found in higher plant species and display strong antiviral activity. Previous studies have shown that PAP and α-MMC have antiviral activity against TMV. However, the localization of RIPs in plant cells and the mechanism by which RIPs activate plant defense against several plant viruses remain unclear. In this study, we obtained four RIPs (the C-terminal deletion mutant of pokeweed antiviral proteins (PAP-c), alpha-momorcharin (α-MMC), momordica anti-HIV protein of 30 kDa (MAP30) and luffin-α). The subcellular localization results indicated that these four RIPs were located on the plant cell membrane. Heterologous expression of RIPs (PAP-c, α-MMC, MAP30, luffin-α) enhanced tobacco mosaic virus (TMV) resistance in N. benthamiana. Compared with the control treatment, these RIPs significantly reduced the TMV content (149-357 fold) and altered the movement of TMV in the leaves of N. benthamiana. At the same time, heterologous expression of RIPs (MAP30 and luffin-α) could relieve TMV-induced oxidative damage, significantly inducing the expression of plant defense genes including PR1 and PR2. Furthermore, application of these RIPs could inhibit the infection of turnip mosaic virus (TuMV) and potato virus x (PVX). Therefore, this study demonstrated that MAP30 and luffin-α could be considered as new, effective RIPs for controlling plant viruses by activating plant systemic defense.

Fabrication of polydopamine reduced CuO nanoparticle-alginate composite nanogels for management of Pseudomonas synringae pv. tabaci in tobacco.

BACKGROUND: The wildfire disease on tobacco can seriously hinder plants. Meanwhile, its pathogen, Pseudomonas syringae, can also infect over 200 plants and threat agriculture production. However, the disease usually occurs after summer rains which washes away most copper (Cu)-based bactericides, allowing the disease to invade. Therefore, we fabricate a new nanogel with high disease control and anti-erosion ability and study the effects of the reductant on the performance of the copper oxide nanoparticle (CuONP) composite nanogel. RESULTS: Polydopamine (PDA) is a polycation for both in situ reduction of CuONP in alginate nanogels and for adjusting the copper ion (Cu2+ ) releasing rate in this work. The composite nanogel fabricated by PDA (PDA-CuONP@ALGNP@CTAC) had a higher Cu2+ releasing rate, damaging the pathogen membrane more efficiently, allowing for better disease control and plant growth promotion when compared to sodium borohydride (SBH)-fabricated nanogel (SBH-CuONP@ALGNP@CTAC) or the commercial bactericide, thiodiazole copper. The PDA-CuONP@ALGNP@CTAC had a high anti-erosion ability and could remain adhered to the leaf surface even after five rain event simulations. CONCLUSION: The addition of polycations (like PDA) into CuONP composite nanogel could increase the Cu2+ releasing rate, resulting in improved disease management when compared to SBH-CuONP@ALGNP@CTAC or thiodiazole copper. The PDA containing gel had an improved anti-erosion ability and water resistance. This new composite nanogel has a high potential for wildfire disease control, improving agricultural production. © 2022 Society of Chemical Industry.

Transcriptome analysis reveals the mechanism of zinc ion-mediated plant resistance to TMV in Nicotiana benthamiana.

Zinc ions (Zn2+) are used to promote plant growth and treat multiple diseases. However, it is still unclear which pathways in plants respond to Zn2+. In this study, we found that supplying (CH3COO)2Zn can effectively delay tobacco mosaic virus (TMV) replication and movement in Nicotiana benthamiana. To further understand the regulatory mechanism of antiviral activity mediated by Zn2+, we examined the transcriptomic changes of leaves treated with Zn2+. Three days after treatment, 7575 differential expression genes (DEGs) were enriched in the Zn2+ treatment group compared with the control group. Through GO and KEGG analysis, the pathway of phosphatidylinositol signaling system and inositol phosphate metabolism were significantly enriched after treated with Zn2+, and a large number of ethylene-responsive transcription factors (ERFs) involved in inositol phosphate metabolism were found to be enriched. We identified ERF5 performed a positive effect on plant immunity. Our findings demonstrated that Zn2+-mediated resistance in N. benthamiana activated signal transduction and regulated the expression of resistance-related genes. The results of the study uncover a global view of mRNA changes in Zn2+-mediated cellular processes involved in the competition between plants and viruses.

MiR-191 promotes the porcine immature Sertoli cell proliferation by targeting the BDNF gene through activating the PI3K/AKT signaling pathway.

The number of Sertoli cells in the testis is a major regulator on the sperm production capacity. MicroRNAs (miRNAs) participate in regulating the proliferation and apoptosis of porcine immature Sertoli cells. However, the functions and mechanisms of action of most identified miRNAs in porcine Sertoli cells remain largely unknown. In the present study, based on our previous results from an EdU-based high-content screening assay, we further studied the mechanism of action of miR-191 on the proliferation and apoptosis of porcine immature Sertoli cells through flow cytometry, Western blotting, and dual-luciferase activity analyses. The results demonstrated that overexpression of miR-191 promoted cell cycle progression from G1 phase to the S and G2 phases, enhanced cell proliferation, and inhibited apoptosis in the porcine immature Sertoli cells, whereasmiR-191 inhibition resulted in the opposite effects. The results from a luciferase reporter assay showed that miR-191 directly targeted the 3'-UTR of theBDNF gene. BDNF knockdown also promoted cell cycle progression to the S phase, cell proliferation and inhibited cell apoptosis, which were consistent with the effects of the miR-191overexpression. A co-transfection experiment showed that BDNF knockdown abolished the effects of miR-191 inhibition. Furthermore, both miR-191 overexpression and BDNFinhibition elevated the phosphorylation of PI3K and AKT, the key components of the PI3K/AKT signaling pathway, whereas BDNFinhibition offset the effects of the miR-191 knockdown. Overall, these data indicated that miR-191 promotes cell proliferation and inhibits apoptosis in porcine immature Sertoli cells by targeting theBDNF gene through activating the PI3K/AKT signaling pathway. This study provides a novel scientific basis for further investigation on the biological functions of miR-191 on porcine spermatogenesis.

Long non-coding RNA LINC00857 promotes gastric cancer cell proliferation and predicts poor patient survival.

Gastric cancer (GC) is a common malignancy worldwide and its pathogenesis remains unclear. Long non-coding RNAs (lncRNAs) serve an important function in cancer development, therefore identification of functional lncRNAs in GC is required. The results of the present study demonstrate that an lncRNA, LINC00857, was increased in GC tissues compared with adjacent non-tumor tissues. Overexpression of LINC00857 was positively associated with poor survival rate, as well as with the tumor size of patients with GC. LINC00857 knockdown induced by specific small interfering RNAs significantly inhibited GC cell proliferation in vitro. Genome-wide analysis revealed that LINC00857 knockdown deregulated the cell cycle. Western blot analysis confirmed that LINC00857 knockdown decreased protein expression of cyclin D1 and cyclin E1 in GC cells. Taken together, the results indicated that LINC00857 knockdown suppressed GC cell proliferation through deregulating the cell cycle, resulting in the downregulation of cyclin D1 and cyclin E1. Therefore, LINC00857 expression may be an independent biomarker for the diagnosis and prognosis of GC.

The role of ubiquitin-proteasome pathway in spermatogenesis.

Ubiquitin-proteasome pathway (UPP) is the main pathway of protein degradation in eukaryotic cells. The UPP plays very important roles in cell cycle progression, apoptosis, stress response and growth and development through regulating protein interaction, protein activity, protein localization and signal transduction. Previous studies have shown that the UPP is essential for regulating acrosome and tail biogenesis during spermatogenesis in human and animals. The dysregulation of UPP during spermatogenesis results in sperm deformity and reduced sperm motility and leads to reproductive system diseases such as oligospermatism, infertility and testicular tumors. In this review, we summarized the signal transduction and regulation mechanism of UPP in spermatogenesis, which may provide references for future studies.

Exposure to bisphenol A (BPA) in Wistar rats reduces sperm quality with disruption of ERK signal pathway.

Bisphenol A (BPA) is an estrogenic environmental toxin widely used in the production of plastics and ubiquitous human exposure to this chemical has been proposed to be a potential risk to human health. Exposure to BPA can negatively impact sperm quality. However, the mechanism remains largely unknown. The objectives of this study were to assess the role of BPA on sperm quality and explore the possible mechanisms. The Wistar male rats (aged 28 days) were administered BPA by oral gavage for 28 days at dose of 50, 100 and 200 mg/kg/day; meanwhile, the negative control with corn oil (0 mg/kg/day BPA) and positive control with E2 at the dose of 100 µg/kg/day. The sperm density, sperm activity and sperm survival rate were analyzed byCASA system, and the sperm abnormality rate was analyzed by improved Papanicolaou stained. The protein expression levels of Src/p-Src, ERK1/2, p-ERK1/2 and CREB/p-CREB were detected by Western bolt. The results showed that the body weight gain, testes weight, testis coefficient, sperm density, sperm activity, sperm survival rate and protein expression levels of p-ERK1, p-ERK2 and p-CREB decreased, but the sperm abnormality rate increased with increasing BPA concentrations. There were positive correlations between sperm density, sperm activity and sperm survival rate with protein expression levels of p-ERK1, p-ERK2 and p-CREB, and negative correlations between sperm abnormality rate with the protein expression levels of p-ERK1, p-ERK2 and p-CREB. Results from the structural equation model demonstrated that BPA retained a significant negative effect to p-ERK, whereas p-ERK retained a significant positive effect to sperm quality and acted as the mediate variable. This study provides a novel insight regarding the potential role of p-ERK1 and p-ERK2 protein kinase on reproductive toxicity of BPA. The adverse effects of BPA on adult male sperm quality may be through the induction of the disruption of ERK signal pathway. However, additional research is needed to confirm our findings and to further test the suggested potential mechanisms.

[Preparation and evaluation of pharmacodynamic of the pectin-doxorubicin conjugate nanosuspensions].

This study was conducted to produce pectin-doxorubicin conjugate（PDC） nanosuspensions by high-pressure homogenization, and investigating the physico-chemical properties, the cumulative release rate in vitro and in vivo, and the anti-tumor activity. The major production parameters such as pressure, cycle numbers and types of stabilizers on the mean particle size and polydispersity index（PI） of PDC nanosuspensions were investigated. The cumulative release rate in phosphate buffer saline（PBS） at pH 5.1 or 7.0 were studied. The concentration of doxorubicin（DOX） in plasma of rabbit were recorded after intraperitoneal injection of PDC nanosuspensions(DOX was equivalent to 10 mg·kg-1) or DOX (10 mg·kg-1). We established an animal model of the nude mice with SKOV3 cell, and injected the PDC nanosuspensions(DOX was equivalent to 10, 5, 2.5 mg·kg-1) in the first day, and observed the growth state of nude mice. The particle size of PDC nanosuspensions was 118.8 ± 6.93 nm, PI was 0.14 ± 0.03, as well as the zeta potential was -27.2 ± 0.36 m V. It shows that no drug release was found in PBS at p H 7.4. About 40% cumulative release was determined in PBS at 5.1 after 30 h. The concentration of DOX in plasma of PDC group was 60 ng·mL-1, and was lower than that of DOX group. Compared with control group, high-dose-group decreased the weight of nude mice's ascites tumor and burrknot. PDC nanosuspensions can inhibit the growth of SKOV3 cell line in nude mice.In summary, PDC nanosuspensions are target-specific drugs with high efficiency and low toxicity in the ascites cancer model.

BAFF enhances B-cell-mediated immune response and vaccine-protection against a very virulent IBDV in chickens.

Infectious bursal disease (IBD) is an acute, highly infectious and immunosuppressive disease caused by IBDV, which specifically targets destruction of B cells in the bursa of Fabricius. B-cell activating factor belonging to the TNF family (BAFF, also called BLyS, TALL-1, THANK, or zTNF4) is an important factor for B-cell proliferation and survival. Here we demonstrate that human soluble BAFF (hsBAFF) may enhance humoral immune response by elevating B lymphocyte activity of secretion of immunoglobulin (Ig) such as IgA, IgM and IgG in chickens immunized or unimmunized with an inactivated IBDV vaccine from a very virulent strain. Of importance, we found that hsBAFF, as a co-immunostimulant for vaccination, may play a vital role in amplifying the specific protective immune response, thereby potently preventing very virulent IBDV challenge. This is supported by serological evidence that hsBAFF may effectively enhance higher specific IgG activity and titre in serum of immunized chickens. The findings strongly suggest that BAFF may be exploited in combination with specific vaccination for prevention of IBD.