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SUMMARY: The successful interaction between pollen and stigma is a critical process for plant sexual reproduction, involving a series of intricate molecular and physiological events. After self‐compatible pollination, a significant reduction in reactive oxygen species (ROS) production has been observed in stigmas, which is essential for pollen grain rehydration and subsequent pollen tube growth. Several scavenging enzymes tightly regulate ROS homeostasis. However, the potential role of these ROS‐scavenging enzymes in the pollen‐stigma interaction in Brassica napus remains unclear. Here, we showed that the activity of ascorbate peroxidase (APX), an enzyme that plays a crucial role in the detoxification of hydrogen peroxide (H2O2), was modulated depending on the compatibility of pollination in B. napus. We then identified stigma‐expressed APX1s and generated pentuple mutants of APX1s using CRISPR/Cas9 technology. After compatible pollination, the BnaAPX1 pentuple mutants accumulated higher levels of H2O2 in the stigma, while the overexpression of BnaA09.APX1 resulted in lower levels of H2O2. Furthermore, the knockout of BnaAPX1 delayed the compatible response‐mediated pollen rehydration and germination, which was consistent with the effects of a specific APX inhibitor, ρ‐Aminophenol, on compatible pollination. In contrast, the overexpression of BnaA09.APX1 accelerated pollen rehydration and germination after both compatible and incompatible pollinations. However, delaying and promoting pollen rehydration and germination did not affect the seed set after compatible and incompatible pollination in APX1 pentuple mutants and overexpression lines, respectively. Our results demonstrate the fundamental role of BnaAPX1 in pollen rehydration and germination by regulating ROS homeostasis during the pollen‐stigma interaction in B. napus. Significance Statement: Our research found that self‐incompatibility in Brassica napus requires the accumulation of reactive oxygen species (ROS) levels in the stigma. We identified the importance of BnaAPX1 in regulating ROS homeostasis, which is critical for pollen rehydration and germination in B. napus. [ABSTRACT FROM AUTHOR]

Persistent human papillomavirus (HPV) infection is associated with multiple malignancies. Developing therapeutic vaccines to eliminate HPV‐infected and malignant cells holds significant value. In this study, we introduced a lipid nanoparticle encapsulated mRNA vaccine expressing tHA‐mE7‐mE6. Mutations were introduced into E6 and E7 of HPV to eliminate their tumourigenicity. A truncated influenza haemagglutinin protein (tHA), which binds to the CD209 receptor on the surface of dendritic cells (DCs), was fused with mE7‐mE6 in order to allow efficient uptake of antigen by antigen presenting cells. The tHA‐mE7‐mE6 (mRNA) showed higher therapeutic efficacy than mE7‐mE6 (mRNA) in an E6 and E7+ tumour model. The treatment resulted in complete tumour regression and prevented tumour formation. Strong CD8+ T‐cell immune response was induced, contributing to preventing and curing of E6 and E7+ tumour. Antigen‐specific CD8+ T were found in spleens, peripheral blood and in tumours. In addition, the tumour infiltration of DC and NK cells were increased post therapy. In conclusion, this study described a therapeutic mRNA vaccine inducing strong anti‐tumour immunity in peripheral and in tumour microenvironment, holding promising potential to treat HPV‐induced cancer and to prevent cancer recurrence. [ABSTRACT FROM AUTHOR]

Summary: Self‐incompatibility plays a vital role in angiosperms, by preventing inbreeding depression and maintaining genetic diversity within populations. Following polyploidization, many angiosperm species transition from self‐incompatibility to self‐compatibility.Here, we investigated the S‐locus in Brassicaceae and identified distinct origins for the sRNA loci, SMI and SMI2 (SCR Methylation Inducer 1 and 2), within the S‐locus. The SMI loci were found to be widespread in Cruciferae, whereas the SMI2 loci were exclusive to Brassica species.Additionally, we discovered four major S‐haplotypes (BnS‐1, BnS‐6, BnS‐7, and BnS‐1300) in rapeseed. Overexpression of BnSMI‐1 in self‐incompatible Brassica napus ('S‐70S1300S6') resulted in a significant increase in DNA methylation in the promoter regions of BnSCR‐6 and BnSCR‐1300, leading to self‐compatibility. Conversely, by overexpressing a point mutation of BnSmi‐1 in the 'S‐70S1300S6' line, we observed lower levels of DNA methylation in BnSCR‐6 and BnSCR‐1300 promoters. Furthermore, the overexpression of BnSMI2‐1300 in the 'SI‐326S7S6' line inhibited the expression of BnSCR‐7 through transcriptional repression of the Smi2 sRNA from the BnS‐1300 haplotype.Our study demonstrates that the self‐compatibility of rapeseed is determined by S‐locus sRNA‐mediated silencing of SCR after polyploidization, which helps to further breed self‐incompatible or self‐compatible rapeseed lines, thereby facilitating the utilization of heterosis. [ABSTRACT FROM AUTHOR]

To identify the process of tourism place making by using intangible cultural heritage (ICH) as the resource, this study conducts a qualitative meta‐analysis based on 23 European and 16 Chinese cases. The results conclude and replenish the main considerations in creating tourist destinations with ICH, including planner, ICH type, specific place making scope, purpose, design focus, types of placemaking, and sense of place. Findings reveal differentiated patterns and similar methods in the decision‐making process in the two regions. This article provides a new perspective on taking ICH as place making tool and sheds light on ICH resource development. [ABSTRACT FROM AUTHOR]

Multidrug resistance remains a great challenge for cancer chemotherapy. Herein, a biomimetic drug delivery system based on lemon‐derived extracellular vesicles (EVs) nanodrugs (marked with heparin‐cRGD‐EVs‐doxorubicin (HRED)) is demonstrated, achieving highly efficient overcoming cancer multidrug resistance. The HRED is fabricated by modifying functional heparin‐cRGD (HR) onto the surface of EVs and then by loading with doxorubicin (DOX). The obtained HRED enable to effectively enter DOX‐resistant cancer cells by caveolin‐mediated endocytosis (main), macropinocytosis (secondary), and clathrin‐mediated endocytosis (last), exhibiting excellent cellular uptake capacity. The diversified endocytosis capacity of HRED can efficiently dissipate intracellular energy and meanwhile trigger downstream production reduction of adenosine triphosphate (ATP), leading to a significant reduction of drug efflux. Consequently, they show excellent anti‐proliferation capacities to DOX‐resistant ovarian cancer, ensuring the efficiently overcoming ovarian cancer multidrug resistance in vivo. The authors believe this strategy provides a new strategy by endocytosis triggered‐energy dissipation and ATP production reduction to design drug delivery system for overcoming cancer multidrug resistance. [ABSTRACT FROM AUTHOR]

Four novel 5-acyloxyimino-5-deoxyavermectin B1 compounds have been synthesized from avermectin B1 by selective oxidization of the hydroxy group at C-5, followed by oximation and convenient esterification. Their structures were confirmed by IR, 1H NMR, 13C NMR and MS. Insecticidal activities of the intermediate oxime and the four new acyl derivatives were evaluated against Helicoverpa armigera, Spodoptera exigua and Musca domestica. [ABSTRACT FROM AUTHOR]

Background: The results of the esophageal body motility differences between liquid and solid swallows from high‐resolution manometry (HRM) studies are not consistent. The information of the frequency of ineffective liquid and solid bolus swallows in healthy individuals during HRM procedure is limited. The normative values of the HRM parameters of both liquid and solid swallows for Chinese population are lacking. Methods: The esophageal HRM data of 101 healthy volunteers from multicenters in China were analyzed. The values of the HRM parameters were summarized and compared between liquid and solid swallows. The frequencies of ineffective liquid and solid swallows were summarized. Results: Esophagus contracted stronger and slower in solid bolus swallows than water swallows with HREM. Ineffective water swallow (DCI < 450 mm Hg.s.cm) and ineffective bread swallow (DCI < 800 mm Hg.s.cm) were frequently seen in asymptomatic individuals. The adding of bread swallows to the HREM procedure might cause diagnostic change in about 15.8% (16/101) of the asymptomatic individuals. Conclusions: The vigor and velocity of the esophageal peristalsis between liquid and solid bolus swallows are different. Ineffective water and solid bolus swallows are not rare. Adding solid bolus swallows brings diagnostic change, and it may be needed routinely for the HRM procedure. [ABSTRACT FROM AUTHOR]