Global Standard Stratotype-Section and Point (GSSP) for the conterminous base of the Miaolingian Series and Wuliuan Stage (Cambrian) at Balang, Jianhe, Guizhou, China

The International Commission on Stratigraphy and the IUGS Executive Committee have recently ratified a Global Standard Stratotype-section and Point (GSSP) defining the conterminous base of the third series and the fifth stage of the Cambrian System. The series and the stage are respectively named the Miaolingian Series and Wuliuan Stage, after the Maioling Mountains in southeastern Guizhou and the Wuliu sidehill, Jianhe County, in eastern Guizhou Province, South China, where the GSSP is located. The GSSP is exposed in a natural outcrop near the Balang Village at a position of 26° 44.843′N latitude and 108° 24.830′E longitude. It is defined at the base of a silty mudstone layer 52.8 m above the base of the Kaili Formation in the Wuliu-Zengjiayan section, coinciding with the first appearance of the cosmopolitan oryctocephalid trilobite Oryctocephalus indicus (base of the O. indicus Zone). Secondary global markers at or near the base of the series and stage include the peak of a rather large negative carbon isotopic excursion (ROECE excursion), the simultaneous appearance of many acanthomorphic acritarch forms, a transgressive phase of a major eustatic event, and the last appearance of intercontinental polymerid trilobites, either Bathynotus or Ovatoryctocara. Faunal turnovers close to the base of the Miaolingian Series and Wuliuan Stage have been recognized as being at the base of the Oryctocephalus indicus Zone of Amgan Stage in Siberia, the Delamaran Stage in Laurentia, the Oryctocephalus indicus Zone in the Indian Himalaya and North Greenland, near the base of the Delamaran Stage in Australia, and within the Eccaparadocides sdzuyi Zone in Iberia and the Ornamentaspis frequens Zone in Morocco

A Young Drosophila Duplicate Gene Plays Essential Roles in Spermatogenesis by Regulating Several Y-Linked Male Fertility Genes

Gene duplication is supposed to be the major source for genetic innovations. However, how a new duplicate gene acquires functions by integrating into a pathway and results in adaptively important phenotypes has remained largely unknown. Here, we investigated the biological roles and the underlying molecular mechanism of the young kep1 gene family in the Drosophila melanogaster species subgroup to understand the origin and evolution of new genes with new functions. Sequence and expression analysis demonstrates that one of the new duplicates, nsr (novel spermatogenesis regulator), exhibits positive selection signals and novel subcellular localization pattern. Targeted mutagenesis and whole-transcriptome sequencing analysis provide evidence that nsr is required for male reproduction associated with sperm individualization, coiling, and structural integrity of the sperm axoneme via regulation of several Y chromosome fertility genes post-transcriptionally. The absence of nsr-like expression pattern and the presence of the corresponding cis-regulatory elements of the parental gene kep1 in the pre-duplication species Drosophila yakuba indicate that kep1 might not be ancestrally required for male functions and that nsr possibly has experienced the neofunctionalization process, facilitated by changes of trans-regulatory repertories. These findings not only present a comprehensive picture about the evolution of a new duplicate gene but also show that recently originated duplicate genes can acquire multiple biological roles and establish novel functional pathways by regulating essential genes

Genome-Wide Analysis of DNA Methylation and Cigarette Smoking in a Chinese Population

Background: Smoking is a risk factor for many human diseases. DNA methylation has been related to smoking, but genome-wide methylation data for smoking in Chinese populations is limited. Objectives: We aimed to investigate epigenome-wide methylation in relation to smoking in a Chinese population. Methods: We measured the methylation levels at > 485,000 CpG sites (CpGs) in DNA from leukocytes using a methylation array and conducted a genome-wide meta-analysis of DNA methylation and smoking in a total of 596 Chinese participants. We further evaluated the associations of smoking-related CpGs with internal polycyclic aromatic hydrocarbon (PAH) biomarkers and their correlations with the expression of corresponding genes. Results: We identified 318 CpGs whose methylation levels were associated with smoking at a genome-wide significance level (false discovery rate < 0.05), among which 161 CpGs annotated to 123 genes were not associated with smoking in recent studies of Europeans and African Americans. Of these smoking-related CpGs, methylation levels at 80 CpGs showed significant correlations with the expression of corresponding genes (including RUNX3, IL6R, PTAFR, ANKRD11, CEP135 and CDH23), and methylation at 15 CpGs was significantly associated with urinary 2-hydroxynaphthalene, the most representative internal monohydroxy-PAH biomarker for smoking. Conclusion: We identified DNA methylation markers associated with smoking in a Chinese population, including some markers that were also correlated with gene expression. Exposure to naphthalene, a byproduct of tobacco smoke, may contribute to smoking-related methylation. Citation: Zhu X, Li J, Deng S, Yu K, Liu X, Deng Q, Sun H, Zhang X, He M, Guo H, Chen W, Yuan J, Zhang B, Kuang D, He X, Bai Y, Han X, Liu B, Li X, Yang L, Jiang H, Zhang Y, Hu J, Cheng L, Luo X, Mei W, Zhou Z, Sun S, Zhang L, Liu C, Guo Y, Zhang Z, Hu FB, Liang L, Wu T. 2016. Genome-wide analysis of DNA methylation and cigarette smoking in Chinese. Environ Health Perspect 124:966–973; http://dx.doi.org/10.1289/ehp.150983

Gpr124 is essential for blood-brain barrier integrity in central nervous system disease

Although blood-brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt-β-catenin signaling. Constitutive activation of Wnt-β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption

Long-Term Thinning Does not Significantly Affect Soil Water-Stable Aggregates and Diversity of Bacteria and Fungi in Chinese Fir (<i>Cunninghamia lanceolata</i>) Plantations in Eastern China

Soil structure and microbial communities are sensitive to forest disturbance. However, little is known about the long-term effects of forest thinning on water-stable aggregates (WSA), and the community composition and diversity of soil microorganisms. In this study, we investigated soil chemical properties, WSA, and communities of bacteria and fungi in conventionally managed Chinese fir plantation stands and repeatedly thinned plantation stands with medium and high tree densities 18 years after the thinning treatments. The distribution patterns of WSA fractions were similar in the three thinning treatments. The mass proportion was the highest in the macro-aggregates fraction, followed by the clay + silt fraction, and it was the lowest in the micro-aggregates fraction. The soil organic carbon (SOC) concentrations in different WSA fractions decreased with decreasing aggregate size. The WSA fractions, stability, and aggregate-associated carbon were not significantly different among the three treatments 18 years after the thinning treatments. The total nitrogen concentration of the macro-aggregates fraction was significantly higher in the stands thinned intensively than in the conventionally managed stands. The abundance of minor bacteria and fungi species was different, although no significant differences were observed in the overall bacterial and fungal composition and diversity between the three treatments. Our results indicate that, compared with the conventionally managed stands, soil WSA stability and soil microbial communities in repeatedly thinned Chinese fir stands may recover over one rotation of Chinese fir plantation and that this is accompanied by the recovery of stand growth and soil nutrition

Which factors affect the performance of technology business incubators in China? An entrepreneurial ecosystem perspective

To examine which factors affect the performance of technology business incubators in China, the present study proposes an entrepreneurial ecosystem framework with four key areas, i.e., people, technology, capital, and infrastructure. We then assess this framework using a three-year panel data set of 857 national-level technology business incubators in 33 major cities from 28 provinces in China, from 2015 to 2017. We utilize factor analysis to downsize dozens of characteristics of these technology business incubators into seven factors related to the four proposed areas. Panel regression model results show that four of the seven factors related to three areas of the entrepreneurial ecosystem, namely people, technology, and capital areas, have statistically significant associations with an incubator’s performance when applied to the overall national data set. Further, seven factors related to all four areas have various statistically significant associations with an incubator’s performance in five major regional data set. In particular, a technology related factor has a consistently statistically significant association with the performance of the incubator in both national model and the five regional models, as we expected.</jats:p

Which factors affect the performance of technology business incubators in China? An entrepreneurial ecosystem perspective

To examine which factors affect the performance of technology business incubators in China, the present study proposes an entrepreneurial ecosystem framework with four key areas, i.e., people, technology, capital, and infrastructure. We then assess this framework using a three-year panel data set of 857 national-level technology business incubators in 33 major cities from 28 provinces in China, from 2015 to 2017. We utilize factor analysis to downsize dozens of characteristics of these technology business incubators into seven factors related to the four proposed areas. Panel regression model results show that four of the seven factors related to three areas of the entrepreneurial ecosystem, namely people, technology, and capital areas, have statistically significant associations with an incubator’s performance when applied to the overall national data set. Further, seven factors related to all four areas have various statistically significant associations with an incubator’s performance in five major regional data set. In particular, a technology related factor has a consistently statistically significant association with the performance of the incubator in both national model and the five regional models, as we expected

How microbial belowground communities cope with contrasted trophic resources across three land use type: a stoichiometry approach

National audienceLitters are the main trophic resources for soil microorganisms and play a key role in soil nutrient recycling. The amount of inorganic nutrients released into the ecosystem depends on the relative carbon (C) to nutrient (nitrogen and phosphorus, i.e. N and P) demand of the microorganisms, as well as the chemical composition of litters. The aim of this study was to determine how soil microbes regulate their C/N/P homeostasis to adapt to different litter resources and how this in turn affects the dynamics of organic matter. The hypothesis were a) litter mass losses are greater in “natural lands” because of wider functional dissimilarity and b) variation in soil microbial C/N/P ratio during the decomposition process reflects the difference of litter quality and is mainly caused by the shifts of community structure and function (enzyme excretion). In order to characterize the stoichiometric C/N/P ratio dynamics in added litters and soil microbial communities and the interaction between them, an in situ litter bag experiment was established using a reciprocal transplant design at the Mauguio INRA experimental station (Southern France). To explore the functional dissimilarity of soil microorganisms in different land use plots, a gradient going from little disturbed to highly disturbed soils was used. Low disturbed soil corresponded to a 25-year old walnut and black locust plantation with no fertilization and pesticides since its establishment. The second land use was an agricultural plot with organic practices since 2009 while the third land use corresponded to a plot with the same soil type but with conventional practices. Three different litters (wheat straw, pea and walnut leaves) were buried at 8cm depth into the three land use plots. Changes in litter quality, C/N/P ratio of the microbial biomass and of enzymes, DOC, mineral N and available P were monitored at different stages of decomposition

Litter quality impacts the CNP stoichiometric homeostasis of the soil microbial biomass

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