PcAvh87, a virulence essential RxLR effector of Phytophthora cinnamomi suppresses host defense and induces cell death in plant nucleus.

Plants have developed intricate immune mechanisms to impede Phytophthora colonization. In response, Phytophthora secretes RxLR effector proteins that disrupt plant defense and promote infection. The specific molecular interactions through which Phytophthora RxLR effectors undermine plant immunity, however, remain inadequately defined. In this study, we delineate the role of the nuclear-localized RxLR effector PcAvh87, which is pivotal for the full virulence of Phytophthora cinnamomi. Gene expression analysis indicates that PcAvh87 expression is significantly upregulated during the initial infection stages, interacting with the immune responses triggered by the elicitin protein INF1 and pro-apoptotic protein BAX. Utilizing PEG/CaCl2-mediated protoplast transformation and CRISPR/Cas9-mediated gene editing, we generated PcAvh87 knockout mutants, which demonstrated compromised hyphal growth, sporangium development, and zoospore release, along with a marked reduction in pathogenicity. This underscores PcAvh87's crucial role as a virulence determinant. Notably, PcAvh87, conserved across the Phytophthora genus, was found to modulate the activity of plant immune protein 113, thereby attenuating plant immune responses. This implies that the PcAvh87-mediated regulatory mechanism could be a common strategy in Phytophthora species to manipulate plant immunity. Our findings highlight the multifaceted roles of PcAvh87 in promoting P. cinnamomi infection, including its involvement in sporangia production, mycelial growth, and the targeting of plant immune proteins to enhance pathogen virulence.

Ratiometric fluorescence sensor based on deep learning for rapid and user-friendly detection of tetracycline antibiotics.

The detection of tetracycline antibiotics (TCs) in food holds great significance in minimizing their absorption within the human body. Hence, this study aims to develop a rapid, convenient, real-time, and accurate detection method for detecting antibiotics in an authentic market setting. A colorimetric fluorescence sensor was devised for tetracycline detection utilizing PVA aerogels as the substrate. Its operating principle is based on the IFE effect and antenna effect. A detection device is designed to capture fluorescence images while deep learning was employed to aid in the detection process. The sensor exhibits high responsiveness with a mere 60-s requirement for detection and demonstrates substantial color changes(blue to red), achieving 99% accuracy within the range of 10-100 µM with the assistance of deep learning (Resnet18). Real sample simulation tests yielded recovery rates between 95% and 130%. Overall, the proposed strategy proved to be a simple, portable, reliable, and responsive solution for rapid real-time TCs detection in food samples.

Effects of HSP70 Antisense Oligonucleotide on the Proliferation and Apoptosis of Human Hepatocellular Carcinoma Cells / 华中科技大学学报（医学）（英德文版）

The study investigated the effects of heat shock protein 70(HSP70)antisense oligonucleotide (ASODN)on the proliferation and apoptosis of a human hepatocellular carcinoma cell line(SMMC-7721 cells)in vitro.HSPT0 oligonucleotide was transfected into SMMC-7721 cells by the mediation of SofastTM transfection reagent.Inhibition rate of SMMC-7721 cells was determined by using MTT method.Apoptosis rate and cell cycle distribution were measured by flow cytometry.Immunocytochemistry staining was used to observe the expression of HSP70,Bcl-2 and Bax.The results showed that HSP70 ASODN at various concentrations could significantly inhibit the growth of SMMC-7721cells,and the inhibition effect peaked 48 h after transfection with 400-nmol/L HSP70 ASODN.Cytometric analysis showed the apoptotic rate was increased in a dose-and time-dependent manner in the HSP70 ASODN-treated cells.The percentage of cells in the G2/M and S phases was significantly decreased and that in the G0/G1 phase increased as the HSP70 ASODN concentration was elevated and the exposure time prolonged.Immunocytochemistry showed that treatment of SMMC-7721 cells with HSP70 ASODN resulted in decreased expressions of HSP70 and Bcl-2 proteins,and an increased expression of Bax protein.It was concluded that the HSP70 ASODN can inhibit the growth of the SMMC-7721 cells and increase cell apoptosis by down-regulating the expression of HSP70.HSP70ASODN holds promise for the treatment of hepatocellular carcinoma.