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To ascertain the effect of low-light stress (80 μmol·m−2·s−1) on cucumbers, we report on improving and breeding low-light-tolerant varieties by mining genes related to low-light tolerance. In this study, the quantitative trait locus (QTL) mapping of cucumber plant height and internode length under low-light stress was conducted using the F2 population, employing specific-length amplified fragment sequencing (SLAF-seq) and phenotypic analysis. A genetic map with a total length of 1114.29 c M was constructed from 1,076,599 SNPs, and 2233 single-nucleotide polymorphism (SNP) markers were distributed on seven linked groups, with an average map distance of 0.50 c M. Two QTLs related to plant height, CsPlH5.1 and CsPlH6.1, were detected on Chr.5 and Chr.6, with a cumulative contribution rate of 16.33%. The contribution rate (PVE), max LOD value, additive effect (ADD), and dominant effect (DOM) of CsPlH5.1 were 9.446%, 4.013, 1.005, and 0.563, respectively. CsPlH5.1 was located between 4,812,907 and 5,159,042 in the Gy14_V2.0 genome of cucumber, with a genetic distance of 0.32 Mb; the interval contained 41 candidate genes, and CsPlH6.1 was found to be located between Marker537985 (171.10 c M) and Marker537984 (171.55 c M), a range containing only one candidate gene. A total of 42 candidate genes related to photosynthesis, chloroplast development, abiotic stress, and plant growth were found in the location range associated with plant height. Simultaneously, a QTL (Csnd2_NdL6.1) for the second internode length was detected, and the max LOD, ADD, and DOM values were 5.689, 0.384, and −0.19, respectively. Csnd2_NdL6.1 was located between 29,572,188 and 29,604,215, with 0.03 Mb on Chr.6 including seven candidate genes. The molecular function of the CsGy6G032300 gene is involved with the binding of calcium ions, which may be related to the elongation and growth of plants; however, the population needs to be further expanded for acceptable localization verification. The results of this study provide a preliminary basis for the mining of essential genes of cucumber's low-light tolerance and identifying low-light-tolerance genes. [ABSTRACT FROM AUTHOR]

The cellular transmembrane protein MARCH8 impedes the incorporation of various viral envelope glycoproteins, such as the HIV-1 envelope glycoprotein (Env) and vesicular stomatitis virus G-glycoprotein (VSV-G), into virions by downregulating them from the surface of virus-producing cells. This downregulation significantly reduces the efficiency of virus infection. In this study, we aimed to further characterize this host protein by investigating its species specificity and the domains responsible for its antiviral activity, as well as its ability to inhibit cell-to-cell HIV-1 infection. We found that the antiviral function of MARCH8 is well conserved in the rhesus macaque, mouse, and bovine versions. The RING-CH domains of these versions are functionally important for inhibiting HIV-1 Env and VSV-G-pseudovirus infection, whereas tyrosine motifs are crucial for the former only, consistent with findings in human MARCH8. Through analysis of chimeric proteins between MARCH8 and non-antiviral MARCH3, we determined that both the N-terminal and C-terminal cytoplasmic tails, as well as presumably the N-terminal transmembrane domain, of MARCH8 are critical for its antiviral activity. Notably, we found that MARCH8 is unable to block cell-to-cell HIV-1 infection, likely due to its insufficient downregulation of Env. These findings offer further insights into understanding the biology of this antiviral transmembrane protein. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is a degenerative neurological disease that was discovered and named over a century ago. There are currently more than 20 million people with Alzheimer's disease worldwide, but unfortunately, due to the complexity of the causative mechanisms, there is still no accurate research conclusion on the causes of Alzheimer's disease. Andrographolide, the main active ingredient of the natural plant Andrographis paniculata, has shown good potential as a traditional anti-inflammatory drug for the treatment of Alzheimer's disease and in the field of neuroprotection. Therefore, it is necessary to explore the potential targets for the anti-Alzheimer's activity of andrographolide, including through molecular docking, and in turn to explore the potential of andrographolide and its derivatives as therapeutic agents for Alzheimer's disease. [ABSTRACT FROM AUTHOR]

MARCH8 is a member of the recently discovered MARCH family of RING-finger E3 ubiquitin ligases, 11 members of which have been identified and found to share a similar structure. The [...], Membrane-associated RING-ON 8 (MARCH8) is one of 11 members of the recently discovered MARCH family of RING (really interesting new gene)-finger E3 ubiquitin ligases (1,2). MARCH8 downregulates several host transmembrane proteins, including major histocompatibility complex (MHC)-II, CD86, interleukin (IL)-1 receptor accessory protein, TNF-related apoptosis-inducing ligand (TRAIL) receptor 1 and the transferrin receptor (3-7). However, its physiological roles remain largely unknown. Here we identify MARCH8 as a novel antiviral factor. The ectopic expression of MARCH8 in virus-producing cells does not affect levels of lentivirus production, but it does markedly reduce viral infectivity. MARCH8 blocks the incorporation of HIV-1 envelope glycoprotein into virus particles by downregulating it from the cell surface, probably through their interaction, resulting in a substantial reduction in the efficiency of viral entry. The inhibitory effect of MARCH8 on vesicular stomatitis virus G-glycoprotein is even more remarkable, suggesting a broad-spectrum inhibition of enveloped viruses by MARCH8. Notably, the endogenous expression of MARCH8 is high in monocyte-derived macrophages and dendritic cells, and MARCH8 knockdown or knockout in macrophages significantly increases the infectivity of virions produced by these cells. Our findings thus indicate that MARCH8 is highly expressed in terminally differentiated myeloid cells, and that it is a potent antiviral protein that targets viral envelope glycoproteins and reduces their incorporation into virions.

The report of the 20th National Congress of the Communist Party of China pointed out the initiative of 'accelerating the transformation of the development mode of super-large and mega cities.' The digital economy has broken the spatial limitation of the agglomeration effect and provided new insights into the transformation of the development mode of super-large and mega cities. Based on the theoretical analysis of the mechanism of the digital economy on the carrying capacity of cities, we empirically tested the short-term and long-term dynamic relationship between the digital economy and the carrying capacity of cities by constructing an index system of the digital economy and the carrying capacity of cities and adopting the vector error correction model (VECM). Furthermore, based on the perspective of new economic geography, we used the listing information of digital economy-related enterprises in Beijing from 2010 to 2020 for this study. The spatial evolution of digital economy-related enterprises in Beijing was analyzed by using the weighted mean center analysis (WMC) and the standard deviation ellipse analysis (SDE) methods. The results showed that: 1 The digital economy could significantly improve the carrying capacity of super-large and mega cities through the paths of optimizing employment structure, creating job opportunities, improving transportation efficiency, and online scene substitution. However, there would be a certain lag, and this impact would gradually increase over time. 2 The digital economy could play a strong centrifugal role and promote the diffusion of related economic activities to the periphery of cities, thus reducing the bearing pressure on the central urban area and thus breaking through the traditional 'center-periphery' theory to a certain extent. In conclusion, the digital economy can promote the management of 'big city disease' by enhancing the carrying capacity of cities and relieving the carrying pressure of central urban areas, thus providing a scientific basis for adjusting the population policy of super-large and mega cities and optimizing the development strategies of urban and rural areas. Accordingly, this study suggests that a comprehensive approach should be taken to promote the development of the digital economy in super-large and mega cities, the digital transformation of enterprises in these cities, the digital service capacity of the government, and the urban integration capacity of disadvantaged groups in urban areas, so as to fully utilize the role of the digital economy in promoting the carrying capacity of super-large and mega cities and achieve their high-quality and sustainable development. [ABSTRACT FROM AUTHOR]

Photocatalytic performance can be optimized via introduction of reactive sites. However, it is practically difficult to engineer these on specific photocatalyst surfaces, because of limited understanding of atomic‐level structure‐activity. Here we report a facile sonication‐assisted chemical reduction for specific facets regulation via oxygen deprivation on Bi‐based photocatalysts. The modified Bi2MoO6 nanosheets exhibit 61.5 and 12.4 μmol g−1 for CO and CH4 production respectively, ≈3 times greater than for pristine catalyst, together with excellent stability/reproducibility of ≈20 h. By combining advanced characterizations and simulation, we confirm the reaction mechanism on surface‐regulated photocatalysts, namely, induced defects on highly‐active surface accelerate charge separation/transfer and lower the energy barrier for surface CO2 adsorption/activation/reduction. Promisingly, this method appears generalizable to a wider range of materials. [ABSTRACT FROM AUTHOR]

The aggravating extreme climate changes and natural disasters stimulate the exploration of low‐carbon/zero‐carbon alternatives to traditional carbon‐based fossil fuels. Solar‐to‐hydrogen (STH) transformation is considered as appealing route to convert renewable solar energy into carbon‐free hydrogen. Restricted by the low efficiency and high cost of noble metal cocatalysts, high‐performance and cost‐effective photocatalysts are required to realize the realistic STH transformation. Herein, the 2D FePS3 (FPS) nanosheets anchored with TiO2 nanoparticles (TiO2/FePS3) are synthesized and tested for the photocatalytic hydrogen evolution reaction. With the integration of FPS, the photocatalytic H2‐evolution rate on TiO2/FePS3 is radically increased by ≈1686%, much faster than that of TiO2 alone. The origin of the greatly raised activity is revealed by theoretical calculations and various advanced characterizations, such as transient‐state photoluminescence spectroscopy/surface photovoltage spectroscopy, in situ atomic force microscopy combined with Kelvin probe force microscopy (AFM‐KPFM), in situ X‐ray photoelectron spectroscopy (XPS), and synchrotron‐based X‐ray absorption near edge structure. Especially, the in situ AFM‐KPFM and in situ XPS together confirm the electron transport pathway in TiO2/FePS3 with light illumination, unveiling the efficient separation/transfer of charge carrier in TiO2/FePS3 step‐scheme heterojunction. This work sheds light on designing and fabricating novel 2D material‐based S‐scheme heterojunctions in photocatalysis. [ABSTRACT FROM AUTHOR]

Membrane‐associated RING‐CH (MARCH) family member proteins are RING‐finger E3 ubiquitin ligases that are known to downregulate cellular transmembrane proteins. MARCH8 is a novel antiviral factor that inhibits HIV‐1 envelope glycoprotein and vesicular stomatitis virus G by downregulating these envelope glycoproteins from the cell surface, resulting in their reduced incorporation into virions. More recently, we have found that MARCH8 reduces viral infectivity via two different mechanisms. Additionally, several groups have reported further antiviral or virus‐supportive functions of the MARCH8 protein and its other cellular mechanisms. In this review, we summarize the current knowledge about the molecular mechanisms by which MARCH8 can regulate cellular homeostasis and inhibit and occasionally support enveloped virus infection. [ABSTRACT FROM AUTHOR]