Yellow Petal locus GaYP promotes flavonol biosynthesis and yellow coloration in petals of Asiatic cotton (Gossypium arboreum).

KEY MESSAGE: Yellow Petal locus GaYP is located on chromosome 11 and encodes a Sg6 R2R3-MYB transcription factor, which promotes flavonol biosynthesis and yellow coloration in Asiatic cotton petals. Petal color is pivotal to ornamental value and reproduction of plants. Yellow coloration in plant petals is mainly attributed to colorants including carotenoids, aurones and some flavonols. To date, the genetic regulatory mechanism of flavonol biosynthesis in petals is still to be elucidated. Here, we employed Asiatic cottons with or without deep yellow coloration in petals to address this question. Multi-omic and biochemical analysis revealed significantly up-regulated transcription of flavonol structural genes and increased levels of flavonols, especially gossypetin and 6-hydroxykaempferol, in yellow petals of Asiatic cotton. Furthermore, the Yellow Petal gene (GaYP) was mapped on chromosome 11 by using a recombinant inbred line population. It was found that GaYP encoded a transcriptional factor belonging to Sg6 R2R3-MYB proteins. GaYP could bind to the promoter of flavonol synthase gene (GaFLS) and activate the transcription of downstream genes. Knocking out of GaYP or GaFLS homologs in upland cotton largely eliminated flavonol accumulation and pale yellow coloration in petals. Our results indicated that flavonol synthesis, up-regulated by the R2R3-MYB transcription activator GaYP, was the causative factor for yellow coloration of Asiatic cotton petals. In addition, knocking out of GaYP homologs also led to decrease in anthocyanin accumulation and petal size in upland cotton, suggesting that GaYP and its homologs might modulate developmental or physiological processes beyond flavonol biosynthesis.

Enhanced photocatalytic activity of Ag@g-C3N4 nanotubes by regulating photogenerated carriers to bypass the recombination center under the Lorentz force.

Photocatalysis, as a form of solar energy conversion, has considerable development prospects for solving energy exhaustion and environmental pollution. Promoting the utilisation of photocarriers is the key way to enhance photocatalytic activity and quantum efficiency. The g-C3N4 with the width of the band gap responsive to visible light, which is a great concern for researchers, was prepared by thermal decomposition and the insides were stripped from the outer wall and then curled to form the nanotubes (NTs), microtubes and shorten the migration distance of the electrons and holes. To promote the separation of the photocarriers in the g-C3N4, Ag particles are deposited by photoreduction as electron "traps" with surface plasmon resonance (SPR), and an external magnetic field is introduced during the photocatalysis. Under the Lorentz force, the photocatalytic efficiency of the Ag@g-C3N4 NTs is 200% higher than that of bulk g-C3N4, as a result of being able to prolong the life of the photogenerated carriers to bypass the recombination sites.

Association between mental health and community support in lockdown communities during the COVID-19 pandemic: Evidence from rural China.

Governments worldwide have taken unprecedented social distancing and community lockdown measures to halt the COVID-19 epidemic, leaving millions of people restrained in locked-down communities and their mental well-being at risk. This study examines Chinese rural residents' mental health risk under emergency lockdown during the COVID-19 pandemic. It investigates how the environmental, socioeconomic, and behavioral dimensions of community support affect mental health in this emergency context. We also explore whether community support's effectiveness depends on the strictness of lockdown measures implemented and the level of individual perceived COVID-19 infection risk. We collect self-reported mental health risk, community support, and demographics information through a cross-sectional survey of 3892 Chinese rural residents living in small towns and villages. Ordinary least square regressions are employed to estimate the psychological effects of community support. The results suggest that the COVID-19 epidemic and lockdown policies negatively affect psychological well-being, especially for rural females. The capacity for community production has the largest impact on reducing mental health risks, followed by the stability of basic medical services, community cohesion, housing condition, the stability of communications and transportation supply, and the eco-environment. The effectiveness of different community support dimensions depends on the level of lockdown policy implemented and the levels of one's perceived risk of COVID-19 infection. Our study stresses the psychological significance of a healthy living environment, resilient infrastructure and public service system, and community production capacity during the lockdown in rural towns and villages.

Phytochemical diversity and their adaptations to abiotic and biotic pressures in fine roots across a climatic gradient.

Phytochemicals and their ecological significance are long ignored in trait-based ecology. Moreover, the adaptations of phytochemicals produced by fine roots to abiotic and biotic pressures are less understood. Here, we explored the fine roots metabolomes of 315 tree species and their rhizosphere microbiome in southwestern China spanning tropical, subtropical, and subalpine forest ecosystems, to explore phytochemical diversity and endemism patterns of various metabolic pathways and phytochemical-microorganism interactions. We found that subalpine species showed higher phytochemical diversity but lower interspecific variation than tropical species, which favors coping with high abiotic pressures. Tropical species harbored higher interspecific phytochemical variation and phytochemical endemism, which favors greater species coexistence and adaptation to complex biotic pressures. Moreover, there was evidence of widespread chemical niche partitioning of closely related species in all regions, and phytochemicals showed a weak phylogenetic signal, but were regulated by abiotic and biotic pressures. Our findings support the Latitudinal Biotic Interaction Hypothesis, i.e., the intensity of phytochemical-microorganism interactions decreases from tropical to subalpine regions, which promotes greater microbial community turnover and phytochemical niche partitioning of host plants in the tropics than in higher latitude forests. Our study reveals the convergent phytochemical diversity patterns of various pathways and their interactions with microorganism, thus promoting species coexistence.

MARCH8 inhibits pseudorabies virus replication by trapping the viral cell-to-cell fusion complex in the trans-Golgi network.

The membrane-associated RING-CH 8 protein (MARCH8), a member of the E3 ubiquitin ligase family, has broad-spectrum antiviral activity. However, some viruses hijack MARCH8 to promote virus replication, highlighting its dual role in the viral lifecycle. Most studies on MARCH8 have focused on RNA viruses, leaving its role in DNA viruses largely unexplored. Pseudorabies virus (PRV) is a large DNA virus that poses a potential threat to humans. In this study, we found that MARCH8 inhibited PRV replication at the cell-to-cell fusion stage. Interestingly, our findings proved that MARCH8 blocks gB cleavage by recruiting furin but this activity does not inhibit viral infection in vitro. Furthermore, we confirmed that MARCH8 inhibits cell-to-cell fusion independent of its E3 ubiquitin ligase activity but dependent on the interaction with the cell-to-cell fusion complex (gB, gD, gH, and gL). Finally, we discovered that the distribution of the cell-to-cell fusion complex is significantly altered and trapped within the trans-Golgi network. Overall, our results indicate that human MARCH8 acts as a potent antiviral host factor against PRV via trapping the cell-to-cell fusion complex in the trans-Golgi network.

MARCH1 and MARCH2 inhibit pseudorabies virus replication by trapping the viral cell-to-cell fusion complex in trans-Golgi network.

The membrane-associated RING-CH (MARCH) family of proteins are members of the E3 ubiquitin ligase family and are essential for a variety of biological functions. Currently, MARCH proteins are discovered to execute antiviral functions by directly triggering viral protein degradation or blocking the furin cleavage of viral class I fusion proteins. Here, we report a novel antiviral mechanism of MARCH1 and MARCH2 (MARCH1/2) in the replication of Pseudorabies virus (PRV), a member of the Herpesviridae family. We discovered MARCH1/2 restrict PRV replication at the cell-to-cell fusion step. Furthermore, MARCH1/2 block gB cleavage, and this is dependent on their E3 ligase activity. Interestingly, the blocking of gB cleavage by MARCH1/2 does not contribute to their antiviral activity in vitro. We discovered that MARCH1/2 are associated with the cell-to-cell fusion complex of gB, gD, gH, and gL and trap these viral proteins in the trans-Golgi network (TGN) rather than degrading them. Overall, we conclude that MARCH1/2 inhibit PRV by trapping the viral cell-to-cell fusion complex in TGN.

The spatial patterns of diversity and their relationships with environments in rhizosphere microorganisms and host plants differ along elevational gradients.

Introduction: Identifying spatial patterns of biodiversity along elevational gradients provides a unified framework for understanding these patterns and predicting ecological responses to climate change. Moreover, microorganisms and plants are closely interconnected (e.g., via the rhizosphere) and thus may share spatial patterns of diversity and show similar relationships with environments. Methods: This study compared diversity patterns and relationships with environments in host plants and rhizosphere microorganisms (including various functional groups) along elevational gradients across three climatic zones. Results: We found that above-and belowground diversity decreased monotonically or showed a hump-shaped or U-shaped pattern along elevation gradients. However, the diversity patterns of plants, bacteria, and fungi varied depending on the taxon and climatic zone. Temperature and humidity strongly contribute to above-and belowground diversity patterns and community composition along elevational gradients. Nonetheless, soil factors might be important regulators of diversity patterns and the community composition of plants and microorganisms along these gradients. Structural equation modeling revealed that environmental factors had a stronger direct effect on rhizosphere microbial diversity than host plant diversity. Discussion: In sum, spatial patterns of diversity and their relationships with environments in rhizosphere microorganisms and their host plants differed at the regional scale. Different functional groups (e.g., pathogen, mycorrhiza and nitrifier) of soil microorganisms may have divergent elevational patterns and environmental responses. These data improve our understanding of elevational diversity patterns, and provide new insights into the conservation of biodiversity and ecosystem management, especially under climate change.

lncRNA H19 Promotes Ox-LDL-Induced Dysfunction of Human Aortic Endothelial Cells through the miR-152/VEGFA Axis.

Objective: lncRNA H19 (H19) elevation is related to the risk of coronary artery disease. DIANA-lncBase database analysis suggested that microRNA-152 (miR-152) and H19 have binding sites. Here, the effect and mechanism of H19 and miR-152 in the oxidized low-density lipoprotein (ox-LDL)-induced human aortic endothelial cells (HAECs) were explored. Methods: The expression of H19, miR-152, and vascular endothelial growth factor (VEGF)-A in the HAECs treated with 5 µg/mL ox-LDL was detected by qRT-PCR. MTT, wound-healing assay, and tube formation assay were analyzed to evaluate the angiogenic activity of H19 and miR-152 in the HAECs cells knocked down H19. Dual-luciferase assay was performed to verify the targeting relationship of miR-152 to either H19 or VEGFA, respectively. Western blot was used to detect the expression of epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin and vimentin) and VEGFA protein in the cells. Results: After ox-LDL treatment, the expression of H19 and VEGFA was significantly increased, miR-152 expression was remarkably decreased. H19 was mainly expressed in the cytoplasm of HAECs. Knocking down H19 or overexpression of miR-152 significantly inhibited the cellular proliferation, migration, tube formation, and EMT trend of the HAECs. On the contrary, miR-152 interference reversed H19 silencing-mediated effects in the ox-LDL-induced HAECs. The dual-luciferase assay showed that miR-152 had a targeting relationship with H19 and VEGFA. MiR-152 was negatively corrected with the VEGFA expression. Conclusion: Ox-LDL negatively regulates miR-152 via H19, promotes the expression of VEGFA, and induces the dysfunction of HAECs.

[Detection and typing of caliciviruses from patients with acute diarrhea in Hangzhou area, 2009 - 2010].

OBJECTIVE: To investigate the molecular-epidemiologic characteristics and genotypes of human calicivirus (HuCVs) in acute diarrhea patients in Hangzhou from 2009 to 2010. METHODS: Epidemiologic data and fecal specimens were collected from patients with acute diarrhea. HuCVs of 920 specimens were detected by PCR. PCR products of several positive samples were randomly selected and sequenced. All the sequences were analyzed, phylogenetically. RESULTS: 201 HuCVs positive cases were identified from 920 facal specimens (21.8%). 25 isolates would include norovirus GI-type, GII-type for 170 strains and sapovirus for 11 strains. Norovirus GI-type and GII-type were detected in four specimens at the same time. Other specimens were mixed infection with norovirus GII-type and sapovirus. Genotypes of HuCVs showed that norovirus GI subtypes were GI-1 (3 strains) and GI-2 (1 strain). Norovirus GII subtypes were GII-4/2006b variant strains (7 strains), GII-2 (1 strain), GII-7 (1 strain) and GII-4/2008 variant strains (2 strains); Sapovirus subtypes were GI-2 (5 strains), GI-1 (4 strains) and GII-1 (1 strain). The prevalence rates of HuCVs were different in seasons and age groups. CONCLUSION: HuCVs were one of the major pathogens causing acute diarrhea. Both multiple viruses and genotypes of HuCVs were found in the specimens. GII-4/2006b variant and similar strains were identified, probably as the prevalent strains from 2009 to 2010 in Hangzhou, Zhejiang province.