Susceptibility gene identification and risk evaluation model construction by transcriptome-wide association analysis for salt sensitivity of blood pressure.

BACKGROUND: Salt sensitivity of blood pressure (SSBP) is an intermediate phenotype of hypertension and is a predictor of long-term cardiovascular events and death. However, the genetic structures of SSBP are uncertain, and it is difficult to precisely diagnose SSBP in population. So, we aimed to identify genes related to susceptibility to the SSBP, construct a risk evaluation model, and explore the potential functions of these genes. METHODS AND RESULTS: A genome-wide association study of the systemic epidemiology of salt sensitivity (EpiSS) cohort was performed to obtain summary statistics for SSBP. Then, we conducted a transcriptome-wide association study (TWAS) of 12 tissues using FUSION software to predict the genes associated with SSBP and verified the genes with an mRNA microarray. The potential roles of the genes were explored. Risk evaluation models of SSBP were constructed based on the serial P value thresholds of polygenetic risk scores (PRSs), polygenic transcriptome risk scores (PTRSs) and their combinations of the identified genes and genetic variants from the TWAS. The TWAS revealed that 2605 genes were significantly associated with SSBP. Among these genes, 69 were differentially expressed according to the microarray analysis. The functional analysis showed that the genes identified in the TWAS were enriched in metabolic process pathways. The PRSs were correlated with PTRSs in the heart atrial appendage, adrenal gland, EBV-transformed lymphocytes, pituitary, artery coronary, artery tibial and whole blood. Multiple logistic regression models revealed that a PRS of P < 0.05 had the best predictive ability compared with other PRSs and PTRSs. The combinations of PRSs and PTRSs did not significantly increase the prediction accuracy of SSBP in the training and validation datasets. CONCLUSIONS: Several known and novel susceptibility genes for SSBP were identified via multitissue TWAS analysis. The risk evaluation model constructed with the PRS of susceptibility genes showed better diagnostic performance than the transcript levels, which could be applied to screen for SSBP high-risk individuals.

Genomic Insights into Adaptation to Karst Limestone and Incipient Speciation in East Asian Platycarya spp. (Juglandaceae).

When challenged by similar environmental conditions, phylogenetically distant taxa often independently evolve similar traits (convergent evolution). Meanwhile, adaptation to extreme habitats might lead to divergence between taxa that are otherwise closely related. These processes have long existed in the conceptual sphere, yet molecular evidence, especially for woody perennials, is scarce. The karst endemic Platycarya longipes, and its only congeneric species, P. strobilacea, which is widely distributed in the mountains in East Asia, provide an ideal model for examining the molecular basis of both convergent evolution and speciation. Using chromosome-level genome assemblies of both species, and whole genome resequencing data from 207 individuals spanning their entire distribution range, we demonstrate that P. longipes and P. strobilacea form two species-specific clades, which diverged around 2.09 million years ago. We find an excess of genomic regions exhibiting extreme interspecific differentiation, potentially due to long-term selection in P. longipes, likely contributing to the incipient speciation of the genus Platycarya. Interestingly, our results unveil underlying karst adaptation in both copies of the calcium influx channel gene TPC1 in P. longipes. TPC1 has previously been identified as a selective target in certain karst-endemic herbs, indicating a convergent adaptation to high calcium stress among karst-endemic species. Our study reveals the genic convergence of TPC1 among karst endemics, and the driving forces underneath the incipient speciation of the two Platycarya lineages.

Genomic Insights into Adaptation to Karst Limestone and Incipient Speciation in East Asian Platycarya spp. (Juglandaceae).

When challenged by similar environmental conditions, phylogenetically distant taxa often independently evolve similar traits (convergent evolution). Meanwhile, adaptation to extreme habitats might lead to divergence between taxa that are otherwise closely related. These processes have long existed in the conceptual sphere, yet molecular evidence, especially for woody perennials, is scarce. The karst endemic Platycarya longipes and its only congeneric species, Platycarya strobilacea, which is widely distributed in the mountains in East Asia, provide an ideal model for examining the molecular basis of both convergent evolution and speciation. Using chromosome-level genome assemblies of both species, and whole-genome resequencing data from 207 individuals spanning their entire distribution range, we demonstrate that P. longipes and P. strobilacea form two species-specific clades, which diverged around 2.09 million years ago. We find an excess of genomic regions exhibiting extreme interspecific differentiation, potentially due to long-term selection in P. longipes, likely contributing to the incipient speciation of the genus Platycarya. Interestingly, our results unveil underlying karst adaptation in both copies of the calcium influx channel gene TPC1 in P. longipes. TPC1 has previously been identified as a selective target in certain karst-endemic herbs, indicating a convergent adaptation to high calcium stress among karst-endemic species. Our study reveals the genic convergence of TPC1 among karst endemics and the driving forces underneath the incipient speciation of the two Platycarya lineages.

CircNSD1 promotes cardiac fibrosis through targeting the miR-429-3p/SULF1/Wnt/ß-catenin signaling pathway.

Cardiac fibrosis is a detrimental pathological process, which constitutes the key factor for adverse cardiac structural remodeling leading to heart failure and other critical conditions. Circular RNAs (circRNAs) have emerged as important regulators of various cardiovascular diseases. It is known that several circRNAs regulate gene expression and pathological processes by binding miRNAs. In this study we investigated whether a novel circRNA, named circNSD1, and miR-429-3p formed an axis that controls cardiac fibrosis. We established a mouse model of myocardial infarction (MI) for in vivo studies and a cellular model of cardiac fibrogenesis in primary cultured mouse cardiac fibroblasts treated with TGF-ß1. We showed that miR-429-3p was markedly downregulated in the cardiac fibrosis models. Through gain- and loss-of-function studies we confirmed miR-429-3p as a negative regulator of cardiac fibrosis. In searching for the upstream regulator of miR-429-3p, we identified circNSD1 that we subsequently demonstrated as an endogenous sponge of miR-429-3p. In MI mice, knockdown of circNSD1 alleviated cardiac fibrosis. Moreover, silence of human circNSD1 suppressed the proliferation and collagen production in human cardiac fibroblasts in vitro. We revealed that circNSD1 directly bound miR-429-3p, thereby upregulating SULF1 expression and activating the Wnt/ß-catenin pathway. Collectively, circNSD1 may be a novel target for the treatment of cardiac fibrosis and associated cardiac disease.

Genomic insights into biased allele loss and increased gene numbers after genome duplication in autotetraploid Cyclocarya paliurus.

BACKGROUND: Autopolyploidy is a valuable model for studying whole-genome duplication (WGD) without hybridization, yet little is known about the genomic structural and functional changes that occur in autopolyploids after WGD. Cyclocarya paliurus (Juglandaceae) is a natural diploid-autotetraploid species. We generated an allele-aware autotetraploid genome, a chimeric chromosome-level diploid genome, and whole-genome resequencing data for 106 autotetraploid individuals at an average depth of 60 × per individual, along with 12 diploid individuals at an average depth of 90 × per individual. RESULTS: Autotetraploid C. paliurus had 64 chromosomes clustered into 16 homologous groups, and the majority of homologous chromosomes demonstrated similar chromosome length, gene numbers, and expression. The regions of synteny, structural variation and nonalignment to the diploid genome accounted for 81.3%, 8.8% and 9.9% of the autotetraploid genome, respectively. Our analyses identified 20,626 genes (69.18%) with four alleles and 9191 genes (30.82%) with one, two, or three alleles, suggesting post-polyploid allelic loss. Genes with allelic loss were found to occur more often in proximity to or within structural variations and exhibited a marked overlap with transposable elements. Additionally, such genes showed a reduced tendency to interact with other genes. We also found 102 genes with more than four copies in the autotetraploid genome, and their expression levels were significantly higher than their diploid counterparts. These genes were enriched in enzymes involved in stress response and plant defense, potentially contributing to the evolutionary success of autotetraploids. Our population genomic analyses suggested a single origin of autotetraploids and recent divergence (~ 0.57 Mya) from diploids, with minimal interploidy admixture. CONCLUSIONS: Our results indicate the potential for genomic and functional reorganization, which may contribute to evolutionary success in autotetraploid C. paliurus.

TGFßR-1/ALK5 inhibitor RepSox induces enteric glia-to-neuron transition and influences gastrointestinal mobility in adult mice.

Promoting adult neurogenesis in the enteric nervous system (ENS) may be a potential therapeutic approach to cure enteric neuropathies. Enteric glial cells (EGCs) are the most abundant glial cells in the ENS. Accumulating evidence suggests that EGCs can be a complementary source to supply new neurons during adult neurogenesis in the ENS. In the brain, astrocytes have been intensively studied for their neuronal conversion properties, and small molecules have been successfully used to induce the astrocyte-to-neuron transition. However, research on glia-to-neuron conversion in the ENS is still lacking. In this study, we used GFAP-Cre:Rosa-tdTomato mice to trace glia-to-neuron transdifferentiation in the ENS in vivo and in vitro. We showed that GFAP promoter-driven tdTomato exclusively labelled EGCs and was a suitable marker to trace EGCs and their progeny cells in the ENS of adult mice. Interestingly, we discovered that RepSox or other ALK5 inhibitors alone induced efficient transdifferentiation of EGCs into neurons in vitro. Knockdown of ALK5 further confirmed that the TGFßR-1/ALK5 signalling pathway played an essential role in the transition of EGCs to neurons. RepSox-induced neurons were Calbindin- and nNOS-positive and displayed typical neuronal electrophysiological properties. Finally, we showed that administration of RepSox (3, 10 mg· kg-1 ·d-1, i.g.) for 2 weeks significantly promoted the conversion of EGCs to neurons in the ENS and influenced gastrointestinal motility in adult mice. This study provides a method for efficiently converting adult mouse EGCs into neurons by small-molecule compounds, which might be a promising therapeutic strategy for gastrointestinal neuropathy.

Phase Transition Engineering of Host Perovskite toward Optimal Exsolution-facilitated Catalysts for Carbon Dioxide Electrolysis.

The in situ exsolution technique of nanoparticles has brought new opportunities for the utilization of perovskite-based catalysts in solid oxide cells. However, the lack of control over the structural evolution of host perovskites during the promotion of exsolution has restricted the architectural exploitation of exsolution-facilitated perovskites. In this study, we strategically broke the long-standing trade-off phenomenon between promoted exsolution and suppressed phase transition via B-site supplement, thus broadening the scope of exsolution-facilitated perovskite materials. Using carbon dioxide electrolysis as an illustrative case study, we demonstrate that the catalytic activity and stability of perovskites with exsolved nanoparticles (P-eNs) can be selectively enhanced by regulating the explicit phase of host perovskites, accentuating the critical role of the architectures of perovskite scaffold in catalytic reactions occurring on P-eNs. The concept demonstrated could potentially pave the way for designing the advanced exsolution-facilitated P-eNs materials and unveiling a wide range of catalytic chemistry taking place on P-eNs.

Synthesis of Conjugated Donor-Acceptor Antiaromatic Porphyrins and Their Application to Perovskite Solar Cells.

A conjugated donor-acceptor antiaromatic porphyrin, composed of an antiaromatic thieno-fused porphyrin structure and a diketopyrrolopyrrole mioety, was synthesized and applied in a perovskite solar cell for the first time. Enhanced light absorption in the device by the antiaromatic porphyrin resulted in a significantly increased power conversion efficiency of 19.3%.

Standing genetic variation as the predominant source for adaptation of a songbird.

What kind of genetic variation contributes the most to adaptation is a fundamental question in evolutionary biology. By resequencing genomes of 80 individuals, we inferred the origin of genomic variants associated with a complex adaptive syndrome involving multiple quantitative traits, namely, adaptation between high and low altitudes, in the vinous-throated parrotbill (Sinosuthora webbiana) in Taiwan. By comparing these variants with those in the Asian mainland population, we revealed standing variation in 24 noncoding genomic regions to be the predominant genetic source of adaptation. Parrotbills at both high and low altitudes exhibited signatures of recent selection, suggesting that not only the front but also the trailing edges of postglacial expanding populations could be subjected to environmental stresses. This study verifies and quantifies the importance of standing variation in adaptation in a cohort of genes, illustrating that the evolutionary potential of a population depends significantly on its preexisting genetic diversity. These findings provide important context for understanding adaptation and conservation of species in the Anthropocene.

The resistance of peanut to soil-borne pathogens improved by rhizosphere probiotics under calcium treatment.

BACKGROUND: Peanut (Arachis hypogaea L.) is an important oil and economic crop. Calcium modulates plants in response to abiotic stresses and improves plant resistance to pathogens. Enrichment of beneficial microorganisms in the rhizosphere is associated with plant disease resistance and soil development. The purpose of this study was to analyze the differences in peanut rhizosphere microbial community structure between the calcium treatment and the control during two growth stages and to explain why calcium application could improve the resistance of peanuts to soil-borne pathogens. RESULTS: The 16S rDNA amplicon sequencing of rhizosphere microbiome showed that calcium application significantly enriched Serratia marcescens and other three dominant strains at the seedling stage. At the pod filling stage, ten dominant stains such as Sphingomonas changbaiensis and Novosphingobium panipatense were enriched by calcium. Serratia marcescens aseptic fermentation filtrate was mixed with PDA medium and inoculated with the main soil-borne pathogens in the seedling stage, which could inhibit the growth of Fusarium solani and Aspergillus flavus. The aseptic fermentation filtrate of Novosphingobium panipatense was mixed with PDA medium and inoculated with the main soil-borne pathogens in the pod filling stage, which could inhibit the growth of Sclerotium rolfsii and Leptosphaerulina arachidicola. CONCLUSIONS: Calcium application increases the resistance of peanuts to soil-borne pathogens by enriching them with specific dominant bacteria.

Different rates of pollen and seed gene flow cause branch-length and geographic cytonuclear discordance within Asian butternuts.

Topological cytonuclear discordance is commonly observed in plant phylogenetic and phylogeographic studies, yet few studies have attempted to detect two other forms of cytonuclear discordance (branch length and geographical) and to uncover the causes of the discordance. We used the whole nuclear and chloroplast genome data from 80 individual Asian butternuts to reveal the pattern and processes of cytonuclear discordance. Our findings indicate that the chloroplast genome had substantially deeper divergence (branch-length discordance) and a steeper cline in the contact zone (geographic discordance) compared with the nuclear genome. After various hypothesis have been tested, the results suggest that incomplete lineage sorting, positive selection and cytonuclear incompatibility are probably insufficient to explain this pattern. However, isolation-by-distance analysis and gene flow estimation point to a much higher level of gene flow by pollen compared with by seeds, which may have slowed down lineage divergence and mediated wider contact for nuclear genome compared with the chloroplast genome. Altogether, this study highlights a critical role of sex-biased dispersal in causing discordance between the nuclear and plastid genome of Asian butternuts. Given its ubiquity among plants, asymmetric gene flow should be given a high priority in future studies of cytonuclear discordance.

Phylogenomics Reveals an Ancient Hybrid Origin of the Persian Walnut.

Persian walnut (Juglans regia) is cultivated worldwide for its high-quality wood and nuts, but its origin has remained mysterious because in phylogenies it occupies an unresolved position between American black walnuts and Asian butternuts. Equally unclear is the origin of the only American butternut, J. cinerea. We resequenced the whole genome of 80 individuals from 19 of the 22 species of Juglans and assembled the genome of its relatives Pterocarya stenoptera and Platycarya strobilacea. Using phylogenetic-network analysis of single-copy nuclear genes, genome-wide site pattern probabilities, and Approximate Bayesian Computation, we discovered that J. regia (and its landrace J. sigillata) arose as a hybrid between the American and the Asian lineages and that J. cinerea resulted from massive introgression from an immigrating Asian butternut into the genome of an American black walnut. Approximate Bayesian Computation modeling placed the hybrid origin in the late Pliocene, ∼3.45 My, with both parental lineages since having gone extinct in Europe.

Health assistant: answering your questions anytime from biomedical literature.

MOTIVATION: With the abundant medical resources, especially literature available online, it is possible for people to understand their own health status and relevant problems autonomously. However, how to obtain the most appropriate answer from the increasingly large-scale database, remains a great challenge. Here, we present a biomedical question answering framework and implement a system, Health Assistant, to enable the search process. METHODS: In Health Assistant, a search engine is firstly designed to rank biomedical documents based on contents. Then various query processing and search techniques are utilized to find the relevant documents. Afterwards, the titles and abstracts of top-N documents are extracted to generate candidate snippets. Finally, our own designed query processing and retrieval approaches for short text are applied to locate the relevant snippets to answer the questions. RESULTS: Our system is evaluated on the BioASQ benchmark datasets, and experimental results demonstrate the effectiveness and robustness of our system, compared to BioASQ participant systems and some state-of-the-art methods on both document retrieval and snippet retrieval tasks. AVAILABILITY AND IMPLEMENTATION: A demo of our system is available at https://github.com/jinzanxia/biomedical-QA.

Transcriptome and cell wall degrading enzyme-related gene analysis of Pestalotiopsis neglecta in response to sodium pheophorbide a.

Sodium pheophorbide a (SPA) is a new alternative fungicide with low toxicity and high efficiency, which has high fungicidal activity against Pestalotiopsis neglecta, a pathogen that causes black spot needle blight of Pinus sylvestris var. mongolica. To utilize SPA for plant disease control, understanding its antifungal mechanism is essential. Six cDNA libraries were constructed from 3 d-old P. neglecta mycelia (three SPA-infected and three untreated groups) and 29,850 expressed genes were obtained by Illumina HiSeq4000 sequencing. Compared with controls, 3268 differentially expressed genes (DEGs) were identified in SPA-treated groups, including 1879 upregulated and 1389 downregulated genes. Most DEGs were involved in the metabolism of amino acids, carbohydrates, and lipids, as well as cell structure and genetic information processing. These findings were further confirmed by decreased conductivity, RNA and protein content, and activities of nicotinamide adenine dinucleotide-dependent malate dehydrogenase, citrate synthase, isocitrate dehydrogenase, and succinate dehydrogenase. Moreover, qRT-PCR verified the reliability of the transcriptome results. After treatment with SPA at different concentrations for 60 min, the expressions of three cell wall degrading enzyme-related genes (PnEG, PnBG, and PnPG) were all suppressed. Overall, this study provided insights into the molecular mechanisms through which SPA inhibits P. neglecta, increasing the possibility of developing SPA into an effective fungicide in the future.

Sodium pheophorbide a controls cherry tomato gray mold (Botrytis cinerea) by destroying fungal cell structure and enhancing disease resistance-related enzyme activities in fruit.

Sodium pheophorbide a (SPA) is a natural photosensitizer. The present study investigated the antifungal activity and mechanism of SPA against Botrytis cinerea in vitro and in vivo. Its inhibitory effect was studied on the spore germination and mycelial growth of B. cinerea. The effects of SPA on cell wall integrity, cell membrane permeability, and mycelial morphology of B. cinerea were also determined. Additionally, how SPA effected B. cinerea in vivo was evaluated using cherry tomato fruit. The results showed that SPA effectively inhibited the spore germination and mycelial growth of B. cinerea under light conditions (4000 lx). SPA significantly affected both cell wall integrity and cell membrane permeability (P < .05). In addition, SEM analysis suggested that B. cinerea treated with SPA (12.134 mg/mL) showed abnormal mycelial morphology, including atrophy, collapse, flattening, and mycelial wall dissolution. In vivo tests showed that SPA could increase the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) significantly (P < .05); however, SPA had no significant effect on phenylalanine ammonia lyase (PAL) activity. In short, SPA could destroy the fungal cell structure and enhance disease resistance-related enzyme activity in cherry tomatoes, thereby controlling cherry tomato gray mold.

Key factors affecting photoactivated fungicidal activity of sodium pheophorbide a against Pestalotiopsis neglecta.

Recently, photodynamic therapy (PDT) and photoactivated pesticides have attracted considerable research attention. In the present study, we aimed to investigate the photodynamic activity of a chlorophyllous derivative, sodium pheophorbide a (SPA), and to evaluate its potential as a photoactivated fungicide. The singlet oxygen quantum yield, the photoreaction process, the anti-photobleaching ability in sterile water (H2O), the effect of light conditions on its antifungal activity, and its stability were all investigated. SPA showed significant fungicidal activity and photostability, during which Type I and Type II photodynamic reactions occurred simultaneously on Pestalotiopsis neglecta, and the influence of Type I was slightly larger than that of Type II. In addition, light promoted the antifungal activity of SPA. In particular, the antifungal activity was enhanced with increasing light intensity, and was strongest under 8000 lx conditions. Under monochromatic light sources, antifungal activity was strongest under green light s; however, the effect of monochromatic light was not as good as that of white light. From 0 to 24 h, the antifungal effect of the SPA solution was enhanced; however, the activity of the solution began to weaken after 24 h. Furthermore, our study confirmed that the antifungal activity of SPA was stable under different temperatures, pH values, and UV irradiation durations.

Epidemiologic relationship between periodontitis and type 2 diabetes mellitus.

BACKGROUND: To systematically review the epidemiologic relationship between periodontitis and type 2 diabetes mellitus (T2DM). METHODS: Four electronic databases were searched up until December 2018. The manual search included the reference lists of the included studies and relevant journals. Observational studies evaluating the relationship between T2DM and periodontitis were included. Meta-analyses were conducted using STATA. RESULTS: A total of 53 observational studies were included. The Adjusted T2DM prevalence was significantly higher in periodontitis patients (OR = 4.04, p = 0.000), and vice versa (OR = 1.58, p = 0.000). T2DM patients had significantly worse periodontal status, as reflected in a 0.61 mm deeper periodontal pocket, a 0.89 mm higher attachment loss and approximately 2 more lost teeth (all p = 0.000), than those without T2DM. The results of the cohort studies found that T2DM could elevate the risk of developing periodontitis by 34% (p = 0.002). The glycemic control of T2DM patients might result in different periodontitis outcomes. Severe periodontitis increased the incidence of T2DM by 53% (p = 0.000), and this result was stable. In contrast, the impact of mild periodontitis on T2DM incidence (RR = 1.28, p = 0.007) was less robust. CONCLUSIONS: There is an evident bidirectional relationship between T2DM and periodontitis. Further well-designed cohort studies are needed to confirm this finding. Our results suggest that both dentists and physicians need to be aware of the strong connection between periodontitis and T2DM. Controlling these two diseases might help prevent each other's incidence.

Aerobic prokaryotes do not have higher GC contents than anaerobic prokaryotes, but obligate aerobic prokaryotes have.

BACKGROUND: Among the four bases, guanine is the most susceptible to damage from oxidative stress. Replication of DNA containing damaged guanines results in G to T mutations. Therefore, the mutations resulting from oxidative DNA damage are generally expected to predominantly consist of G to T (and C to A when the damaged guanine is not in the reference strand) and result in decreased GC content. However, the opposite pattern was reported 16 years ago in a study of prokaryotic genomes. Although that result has been widely cited and confirmed by nine later studies with similar methods, the omission of the effect of shared ancestry requires a re-examination of the reliability of the results. RESULTS: When aerobic and obligate aerobic prokaryotes were mixed together and anaerobic and obligate anaerobic prokaryotes were mixed together, phylogenetic controlled analyses did not detect significant difference in GC content between aerobic and anaerobic prokaryotes. This result is consistent with two generally neglected studied that had accounted for the phylogenetic relationship. However, when obligate aerobic prokaryotes were compared with aerobic prokaryotes, anaerobic prokaryotes, and obligate anaerobic prokaryotes separately using phylogenetic regression analysis, a significant positive association was observed between aerobiosis and GC content, no matter it was calculated from whole genome sequences or the 4-fold degenerate sites of protein-coding genes. Obligate aerobes have significantly higher GC content than aerobes, anaerobes, and obligate anaerobes. CONCLUSIONS: The positive association between aerobiosis and GC content could be attributed to a mutational force resulting from incorporation of damaged deoxyguanosine during DNA replication rather than oxidation of the guanine nucleotides within DNA sequences. Our results indicate a grade in the aerobiosis-associated mutational force, strong in obligate aerobes, moderate in aerobes, weak in anaerobes and obligate anaerobes.

Circular RNAs in human and vertebrate neural retinas.

Circular RNAs (circRNAs) belong to an endogenous class of RNA molecules with both ends covalently linked in a circle. Although their expression pattern in the mammalian brain has been well studied, the characteristics and functions of circRNAs in retinas remain unknown. To reveal the whole expression profiles of circRNAs in the neural retina, we investigated retinal RNAs of human, monkey, mouse, pig, zebrafish and tree shrew and detected thousands of circRNAs showing conservation and variation in the retinas across different vertebrate species. We further investigated one of the abundant circRNAs, circPDE4B, identified in human retina. Silencing of circPDE4B significantly inhibited the proliferation of human A549 cells. Functional assays demonstrated that circPDE4B could sponge miR-181C, thereby altering the cell phenotype. We have explored the retinal circRNA repertoires across human and different vertebrates, which provide new insights into the important role of circRNAs in the vertebrate retinas, as well as in related human diseases.

Functional characterization of 21 CYP3A4 variants on amiodarone metabolism in vitro.

1. Cytochrome P450 3A4 (CYP3A4) is an important member of the cytochrome P450 enzyme superfamily, with 33 allelic variants reported previously. Genetic polymorphisms of CYP3A4 can produce a significant effect on the efficacy and safety of some drugs, so the purpose of this study was to clarify the catalytic characteristics of 22 CYP3A4 allelic isoforms, including 6 novel variants in Han Chinese population, on the oxidative metabolism of amiodarone in vitro. 2. Wild-type CYP3A4*1 and other variants expressed by insect cells system were incubated respectively with 10-500 µM substrate for 40 min at 37 °C and terminated at -80 °C immediately. Then these samples were treated as required and detected with ultra-performance liquid chromatography-tandem mass spectrometry used to analyze its major metabolite desethylamiodarone. 3. Among the 21 CYP3A4 variants, compared with the wild-type, the intrinsic clearance values (Vmax/Km) of two variants were apparently decreased (11.07 and 2.67% relative clearance) while twelve variants revealed markedly increased values (155.20∼435.96%), and the remaining of seven variants exhibited no significant changes in enzyme activity. 4. This is the first time report describing all these infrequent alleles for amiodarone metabolism, which can provide fundamental data for further clinical studies on CYP3A4 alleles.