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Summary: The biotrophic fungal pathogen Blumeria graminis f. sp. tritici (Bgt) is a crucial factor causing reduction in global wheat production. Wild wheat relatives, for example Thinopyrum intermedium, is one of the wild‐used parents in wheat disease‐resistant breeding. From T. intermedium line, we identified the aspartic protease gene, TiAP1, which is involved in resistance against Bgt. TiAP1 is a secreted protein that accumulates in large amounts at the infection sites of Bgt and extends to the intercellular space. Yeast two‐hybrid, luciferase complementation imaging and bimolecular florescent complimentary analysis showed that TiAP1 interacted with the chitin deacetylase (BgtCDA1) of Bgt. The yeast expression, purification and in vitro test confirmed the chitin deacetylase activity of BgtCDA1. The bombardment and VIGS‐mediated host‐induced gene silencing showed that BgtCDA1 promotes the invasion of Bgt. Transcriptome analysis showed the cell wall xylan metabolism, lignin biosynthesis‐related and defence genes involved in the signal transduction were up‐regulated in the transgenic TiAP1 wheat induced by Bgt. The TiAP1 in wheat may inactivate the deacetylation function of BgtCDA1, cause chitin oligomers expose to wheat chitin receptor, then trigger the wheat immune response to inhibit the growth and penetration of Bgt, and thereby enhance the resistance of wheat to pathogens. [ABSTRACT FROM AUTHOR]

The coronavirus diseases 2019 (COVID-19) caused by the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 has caused more than 140 million infections worldwide by the end of April 2021. As an enveloped single-stranded positive-sense RNA virus, SARS-CoV-2 underwent constant evolution that produced novel variants carrying mutation conferring fitness advantages. The current prevalent D614G variant, with glycine substituted for aspartic acid at position 614 in the spike glycoprotein, is one of such variants that became the main circulating strain worldwide in a short period of time. Over the past year, intensive studies from all over the world had defined the epidemiological characteristics of this highly contagious variant and revealed the underlying mechanisms. This review aims at presenting an overall picture of the impacts of D614G mutation on virus transmission, elucidating the underlying mechanisms of D614G in virus pathogenicity, and providing insights into the development of effective therapeutics. [ABSTRACT FROM AUTHOR]

Heterotypic cell-in-cell structures (heCICs) are closely related to tumor development and progression, and have become a new frontier in life science research. Ras-related C3 botulinum toxin substrate 1 (Rac1) belongs to the classic Rho GTPase, which plays a key role in regulating the cytoskeleton and cell movement. To investigate the role and mechanism of Rac1 in the formation of heCICs, tumor cells and immune killer cells were labeled with cell-tracker, respectively, to establish the heCICs model. Upon treatment with the Rac1 inhibitor NSC23766, the formation of heCICs between tumor and immune cells was significantly reduced. The plasmid pQCXIP-Rac1-EGFP constructed by gene cloning was packaged into pseudoviruses that subsequently infect tumor cells to make cell lines stably expressing Rac1. As a result, the formation of heCICs was significantly increased upon Rac1 overexpression. These results demonstrated a promotive role of Rac1 in heCICs formation, which may facilitate treating cell-in-cell related diseases, such as tumors, by targeting Rac1.

Lung cancer is ranked as the leading cause of cancer-related death worldwide, and the development of novel biomarkers is helpful to improve the prognosis of non-small cell lung cancer (NSCLC). Cell-in-cell structures (CICs), a novel functional surrogate of complicated cell behaviors, have shown promise in predicting the prognosis of cancer patients. However, the CIC profiling and its prognostic value remain unclear in NSCLC. In this study, we retrospectively explored the CIC profiling in a cohort of NSCLC tissues by using the "Epithelium-Macrophage-Leukocyte" (EML) method. The distribution of CICs was examined by the Chi-square test, and univariate and multivariate analyses were performed for survival analysis. Four types of CICs were identified in lung cancer tissues, namely, tumor-in-tumor (TiT), tumor-in-macrophage (TiM), lymphocyte-in-tumor (LiT), and macrophage-in-tumor (MiT). Among them, the latter three constituted the heterotypic CICs (heCICs). Overall, CICs were more frequently present in adenocarcinoma than in squamous cell carcinoma ( P = 0.009), and LiT was more common in the upper lobe of the lung compared with other lobes ( P = 0.020). In univariate analysis, the presence of TiM, heCIC density, TNM stage, T stage, and N stage showed association with the overall survival (OS) of NSCLC patients. Multivariate analysis revealed that heCICs (HR = 2.6, 95% CI 1.25-5.6) and lymph node invasion (HR = 2.6, 95% CI 1.33-5.1) were independent factors associated with the OS of NSCLC. Taken together, we profiled the CIC subtypes in NSCLC for the first time and demonstrated the prognostic value of heCICs, which may serve as a type of novel functional markers along with classical pathological factors in improving prognosis prediction for patients with NSCLC., Competing Interests: None., (AJCR Copyright © 2023.)