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Gene annotation is essential for genome-based studies. However, algorithm-based genome annotation is difficult to fully and correctly reveal genomic information, especially for species with complex genomes. Artemisia annua L. is the only commercial resource of artemisinin production though the content of artemisinin is still to be improved. Genome-based genetic modification and breeding are useful strategies to boost artemisinin content and therefore, ensure the supply of artemisinin and reduce costs, but better gene annotation is urgently needed. In this study, we manually corrected the newly released genome annotation of A. annua using second- and third-generation transcriptome data. We found that incorrect gene information may lead to differences in structural, functional, and expression levels compared to the original expectations. We also identified alternative splicing events and found that genome annotation information impacted identifying alternative splicing genes. We further demonstrated that genome annotation information and alternative splicing could affect gene expression estimation and gene function prediction. Finally, we provided a valuable version of A. annua genome annotation and demonstrated the importance of gene annotation in future research.
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Artemisia annua , Artemisininas , Artemisia annua/genética , Empalme Alternativo/genética , Fitomejoramiento , GenómicaRESUMEN
Andrographis paniculata is a herbaceous dicot plant widely used for its anti-inflammatory and anti-viral properties across its distribution in China, India and other Southeast Asian countries. A. paniculata was used as a crucial therapeutic treatment during the influenza epidemic of 1919 in India, and is still used for the treatment of infectious disease in China. A. paniculata produces large quantities of the anti-inflammatory diterpenoid lactones andrographolide and neoandrographolide, and their analogs, which are touted to be the next generation of natural anti-inflammatory medicines for lung diseases, hepatitis, neurodegenerative disorders, autoimmune disorders and inflammatory skin diseases. Here, we report a chromosome-scale A. paniculata genome sequence of 269 Mb that was assembled by Illumina short reads, PacBio long reads and high-confidence (Hi-C) data. Gene annotation predicted 25 428 protein-coding genes. In order to decipher the genetic underpinning of diterpenoid biosynthesis, transcriptome data from seedlings elicited with methyl jasmonate were also obtained, which enabled the identification of genes encoding diterpenoid synthases, cytochrome P450 monooxygenases, 2-oxoglutarate-dependent dioxygenases and UDP-dependent glycosyltransferases potentially involved in diterpenoid lactone biosynthesis. We further carried out functional characterization of pairs of class-I and -II diterpene synthases, revealing the ability to produce diversified labdane-related diterpene scaffolds. In addition, a glycosyltransferase able to catalyze O-linked glucosylation of andrograpanin, yielding the major active product neoandrographolide, was also identified. Thus, our results demonstrate the utility of the combined genomic and transcriptomic data set generated here for the investigation of the production of the bioactive diterpenoid lactone constituents of the important medicinal herb A. paniculata.
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Andrographis/genética , Diterpenos/metabolismo , Genoma de Planta/genética , Glucósidos/biosíntesis , Fitoquímicos/biosíntesis , Proteínas de Plantas/metabolismo , Andrographis/química , Andrographis/enzimología , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Proteínas de Plantas/genética , Plantas Medicinales/química , Plantas Medicinales/enzimología , Plantas Medicinales/genética , TetrahidronaftalenosRESUMEN
The sacred lotus (Nelumbo nucifera) is widely cultured in East Asia for its horticultural, agricultural, and medicinal values. Although many molecular markers had been used to extrapolate population genetics of the sacred lotus, a study of large variations, such as copy number variation (CNV), are absent up to now. In this study, we applied whole-genome re-sequencing to 24 lotus accessions, and use read depth information to genotype and filter original CNV call. Totally 448 duplications and 4,267 deletions were identified in the final CNV set. Further analysis of population structure revealed that the population structure patterns revealed by CNV and SNP are largely consistent with each other. Our result indicated that deep sequencing followed by genotyping is a quick and straightforward way to mine out CNV from the population, and the CNV along with SNP could enable us to better comprehend the biology of the plant.
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Variaciones en el Número de Copia de ADN/genética , Nelumbo/genética , Polimorfismo de Nucleótido SimpleRESUMEN
In a broad range of taxa, genes can duplicate through an RNA intermediate in a process mediated by retrotransposons (retroposition). In mammals, L1 retrotransposons drive retroposition, but the elements responsible for retroposition in other animals have yet to be identified. Here, we examined young retrocopies from various animals that still retain the sequence features indicative of the underlying retroposition mechanism. In Drosophila melanogaster, we identified and de novo assembled 15 polymorphic retrocopies and found that all retroposed loci are chimeras of internal retrocopies flanked by discontinuous LTR retrotransposons. At the fusion points between the mRNAs and the LTR retrotransposons, we identified shared short similar sequences that suggest the involvement of microsimilarity-dependent template switches. By expanding our approach to mosquito, zebrafish, chicken, and mammals, we identified in all these species recently originated retrocopies with a similar chimeric structure and shared microsimilarities at the fusion points. We also identified several retrocopies that combine the sequences of two or more parental genes, demonstrating LTR-retroposition as a novel mechanism of exon shuffling. Finally, we found that LTR-mediated retrocopies are immediately cotranscribed with their flanking LTR retrotransposons. Transcriptional profiling coupled with sequence analyses revealed that the sense-strand transcription of the retrocopies often lead to the origination of in-frame proteins relative to the parental genes. Overall, our data show that LTR-mediated retroposition is highly conserved across a wide range of animal taxa; combined with previous work from plants and yeast, it represents an ancient and ongoing mechanism continuously shaping gene content evolution in eukaryotes.
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Duplicación de Gen , Perfilación de la Expresión Génica/métodos , ARN Mensajero/genética , Secuencias Repetidas Terminales , Animales , Pollos/genética , Culicidae/genética , Drosophila melanogaster/genética , Evolución Molecular , Humanos , Mamíferos/genética , Ratones , Retroelementos , Duplicaciones Segmentarias en el Genoma , Pez Cebra/genéticaRESUMEN
As an important component of the tumor microenvironment, CD4+ CD25+ Tregs reduce antitumor immunity, promote angiogenesis and metastasis in breast cancer. However, their function in regulating the "stemness" of tumor cells and the communication between Tregs and cancer stem cells (CSCs) remain elusive. Here, we disclose that the primarily cultured Tregs isolated from breast-tumor-bearing Foxp3-EGFP mouse upregulate the stemness property of breast cancer cells. Tregs increased the side-population and the Aldehyde dehydrogenase-bright population of mouse breast cancer cells, promoted their sphere formation in a paracrine manner, and enhanced the expression of stemness genes, such as Sox2 and so forth. In addition, Tregs increased tumorigenesis, metastasis, and chemoresistance of breast cancer cells. Furthermore, Sox2-overexpression tumor cells activated NF-κB-CCL1 signaling to recruit Tregs through reducing the binding of H3K27Me3 on promoter regions of p65 and Ccl1. These findings reveal the functional interaction between Tregs and CSCs and indicate that targeting on the communication between them is a promising strategy in breast cancer therapy. Stem Cells 2017;35:2351-2365.
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Quimiocina CCL1/metabolismo , Células Madre Neoplásicas/metabolismo , Factores de Transcripción SOXB1/metabolismo , Linfocitos T Reguladores/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Ratones , Factores de Transcripción SOXB1/genética , Transducción de Señal/genética , Transducción de Señal/fisiologíaRESUMEN
Soy isoflavone has benefits for metabolic syndrome but the mechanism is not completely understood. This study was designed to determine the effects of soy isoflavone on hepatic fat accumulation in non-alcoholic fatty liver disease (NAFLD) rats induced by high fat diet (HFD). Sprague-Dawley rats were administrated with a normal fat diet (control), HFD (NAFLD model), HFD with 10 or 20 mg/kg soy isoflavone daily for 12 weeks. Hepatic and serum lipid contents, liver histopathological examination, serum alanine transaminase (ALT), protein and mRNA expression of sterol regulatory element binding protein (SREBP)-1c, fatty acid synthase (FAS), peroxisome proliferator-activated receptor (PPAR) α were assayed respectively. Our study found that soy isoflavone reduced HFD-induced lipid accumulation in liver, serum ALT and improved liver lobule structure. In addition, the expression of SREBP-1c and FAS was lower, whereas protein level of PPARα was higher in two soy isoflavone groups than that of the HFD group. Collectively, these results demonstrate that soy isoflavone is capable of alleviating hepatic steatosis and delaying the progression of NAFLD via inhibiting lipogenesis and promoting fatty acid oxidation in liver.
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Temozolomide (TMZ) is widely used in the treatment of glioblastoma multiforme (GBM) as it can effectively inhibit the growth of GBM for some months; however, this cancer type is still incurable. The existence of glioma stem cells (GSCs) is thought to be responsible for the invariable recurrence of GBM after treatment, but GSCs are insensitive to TMZ. Our recent research showed that demethoxycurcumin (DMC), a component of curcumin, was superior to TMZ in its ability to inhibit proliferation and induce apoptosis of GSCs in vitro. In addition, the combined treatment of TMZ + DMC induced more obvious anti-GSC effects. However, in this study, no obvious synergistic anti-GSC effects of TMZ + DMC were found in vivo, while DMC was still superior to TMZ with respect to growth inhibition of GSCs in vivo. Furthermore, immunohistochemistry for proliferating cell nuclear antigen (PCNA) showed that such inhibitory effects were mainly related to the inhibition of cell proliferation rather than to apoptosis. However, a high concentration of DMC (50 mg/kg) alone or combined with TMZ could also induce approximately 10 % of the cells to undergo apoptosis according to a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Finally, an investigation of the underlying mechanism revealed that the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) 3 signaling pathway played an important role in the anti-GSC effects. When the JAK inhibitor AG490 was applied, the anti-GSC effects of DMC were enhanced. Taken together, the present work reveals that DMC is superior to TMZ with respect to its anti-GSC effects in vivo, which are mediated through the inhibition of the activation of the JAK/STAT3 pathway; however, DMC demonstrated no synergistic effects with TMZ.
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Mesangial cells (MCs), vascular smooth muscle-derived cells, contribute to glomerular injury by generating a number of cytokines such as tumor necrosis factor-α (TNF-α). Matrix metalloproteinases (MMPs), regulated by various stimuli, are important in remodeling of glomerular ECM, which leads to a number of renal diseases. We investigated whether TNF-α participated in the regulation of MMPs and explored signal pathways involved in TNF-α-induced MMPs expression in rat glomerular MCs. Western blot and RT-qPCR results showed that treatment with TNF-α significantly increased the expression of MMP-2, but not MMP-9 at both protein and mRNA levels in rat glomerular MCs. The extracellular signal-regulated kinase (ERK) and nuclear factor-kappaB (NF-κB) signal pathways were activated by TNF-α. Moreover, the activation of NF-κB pathway in rat MCs was effectively inhibited by PD98059, specific inhibitor of ERK, suggesting a role for ERK in regulating NF-κB function. PD98059 or NF-κB signal pathway selective inhibitor Bay 11-7082 effectively blocked TNF-α-induced expression of MMP-2 in rat MCs, as determined by gene and protein expression. C-jun N-terminal kinase (JNK) signal pathway had no effect on TNF-α-induced expression of MMP-2, even though it was also activated by TNF-α in rat MCs. Furthermore, TNF-α could induce the cell migration of rat MCs, whereas ERK signal pathway specific inhibitor PD98059 compromised the cell migration triggered by TNF-α. Thus, TNF-α upregulates the expression of MMP-2 via activation of ERK-dependent NF-κB pathway in rat MCs, which may contribute to the cell migration of rat MCs.
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Movimiento Celular/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Animales , Línea Celular , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Flavonoides/farmacología , Expresión Génica/efectos de los fármacos , Proteínas I-kappa B/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Células Mesangiales/citología , Células Mesangiales/efectos de los fármacos , Células Mesangiales/metabolismo , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , ARN Mensajero/metabolismo , RatasRESUMEN
Advancements in genomics have dramatically accelerated the research on medicinal plants, and the development of herbgenomics has promoted the "Project of 1K Medicinal Plant Genome" to decipher their genetic code. However, it is difficult to obtain their high-quality whole genomes because of the prevalence of polyploidy and/or high genomic heterozygosity. Whole genomes of 123 medicinal plants were published until September 2022. These published genome sequences were investigated in this review, covering their classification, research teams, ploidy, medicinal functions, and sequencing strategies. More than 1,000 institutes or universities around the world and 50 countries are conducting research on medicinal plant genomes. Diploid species account for a majority of sequenced medicinal plants. The whole genomes of plants in the Poaceae family are the most studied. Almost 40% of the published papers studied species with tonifying, replenishing, and heat-cleaning medicinal effects. Medicinal plants are still in the process of domestication as compared with crops, thereby resulting in unclear genetic backgrounds and the lack of pure lines, thus making their genomes more difficult to complete. In addition, there is still no clear routine framework for a medicinal plant to obtain a high-quality whole genome. Herein, a clear and complete strategy has been originally proposed for creating a high-quality whole genome of medicinal plants. Moreover, whole genome-based biological studies of medicinal plants, including breeding and biosynthesis, were reviewed. We also advocate that a research platform of model medicinal plants should be established to promote the genomics research of medicinal plants.
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Plantas Medicinales , Plantas Medicinales/genética , Fitomejoramiento , Genómica/métodos , Secuenciación Completa del Genoma , Productos Agrícolas/genética , Genoma de Planta/genéticaRESUMEN
Zygotic genome activation (ZGA) is a universal process in early embryogenesis of metazoan, when the quiescent zygotic nucleus initiates global transcription. However, the mechanisms related to massive genome activation and allele-specific expression (ASE) remain not well understood. Here, we develop hybrids from two deeply diverged (120 Mya) ascidian species to symmetrically document the dynamics of ZGA. We identify two coordinated ZGA waves represent early developmental and housekeeping gene reactivation, respectively. Single-cell RNA sequencing reveals that the major expression wave exhibits spatial heterogeneity and significantly correlates with cell fate. Moreover, allele-specific expression occurs in a species- rather than parent-related manner, demonstrating the divergence of cis-regulatory elements between the two species. These findings provide insights into ZGA in chordates.
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Cordados , Urocordados , Animales , Urocordados/genética , Alelos , Cigoto/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión GénicaRESUMEN
Mentha is a commonly used spice worldwide, which possesses medicinal properties and fragrance. These characteristics are conferred, at least partially, by essential oils such as menthol. In this study, a gap-free assembly with a genome size of 414.3 Mb and 31,251 coding genes was obtained for Mentha suaveolens 'Variegata'. Based on its high heterozygosity (1.5%), two complete haplotypic assemblies were resolved, with genome sizes of 401.9 and 405.7 Mb, respectively. The telomeres and centromeres of each haplotype were almost fully annotated. In addition, we detected a total of 41,135 structural variations. Enrichment analysis demonstrated that genes involved in terpenoid biosynthesis were affected by these structural variations. Analysis of volatile metabolites showed that M. suaveolens mainly produces piperitenone oxide rather than menthol. We identified three genes in the M. suaveolens genome which encode isopiperitenone reductase (ISPR), a key rate-limiting enzyme in menthol biosynthesis. However, the transcription levels of ISPR were low. Given that other terpenoid biosynthesis genes were expressed, M. suaveolens ISPRs may account for the accumulation of piperitenone oxide in this species. The findings of this study may provide a valuable resource for improving the detection rate and accuracy of genetic variants, thereby enhancing our understanding of their impact on gene function and expression. Moreover, our haplotype-resolved gap-free genome assembly offers novel insights into molecular marker-assisted breeding of Mentha.
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Cepharanthine is a secondary metabolite isolated from Stephania. It has been reported that it has anti-conronaviruses activities including severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Here, we assemble three Stephania genomes (S. japonica, S. yunnanensis, and S. cepharantha), propose the cepharanthine biosynthetic pathway, and assess the antiviral potential of compounds involved in the pathway. Among the three genomes, S. japonica has a near telomere-to-telomere assembly with one remaining gap, and S. cepharantha and S. yunnanensis have chromosome-level assemblies. Following by biosynthetic gene mining and metabolomics analysis, we identify seven cepharanthine analogs that have broad-spectrum anti-coronavirus activities, including SARS-CoV-2, Guangxi pangolin-CoV (GX_P2V), swine acute diarrhoea syndrome coronavirus (SADS-CoV), and porcine epidemic diarrhea virus (PEDV). We also show that two other genera, Nelumbo and Thalictrum, can produce cepharanthine analogs, and thus have the potential for antiviral compound discovery. Results generated from this study could accelerate broad-spectrum anti-coronavirus drug discovery.
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Alphacoronavirus , Benzodioxoles , Bencilisoquinolinas , Stephania , Animales , Porcinos , China/epidemiología , SARS-CoV-2 , Antivirales/farmacologíaRESUMEN
Lotus (Nelumbo nucifera), an ancient aquatic plant, possesses a unique pharmacological activity that is primarily contributed by benzylisoquinoline alkaloids (BIAs). However, only few genes and enzymes involved in BIA biosynthesis in N. nucifera have been isolated and characterized. In the present study we identified the regiopromiscuity of an O-methyltransferase, designated NnOMT6, isolated from N. nucifera; NnOMT6 was found to catalyze the methylation of monobenzylisoquinoline 6-O/7-O, aporphine skeleton 6-O, phenylpropanoid 3-O, and protoberberine 2-O. We further probed the key residues affecting NnOMT6 activity via molecular docking and molecular dynamics simulation. Verification using site-directed mutagenesis revealed that residues D316, N130, L135, N176A, D269, and E328 were critical for BIA O-methyltransferase activities; furthermore, N323A, a mutant of NnOMT6, demonstrated a substantial increase in catalytic efficiency for BIAs and a broader acceptor scope compared with wild-type NnOMT6. To the best of our knowledge, this is the first study to report the O-methyltransferase activity of an aporphine skeleton without benzyl moiety substitutions in N. nucifera. The study findings provide biocatalysts for the semisynthesis of related medical compounds and give insights into protein engineering to strengthen O-methyltransferase activity in plants.
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Polygala tenuifolia is a perennial medicinal plant that has been widely used in traditional Chinese medicine for treating mental diseases. However, the lack of genomic resources limits the insight into its evolutionary and biological characterization. In the present work, we reported the P. tenuifolia genome, the first genome assembly of the Polygalaceae family. We sequenced and assembled this genome by a combination of Illumnina, PacBio HiFi, and Hi-C mapping. The assembly includes 19 pseudochromosomes covering ~92.68% of the assembled genome (~769.62 Mb). There are 36 463 protein-coding genes annotated in this genome. Detailed comparative genome analysis revealed that P. tenuifolia experienced two rounds of whole genome duplication that occurred ~39-44 and ~18-20 million years ago, respectively. Accordingly, we systematically reconstructed ancestral chromosomes of P. tenuifolia and inferred its chromosome evolution trajectories from the common ancestor of core eudicots to the present species. Based on the transcriptomics data, enzyme genes and transcription factors involved in the synthesis of triterpenoid saponin in P. tenuifolia were identified. Further analysis demonstrated that whole-genome duplications and tandem duplications play critical roles in the expansion of P450 and UGT gene families, which contributed to the synthesis of triterpenoid saponins. The genome and transcriptome data will not only provide valuable resources for comparative and functional genomic researches on Polygalaceae, but also shed light on the synthesis of triterpenoid saponin.
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Artemisia annua is the only known plant source of the potent antimalarial artemisinin, which occurs as the low- and high-artemisinin producing (LAP and HAP) chemotypes. Nevertheless, the different mechanisms of artemisinin producing between these two chemotypes were still not fully understood. Here, we performed a comprehensive analysis of genome resequencing, metabolome, and transcriptome data to systematically compare the difference in the LAP chemotype JL and HAP chemotype HAN. Metabolites analysis revealed that 72.18% of sesquiterpenes was highly accumulated in HAN compared to JL. Integrated omics analysis found a DBR2-Like (DBR2L) gene may be involved in artemisinin biosynthesis. DBR2L was highly homologous with DBR2, belonged to ORR3 family, and had the DBR2 activity of catalyzing artemisinic aldehyde to dihydroartemisinic aldehyde. Genome resequencing and promoter cloning revealed that complicated variations existed in DBR2L promoters among different varieties of A. annua and were clustered into three variation types. The promoter activity of diverse variant types showed obvious differences. Furthermore, the core region (-625 to 0) of the DBR2L promoter was identified and candidate transcription factors involved in DBR2L regulation were screened. Thus, the result indicates that DBR2L is another key enzyme involved in artemisinin biosynthesis. The promoter variation in DBR2L affects its expression level, and thereby may result in the different yield of artemisinin in varieties of A. annua. It provides a novel insight into the mechanism of artemisinin-producing difference in LAP and HAP chemotypes of A. annua, and will assist in a high yield of artemisinin in A. annua.
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Despite polymorphic duplicate genes' importance for the early stages of duplicate gene evolution, they are less studied than old gene duplicates. Two essential questions thus remain poorly addressed: how does dosage sensitivity, imposed by stoichiometry in protein complexes or by X chromosome dosage compensation, affect the emergence of complete duplicate genes? Do introns facilitate intergenic and intragenic chimaerism as predicted by the theory of exon shuffling? Here, we analysed new data for Drosophila and public data for humans, to characterize polymorphic duplicate genes with respect to dosage, exon-intron structures and allele frequencies. We found that complete duplicate genes are under dosage constraint induced by protein stoichiometry but potentially tolerated by X chromosome dosage compensation. We also found that in the intron-rich human genome, gene fusions and intragenic duplications extensively use intronic breakpoints generating in-frame proteins, in accordance with the theory of exon shuffling. Finally, we found that only a small proportion of complete or partial duplicates are at high frequencies, indicating the deleterious nature of dosage or gene structural changes. Altogether, we demonstrate how mechanistic factors including dosage sensitivity and exon-intron structure shape the short-term functional consequences of gene duplication.
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Barajamiento de ADN , Drosophila , Duplicación de Gen , Animales , Compensación de Dosificación (Genética) , Drosophila/genética , Exones , Dosificación de Gen , Genes Duplicados , Humanos , IntronesRESUMEN
The genetic differentiation of populations is a key parameter in population genetic investigations. Wright's F(ST) (and its relatives such as G(ST) ) has been a standard measure of differentiation. However, the deficiencies of these indexes have been increasingly realized in recent years, leading to some new measures being proposed, such as Jost's D (Molecular Ecology, 2008; 17, 4015). The existence of these new metrics has stimulated considerable debate and induced some confusion on which statistics should be used for estimating population differentiation. Here, we report a simulation study with neutral microsatellite DNA loci under a finite island model to compare the performance of G(ST) and D, particularly under nonequilibrium conditions. Our results suggest that there exist fundamental differences between the two statistics, and neither G(ST) nor D operates satisfactorily in all situations for quantifying differentiation. D is very sensitive to mutation models but G(ST) noticeably less so, which limits D's utility in population parameter estimation and comparisons across genetic markers. Also, the initial heterozygosity of the starting populations has some important effects on both the individual behaviours of G(ST) and D and their relative behaviours in early differentiation, and this effect is much greater for D than G(ST) . In the early stages of differentiation, when initial heterozygosity is relatively low (<0.5, if the number of subpopulations is large), G(ST) increases faster than D; the opposite is true when initial heterozygosity is high. Therefore, the state of the ancestral population appears to have some lasting impacts on population differentiation. In general, G(ST) can measure differentiation fairly well when heterozygosity is low whatever the causes; however, when heterozygosity is high (e.g. as a result of either high mutation rate or high initial heterozygosity) and gene flow is moderate to strong, G(ST) fails to measure differentiation. Interestingly, when population size is not very small (e.g. N ≥ 1000), G(ST) measures differentiation quite linearly with time over a long duration when gene flow is absent or very weak even if mutation rate is not low (e.g. µ = 0.001). In contrast, D, as a differentiation measure, performs rather robustly in all these situations. In practice, both indexes should be calculated and the relative levels of heterozygosities (especially H(S) ) and gene flow taken into account. We suggest that a comparison of the two indexes can generate useful insights into the evolutionary processes that influence population differentiation.
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Genética de Población/métodos , Repeticiones de Microsatélite/genética , Evolución Biológica , Simulación por Computador , Flujo Génico , Marcadores Genéticos , Variación Genética , Heterocigoto , Modelos Genéticos , Mutación , Dinámica Poblacional , Programas Informáticos , Estadística como AsuntoRESUMEN
BACKGROUND: Treatment with atorvastatin (ATO) or dietary control has been demonstrated to benefit patients with non-alcoholic fatty liver disease (NAFLD) and hyperlipidemia. However, little is known on whether combination of dietary control and ATO treatment could enhance the therapeutic effect. METHODS: We employed a rat model of NAFLD to examine the therapeutic efficacy of dietary control and/or ATO treatment. Sprague-Dawley rats were fed with normal chow diet as normal controls or with high fat diet (HFD) for 12 weeks to establish NAFLD. The NAFLD rats were randomized and continually fed with HFD, with normal chow diet, with HFD and treated with 30 mg/kg of ATO or with normal chow diet and treated with the same dose of ATO for 8 weeks. Subsequently, the rats were sacrificed and the serum lipids, aminotransferase, hepatic lipids, and liver pathology were characterized. The relative levels of fatty acid synthesis and ß-oxidation gene expression in hepatic tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Hepatic expression of hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was determined by Western blot assay. RESULTS: While continual feeding with HFD deteriorated NAFLD and hyperlipidemia, treatment with dietary control, ATO or ATO with dietary control effectively improved serum and liver lipid metabolism and liver function. In comparison with ATO treatment, dietary control or combined with ATO treatment significantly reduced the liver weight and attenuated the HFD-induced hyperlipidemia and liver steatosis in rats. Compared to ATO treatment or dietary control, combination of ATO and dietary control significantly reduced the levels of serum total cholesterol and low density lipoprotein cholesterol (LDL-C). However, the combination therapy did not significantly improve triglyceride and free fatty acid metabolism, hepatic steatosis, and liver function, as compared with dietary control alone. CONCLUSIONS: ATO treatment effectively improved NAFLD-related hyperlipidemia and inhibited liver steatosis, accompanied by modulating the expression of genes for regulating lipid metabolism. ATO enhanced the effect of dietary control on reducing the levels of serum total cholesterol and LDL-C, but not triglyceride, free fatty acid and hepatic steatosis in HFD-induced fatty liver and hyperlipidemia in rats.
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Grasas de la Dieta/administración & dosificación , Hígado Graso/dietoterapia , Hígado Graso/tratamiento farmacológico , Ácidos Heptanoicos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hiperlipidemias/dietoterapia , Hiperlipidemias/tratamiento farmacológico , Pirroles/farmacología , Animales , Atorvastatina , Terapia Combinada , Hígado Graso/metabolismo , Regulación de la Expresión Génica , Ácidos Heptanoicos/uso terapéutico , Hidroximetilglutaril-CoA Reductasas/genética , Hidroximetilglutaril-CoA Reductasas/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hiperlipidemias/metabolismo , Metabolismo de los Lípidos , Lípidos/sangre , Lípidos/química , Hígado/química , Hígado/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico , Tamaño de los Órganos , PPAR alfa/genética , Pirroles/uso terapéutico , Ratas , Ratas Sprague-Dawley , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Transaminasas/sangreRESUMEN
OBJECTIVE: To study the effects of soybean isoflavone on liver lipid, serum lipid, antioxidant index and hepatic lipid metabolism associated factors in nonalcoholic fatty liver rats. METHODS: Thirty-six male rats (SD) were randomly divided into four groups by weight: normal control group, nonalcoholic fatty liver disease (NAFLD) model control group, low-dose isoflavone treatment group (10 mg/kg) and high-dose isoflavone group (20 mg/kg), 9 rats in each group. Normal control rats were fed with D12450B (10% fat energy), model control and isoflavone intervention rats were fed with D12492 (60% fat energy). Twelve weeks later, liver lipid, serum lipid and antioxidant index were observed. Liver sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS) and peroxisome proliferators activated receptor alpha (PPAR alpha) were detected by western blotting. RESULTS: Liver triglyceride (TG) in normal control group, NAFLD model control group, low-dose isoflavone group and high-dose isoflavone group were (8.11 ± 4.13), (57.06 ± 16.95), (31.26 ± 10.48), (31.38 ± 13.25) mmol/mg protein, respectively (F = 22.569, P < 0.01); liver free fatty acid (FFA) were (0.030 ± 0.007), (0.042 ± 0.009), (0.038 ± 0.009), (0.032 ± 0.005) µmol/mg protein, respectively (F = 4.857, P < 0.01); liver superoxide dismutase (SOD) activity were (502.29 ± 23.71), (201.83 ± 16.99), (228.93 ± 21.71), (238.08 ± 15.96) U/mg protein, respectively (F = 9.555, P < 0.01); liver malondialdehyde (MDA) were (1.29 ± 0.29), (2.85 ± 0.73), (2.07 ± 0.49), (2.03 ± 0.37) nmol/mg protein, respectively (F = 13.449, P < 0.01); SREBP-1c protein expression were 0.45 ± 0.16, 1.42 ± 0.30, 1.02 ± 0.31, 0.47 ± 0.27, respectively (F = 24.515, P < 0.01); FAS protein expression were 0.27 ± 0.08, 1.97 ± 0.47, 1.35 ± 0.30, 0.49 ± 0.12, respectively (F = 60.361, P < 0.01); PPARα protein expression were 2.03 ± 0.56, 0.41 ± 0.17, 0.81 ± 0.27, 0.66 ± 0.16, respectively (F = 37.97, P < 0.01). CONCLUSION: Soy isoflavone can reduce the hepatic lipid deposition and increase antioxidant capacity, the mechanism may be related to inhibition of SREBP-1c and activation of PPARα expression in liver.
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Hígado Graso/metabolismo , Glycine max/química , Isoflavonas/farmacología , Metabolismo de los Lípidos , Hígado/metabolismo , Animales , Ácido Graso Sintasas/metabolismo , Hígado/efectos de los fármacos , Masculino , Enfermedad del Hígado Graso no Alcohólico , PPAR alfa/metabolismo , Ratas , Ratas Sprague-Dawley , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismoRESUMEN
OBJECTIVE: To explore the effect of different doses of 1,25-(OH)(2)VitD(3) early supplementation on airway inflammation and lung inflammatory factors in baby rats with asthma. METHODS: Forty male weaned Wistar rats were divided into normal group, model group, low 1,25-(OH)(2)VitD(3) group, middle 1,25-(OH)(2)VitD(3) group, high 1,25-(OH)(2)VitD(3) group using random number table (8 rats each group). The rats in low, middle and high 1,25-(OH)(2)VitD(3) groups were given 1, 4, 10 µg/kg of 1,25-(OH)(2)VitD(3) every other day by intraperitoneal injection respectively for 25 days. Except normal group, the rats in other groups were challenged with ovalbumin to establish the asthma model. The pathologic changes of lung tissue, the total white blood cell and classified cell counts in bronchoalveolar lavage fluid (BALF) were measured. The concentrations of IL-4, IL-5 and IFN-γ in serum and BALF were measured by ELISA method. RESULTS: The level of total white blood cell counts in BALF were (5.98 ± 1.67)×10(5)/ml, (25.34 ± 4.28)×10(5)/ml, (17.24 ± 3.3)×10(5)/ml, (9.31 ± 3.37)×10(5)/ml, (45.1 ± 15.75)×10(5)/ml, respectively (F = 33.453, P < 0.01). The percent ratio of EOS in BALF were (1.44 ± 0.78)%, (17.81 ± 6.88)%, (15.00 ± 5.70)%, (8.89 ± 3.66)%, (25.88 ± 5.57)%, respectively (F = 27.299, P < 0.01). The level of IL-4 in serum of normal, model, low, middle and high-1,25-(OH)(2)VitD(3) groups were (0.62 ± 0.54), (7.57 ± 1.04), (3.58 ± 0.56), (2.70 ± 0.78) and (5.27 ± 0.30) pg/ml, respectively (F = 116.287, P < 0.01); IL-5 in resume were (32.20 ± 4.23), (67.14 ± 18.14), (37.51 ± 0.47), (40.69 ± 2.47) and (124.60 ± 36.19) pg/ml, respectively (F = 23.902, P < 0.01); IFN-γ in serum were (79.71 ± 10.08), (49.06 ± 4.46), (59.15 ± 2.51), (59.27 ± 2.33) and (53.85 ± 1.97) pg/ml, respectively (F = 39.954, P < 0.01). Also in BLAF, the IL-4 of all groups were (0.51 ± 0.30), (102.92 ± 54.61), (8.64 ± 4.07), (3.10 ± 1.28) and (33.67 ± 8.1) pg/ml, respectively (F = 24.062, P < 0.01); the IFN-γ were (247.37 ± 189.18), (43.82 ± 13.76), (81.32 ± 17.07), (86.50 ± 14.26) and (59.89 ± 34.17) pg/ml, respectively (F = 7.157, P < 0.01); the IL-5 in BALF were (38.81 ± 0.60), (80.48 ± 17.90), (45.11 ± 1.33), (43.39 ± 1.11) and (149.60 ± 45.87) pg/ml, respectively (F = 35.978, P < 0.01). Pathologic changes in lung of asthma rat groups were obvious. The lung pathologic changes in low and middle dose groups showed a significant improvement compared to the asthma group and high dosage group showed more serious pathologic changes compared to the low and middle dose groups. CONCLUSION: Intervention with appropriate dose of 1,25-(OH)(2)VitD(3) in the early life could improve lung pathologic changes and reduce the effect of inflammatory factors in air way of baby rat asthma model. However, overdose might play detrimental effect.