32 research outputs found

    Refining models of archaic admixture in Eurasia with ArchaicSeeker 2.0

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    We developed a method, ArchaicSeeker 2.0, to identify introgressed hominin sequences and model multiple-wave admixture. The new method enabled us to discern two waves of introgression from both Denisovan-like and Neanderthal-like hominins in present-day Eurasian populations and an ancient Siberian individual. We estimated that an early Denisovan-like introgression occurred in Eurasia around 118.8–94.0 thousand years ago (kya). In contrast, we detected only one single episode of Denisovan-like admixture in indigenous peoples eastern to the Wallace-Line. Modeling ancient admixtures suggested an early dispersal of modern humans throughout Asia before the Toba volcanic super-eruption 74 kya, predating the initial peopling of Asia as proposed by the traditional Out-of-Africa model. Survived archaic sequences are involved in various phenotypes including immune and body mass (e.g., ZNF169), cardiovascular and lung function (e.g., HHAT), UV response and carbohydrate metabolism (e.g., HYAL1/HYAL2/HYAL3), while “archaic deserts” are enriched with genes associated with skin development and keratinization

    Comparative genetic architectures of schizophrenia in East Asian and European populations

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    Schizophrenia is a debilitating psychiatric disorder with approximately 1% lifetime risk globally. Large-scale schizophrenia genetic studies have reported primarily on European ancestry samples, potentially missing important biological insights. Here, we report the largest study to date of East Asian participants (22,778 schizophrenia cases and 35,362 controls), identifying 21 genome-wide-significant associations in 19 genetic loci. Common genetic variants that confer risk for schizophrenia have highly similar effects between East Asian and European ancestries (genetic correlation = 0.98 ± 0.03), indicating that the genetic basis of schizophrenia and its biology are broadly shared across populations. A fixed-effect meta-analysis including individuals from East Asian and European ancestries identified 208 significant associations in 176 genetic loci (53 novel). Trans-ancestry fine-mapping reduced the sets of candidate causal variants in 44 loci. Polygenic risk scores had reduced performance when transferred across ancestries, highlighting the importance of including sufficient samples of major ancestral groups to ensure their generalizability across populations

    Understanding Users’ Willingness to Pay for Privacy in Mobile Applications: An Integration of Protection Motivation and Privacy Calculus

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    Recently, a new pattern of privacy protection, namely, paid privacy-enhancing services, has been regarded as a potential solution to current privacy issues. However, existing research on this new pattern is insufficient because of inconsistent findings on users’ willingness to pay (WTP) and the ambiguous underlying mechanism. Accordingly, integrating the theoretical lenses of protection motivation and privacy calculus and considering privacy literacy, this study proposes a framework to explain users’ behaviors towards paid privacy-enhancing services. Through online questionnaire surveys conducted in the contexts of apps with different levels of privacy sensitivity, the proposed framework is demonstrated to have great explanation and generalizability for users’ WTP. Our study offers insight into prior inconsistent findings and enriches the literature regarding privacy protection, consumers’ privacy behaviors, and privacy literacy. Our findings also demonstrate a potential way to balance consumers’ privacy concerns and companies’ various privacy appeals, providing significant implications for consumers, firms, and policymakers

    Identification and application of a growth-regulated promoter for improving l-valine production in Corynebacterium glutamicum

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    Abstract Background Promoters are commonly used to regulate the expression of specific target genes or operons. Although a series of promoters have been developed in Corynebacterium glutamicum, more precise and unique expression patterns are needed that the current selection of promoters cannot produce. RNA-Seq technology is a powerful tool for helping us to screen out promoters with expected transcriptional strengths. Results The promoter PCP_2836 of an aldehyde dehydrogenase coding gene from Corynebacterium glutamicum CP was identified via RNA-seq and RT-PCR as a growth-regulated promoter. Comparing with the strong constitutive promoter Ptuf, the transcriptional strength of PCP_2836 showed a significant decrease that from about 75 to 8% in the stationary phase. By replacing the native promoters of the aceE and gltA genes with PCP_2836 in the C. glutamicum ATCC 13032-derived l-valine-producing strain AN02, the relative transcriptional levels of the aceE and gltA genes decreased from 1.2 and 1.1 to 0.35 and 0.3, and the activity of their translation products decreased to 43% and 35%, respectively. After 28 h flask fermentation, the final cell density of the obtained strains, GRaceE and GRgltA, exhibited a 7–10% decrease. However, l-valine production increased by 23.9% and 27.3%, and the yield of substrate to product increased 43.8% and 62.5%, respectively. In addition, in the stationary phase, the intracellular citrate levels in GRaceE and GRgltA decreased to 27.0% and 33.6% of AN02, and their intracellular oxaloacetate levels increased to 2.7 and 3.0 times that of AN02, respectively. Conclusions The PCP_2836 promoter displayed a significant difference on its transcriptional strength in different cell growth phases. With using PCP_2836 to replace the native promoters of aceE and gltA genes, both the transcriptional levels of the aceE and gltA genes and the activity of their translation products demonstrated a significant decrease in the stationary phase. Thus, the availability of pyruvate was significantly increased for the synthesis of l-valine without any apparent irreversible negative impacts on cell growth. Use of this promoter can enhance the selectivity and control of gene expression and could serve as a useful research tool for metabolic engineering

    Comparison of Genetic Variants in Cancer-Related Genes between Chinese Hui and Han Populations.

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    The Chinese Hui population, as the second largest minority ethnic group in China, may have a different genetic background from Han people because of its unique demographic history. In this study, we aimed to identify genetic differences between Han and Hui Chinese from the Ningxia region of China by comparing eighteen single nucleotide polymorphisms in cancer-related genes.DNA samples were collected from 99 Hui and 145 Han people from the Ningxia Hui Autonomous Region in China, and SNPs were detected using an improved multiplex ligase detection reaction method. Genotyping data from six 1000 Genomes Project population samples (99 Utah residents with northern and western European ancestry (CEU), 107 Toscani in Italy (TSI), 108 Yoruba in Ibadan (YRI), 61 of African ancestry in the southwestern US (ASW), 103 Han Chinese in Beijing (CHB), and 104 Japanese in Tokyo (JPT)) were also included in this study. Differences in the distribution of alleles among the populations were assessed using χ2 tests, and FST was used to measure the degree of population differentiation.We found that the genetic diversity of many SNPs in cancer-related genes in the Hui Chinese in Ningxia was different from that in the Han Chinese in Ningxia. For example, the allele frequencies of four SNPs (rs13361707, rs2274223, rs465498, and rs753955) showed different genetic distributions (p0.000) between the Hui and Han populations.These results suggest that some SNPs associated with cancer-related genes vary among different Chinese ethnic groups. We suggest that population differences should be carefully considered in evaluating cancer risk and prognosis as well as the efficacy of cancer therapy

    Systems metabolic engineering strategies for the production of amino acids

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    Systems metabolic engineering is a multidisciplinary area that integrates systems biology, synthetic biology and evolutionary engineering. It is an efficient approach for strain improvement and process optimization, and has been successfully applied in the microbial production of various chemicals including amino acids. In this review, systems metabolic engineering strategies including pathway-focused approaches, systems biology-based approaches, evolutionary approaches and their applications in two major amino acid producing microorganisms: Corynebacterium glutamicum and Escherichia coli, are summarized

    Robust Spontaneous Raman Flow Cytometry for Single‐Cell Metabolic Phenome Profiling via pDEP‐DLD‐RFC

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    Abstract A full‐spectrum spontaneous single‐cell Raman spectrum (fs‐SCRS) captures the metabolic phenome for a given cellular state of the cell in a label‐free, landscape‐like manner. Herein a positive dielectrophoresis induced deterministic lateral displacement‐based Raman flow cytometry (pDEP‐DLD‐RFC) is established. This robust flow cytometry platform utilizes a periodical positive dielectrophoresis induced deterministic lateral displacement (pDEP‐DLD) force that is exerted to focus and trap fast‐moving single cells in a wide channel, which enables efficient fs‐SCRS acquisition and extended stable running time. It automatically produces deeply sampled, heterogeneity‐resolved, and highly reproducible ramanomes for isogenic cell populations of yeast, microalgae, bacteria, and human cancers, which support biosynthetic process dissection, antimicrobial susceptibility profiling, and cell‐type classification. Moreover, when coupled with intra‐ramanome correlation analysis, it reveals state‐ and cell‐type‐specific metabolic heterogeneity and metabolite‐conversion networks. The throughput of ≈30–2700 events min−1 for profiling both nonresonance and resonance marker bands in a fs‐SCRS, plus the >5 h stable running time, represent the highest performance among reported spontaneous Raman flow cytometry (RFC) systems. Therefore, pDEP‐DLD‐RFC is a valuable new tool for label‐free, noninvasive, and high‐throughput profiling of single‐cell metabolic phenomes
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