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Wheat leaf rust fungus is an obligate parasitic fungus that can absorb nutrients from its host plant through haustoria and secrete effector proteins into host cells. The effector proteins are crucial factors for pathogenesis as well as targets for host disease resistance protein recognition. Exploring the role of effector proteins in the pathogenic process of Puccinia triticina Eriks. (Pt) is of great significance for unraveling its pathogenic mechanisms. We previously found that a cysteine-rich effector protein, Pt1641, is highly expressed during the interaction between wheat and Pt, but its specific role in pathogenesis remains unclear. Therefore, this study employed techniques such as heterologous expression, qRT-PCR analysis, and host-induced gene silencing (HIGS) to investigate the role of Pt1641 in the pathogenic process of Pt. The results indicate that Pt1641 is an effector protein with a secretory function and can inhibit BAX-induced programmed cell death in Nicotiana benthamiana. qRT-PCR analyses showed that expression levels of Pt1641 were different during the interaction between the high-virulence strain THTT and low-virulence strains FGD and Thatcher, respectively. The highest expression level in the low-virulence strain FGD was four times that of the high-virulence strain THTT. The overexpression of Pt1641 in wheat near-isogenic line TcLr1 induced callose deposition and H2O2 production on TcLr1. After silencing Pt1641 in the Pt low-virulence strain FGD on wheat near-isogenic line TcLr1, the pathogenic phenotype of Pt physiological race FGD on TcLr1 changed from ";" to "3", indicating that Pt1641 plays a non-toxic function in the pathogenicity of FGD to TcLr1. This study helps to reveal the pathogenic mechanism of wheat leaf rust and provides important guidance for the mining and application of Pt avirulent genes. [ABSTRACT FROM AUTHOR]

Effectors are considered to be virulence factors secreted by pathogens, which play an important role during host-pathogen interactions. In this study, the candidate effector Pt9226 was cloned from genomic DNA of Puccinia triticina (Pt) pathotype THTT, and there were six exons and five introns in the 877 bp sequence, with the corresponding open reading frame of 447 bp in length, encoding a protein of 148 amino acids. There was only one polymorphic locus of I142V among the six Pt pathotypes analyzed. Bioinformatics analysis showed that Pt9226 had 96.46% homology with the hypothetical putative protein PTTG_26361 (OAV96349.1) in the Pt pathotype BBBD. RT-qPCR analyses showed that the expression of Pt9226 was induced after Pt inoculation, with a peak at 36 hpi, which was 20 times higher than the initial expression at 0 hpi, and another high expression was observed at 96 hpi. No secretory function was detected for the Pt9226-predicted signal peptide. The subcellular localization of Pt9226Δsp-GFP was found to be multiple, localized in the tobacco leaves. Pt9226 could inhibit programmed cell death (PCD) induced by BAX/INF1 in tobacco as well as DC3000-induced PCD in wheat. The transient expression of Pt9226 in 26 wheat near-isogenic lines (NILs) by a bacterial type III secretion system of Pseudomonas fluorescens EtHAn suppressed callose accumulation triggered by Ethan in wheat near-isogenic lines TcLr15, TcLr25, and TcLr30, and it also suppressed the ROS accumulation in TcLr15. RT-qPCR analysis showed that the expression of genes coded for pathogenesis-related protein TaPR1, TaPR2, and thaumatin-like protein TaTLP1, were suppressed, while the expression of PtEF-1α was induced, with 1.6 times at 72 h post inoculation, and TaSOD was induced only at 24 and 48 h compared with the control, when the Pt pathotype THTT was inoculated on a transient expression of Pt9226 in wheat TcLr15. Combining all above, Pt9226 acts as a virulence effector in the interaction between the Pt pathotype THTT and wheat. [ABSTRACT FROM AUTHOR]

Ferrocenyl derivatives and organometallic iridium(III) complexes have been prospective substitutes for platinum-based anticancer drugs. Eight half-sandwich iridium(III) ferrocene-thiosemicarbazide (Fc-TSC) Schiff base anticancer complexes were prepared in this study. These complexes displayed a dimeric structure and exhibited a particular fluorescence due to the "enol" orientation of the TSC pro-ligand. An energy-dependent pathway of the uptake mechanism was ascertained, which ended in the lysosome and led to lysosome damage and apoptosis. Flow cytometry confirmed that the complexes could block the cell cycle (G1 phase) and improve the levels of intracellular reactive oxygen species, indicating an anticancer mechanism of oxidation. Then, a lysosomal–mitochondrial anticancer pathway was verified through western blotting. In vivo toxicity assays confirmed that these complexes showed better anti-migration ability and less toxicity in comparison to cisplatin. Thus, these complexes provide a new strategy for the design of non-platinum organometallic anticancer drugs. [ABSTRACT FROM AUTHOR]

Summary Thaumatin‐like proteins (TLPs) in plants play a crucial role in combating stress, and they have been proven to possess antifungal properties. However, the role of TLPs in pathogens has not been reported. We identified a effector protein, Pt9029, which contained a Thaumatin domain in Puccinia triticina (Pt), possessing a chloroplast transit peptide and localized in the chloroplasts. Silencing Pt9029 in the Pt physiological race THTT resulted in a notable reduction in virulence and stunted growth and development of Pt hypha in near‐isogenic wheat line TcLr2b. Overexpression of Pt9029 in wheat exerted a suppressive effect on H2O2 production, consequently impeding the wheat's disease resistance mechanisms. The TLP domain of Pt9029 targets the Rubisco activase (TaRCA) in chloroplasts. This interaction effectively inhibited the function of TaRCA, subsequently leading to a decrease in Rubisco enzyme activity. Therefore, this indicates that TLPs in Pt can inhibit host defense mechanisms during the pathogenic process of Pt. Moreover, TaRCA silencing resulted in reduced resistance of TcLr2b against Pt race THTT. This clearly demonstrated that TaRCA positively regulates wheat resistance to leaf rust. These findings reveal a novel strategy exploited by Pt to manipulate wheat rust resistance and promote pathogenicity. [ABSTRACT FROM AUTHOR]

Fungal plant pathogens use proteinaceous effectors as well as newly identified secondary metabolites (SMs) and small non-coding RNA (sRNA) effectors to manipulate the host plant's defense system via diverse plant cell compartments, distinct organelles, and many host genes. However, most molecular studies of plant–fungal interactions have focused on secreted effector proteins without exploring the possibly equivalent functions performed by fungal (SMs) and sRNAs, which are collectively known as "non-proteinaceous effectors". Fungal SMs have been shown to be generated throughout the plant colonization process, particularly in the early biotrophic stages of infection. The fungal repertoire of non-proteinaceous effectors has been broadened by the discovery of fungal sRNAs that specifically target plant genes involved in resistance and defense responses. Many RNAs, particularly sRNAs involved in gene silencing, have been shown to transmit bidirectionally between fungal pathogens and their hosts. However, there are no clear functional approaches to study the role of these SM and sRNA effectors. Undoubtedly, fungal SM and sRNA effectors are now a treasured land to seek. Therefore, understanding the role of fungal SM and sRNA effectors may provide insights into the infection process and identification of the interacting host genes that are targeted by these effectors. This review discusses the role of fungal SMs and sRNAs during plant-fungal interactions. It will also focus on the translocation of sRNA effectors across kingdoms, the application of cross-kingdom RNA interference in managing plant diseases and the tools that can be used to predict and study these non-proteinaceous effectors. [ABSTRACT FROM AUTHOR]

Two new monomers were prepared by the reaction of 2-allylphenol and 4,4′-biphenyldicarbonyl chloride under different reaction conditions. The monomers were characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The curing processes of N, N -4,4′-bismaleimidodiphenylmethyene with 4,4′-bis(2-allylphenyl) biphenyldicarbonylate (BABC) and 4,4′-bis(2-propenylphenyl benzoate) ether (BPBE) were studied by rheological analysis and differential scanning calorimetry. Melting points of two monomers, BABC and BPBE, are 64°C and 121°C, respectively. The ABMI [4,4′-bis(2-allylphenyl)biphenyl bismaleimide] and PBMI [4,4′-bis(2-propenylphenyl)biphenyl bismaleimide] resins showed exothermic peaks at 233°C and 204°C, respectively. The measured melting points are significantly lower than that of the traditional bismaleimide resin which is modified by allyl bisphenol A. Dynamic mechanical analysis of the materials showed glass transition temperatures of ABMI and PBMI to be in the range of 213–258°C and 302–339°C, respectively. Thermogravimetric analysis of the cured resins showed 5% weight loss for ABMI and PMBI at 437°C and 428°C, along with char residues of 35.6–39.5%, respectively, at 800°C under nitrogen atmosphere. Furthermore, dielectric constants of propenyl-modified resins were lower (2.46–3.10) with dissipation factors of 0.0034–0.0036, compared with those of allyl bisphenol A resins. [ABSTRACT FROM AUTHOR]

Herein, we report an easy-to-prepare polyamic acid salt (PAAS) hydrogel with multiple functionalities including rapid self-healing, stimuli-responsive properties, and conductivity. This study describes a method for synthesizing PAAS hydrogel in aqueous solution. Phenylenediamine and 3,3′,4,4′-biphenyltetracarboxylic dianhydride were used to prepare a hydrogel with a fully aromatic backbone via gradual polymerization. It is possible to use the gel in the field of biomaterials in the absence of organic solvents. The prepared hydrogel was characterized using Fourier-transform infrared spectroscopy and dynamic rheometry. The gel has good toughness and the storage modulus and tensile stress are, respectively, about 0.25 and 0.45 MPa. Our study may pave the way for the manufacture of PAAS hydrogel, which may promote the development of hydrogel materials. [ABSTRACT FROM AUTHOR]

A series of acetylene-terminated isoimide and imide oligomers were prepared based on 2,3,3′,4′-biphenyltetracarboxylic dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, 3,4′-oxydianiline, and 1,3-bis(3-aminophenoxy)benzene as monomers. 3-Ethynylaniline was used as an end-capping reagent and trifluoroacetic anhydride served as a dehydrating agent. The main oligomer structures were confirmed by Fourier transform infrared spectroscopy, and the thermal imidization was characterized by differential scanning calorimetry. All uncured isoimide and imide oligomers exhibit excellent solubility characteristics in organic solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone, and most of the oligomers can be dissolved in low boiling point solvents such as acetone and ethyl acetate (more than 45 wt%). In comparison with imide analogs, the isoimide oligomers exhibited an increased solubility in low boiling point solvents which can be attributed to their unique asymmetric structures. The properties of the cured films and adhesives were evaluated by dynamic mechanical thermal analysis, thermogravimetric analysis, as well as tensile shear strength tests of the polymer adhesives. The cured films exhibited extremely high glass transition temperatures (Tg) of up to 341.6°C and 5% weight loss temperatures (Td5) of up to 518.2°C in a nitrogen atmosphere. Taken in concert, the results obtained indicate that all cured films featured an excellent thermal stability and a particularly high thermal-oxidative stability. One of these oligomers was selected and formulated to form a thermosetting adhesive for further investigation of the adhesion properties. This was done in an effort to improve the high-temperature performance characteristics of composite materials. [ABSTRACT FROM AUTHOR]

The intratumor microbiota results in the immunosuppressive microenvironment and facilitates tumor growth and metastasis. However, developing a synergistic therapy with antitumor, antibacterial, and antimetastatic effects faces enormous challenges. Here, we propose an metal chelation therapy to effectively eliminate tumor and intratumor bacteria and suppress tumor metastasis. Different from traditional chelation therapy that only consumes metal elements, this therapy not only eliminates the crucial metal elements for tumor metabolism but also releases new metal ions with antitumor and antibacterial properties. Based on the high demand for copper in breast cancer, we prepare a fibrous therapeutic nanoagent (Zn-PEN) by chelating D-Penicillamine (D-PEN) with Zn2+. Firstly, Zn-PEN achieves dual inhibition of oxidative phosphorylation and glycolysis metabolism  through copper depletion and Zn2+ activated cGAS-STING pathway, thus inducing tumor cell death. Secondly, Zn-PEN has the capability to eradicate Fusobacterium nucleatum in breast cancer, thereby mitigating its immunosuppressive impact on the tumor microenvironment. Finally, Zn-PEN effectively inhibits tumor metastasis through multiple routes, including the inhibition of epithelial-mesenchymal transition process, activation of cGAS-STING pathway, and elimination with F. nucleatum. Therefore, we verify the feasibility of Zn-PEN mediated metal chelation therapy in a 4T1 model infected with F. nucleatum, providing a new therapeutic strategy for inhibiting tumor metastasis., (© 2024 Wiley‐VCH GmbH.)

An improved phase generated carrier arctangent demodulation algorithm based on harmonic mixing and phase quadrature technology (PGC-Arctan-HP) is proposed in this paper, which can eliminate the effects of modulation depth shift, carrier phase delay, and light intensity disturbance (LID) on the demodulation results. The simulation results are consistent with theoretical analysis, and indicate that the PGC-Arctan-HP algorithm can achieve optimal demodulation compared with other demodulation algorithms. The results of interferometric experiments show that the demodulated waveforms of the improved algorithm are relatively stable with an amplitude error of 0.0294%. The total-harmonic-distortion (THD) and the signal-to-noise-and-distortion (SINAD) can reach -60.0286 dB and 59.5388 dB.

Ferrocenyl derivatives and organometallic iridium(III) complexes have been prospective substitutes for platinum-based anticancer drugs. Eight half-sandwich iridium(III) ferrocene-thiosemicarbazide (Fc-TSC) Schiff base anticancer complexes were prepared in this study. These complexes displayed a dimeric structure and exhibited a particular fluorescence due to the "enol" orientation of the TSC pro-ligand. An energy-dependent pathway of the uptake mechanism was ascertained, which ended in the lysosome and led to lysosome damage and apoptosis. Flow cytometry confirmed that the complexes could block the cell cycle (G1 phase) and improve the levels of intracellular reactive oxygen species, indicating an anticancer mechanism of oxidation. Then, a lysosomal-mitochondrial anticancer pathway was verified through western blotting. In vivo toxicity assays confirmed that these complexes showed better anti-migration ability and less toxicity in comparison to cisplatin. Thus, these complexes provide a new strategy for the design of non-platinum organometallic anticancer drugs.