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The apetala/ethylene responsive factor (AP2/ERF) family is one of the largest plant-specific transcription factors and plays a vital role in plant development and response to stress. The apetala 2.4 (RAP2.4) gene is a member of the AP2/ERF family. In this study, ClRAP2.4 cDNA fragment with 768bp open reading frame was cloned and the resistance of ClRAP2.4 overexpression to low temperature was investigated to understand whether RAP2.4 is involved in low-temperature stress in chrysanthemum (Chrysamthemum lavandulifolium ). Phylogenetic analysis showed that ClRAP2.4 belonged to the DREB subfamily and was most closely related to AT1G22190. ClRAP2.4 was localised in cell nucleus and promotes transcriptional activation in yeast. In addition, ClRAP2.4 was transformed by using the Agrobacterium -mediated leaf disc method, and four overexpression lines (OX-1, OX-2, OX-7, and OX-8) were obtained. The activities of superoxide dismutase and peroxidase, and proline content in leaves in the four overexpression line were higher than those in the wild type (WT), whereas the electrical conductivity and malondialdehyde content were decreased, indicating that the tolerance of plants with ClRAP2.4 overexpression to cold stress was increased. RNA-Seq showed 390 differentially expressed genes (DEGs) between the transgenic and WT plants(229 upregulated, 161 downregulated). The number of ABRE , LTR , and DRE cis -elements in the promoters of DEGs were 175, 106, and 46, respectively. The relative expression levels of ClCOR , ClFe/MnSOD , ClPOD , ClNCL , ClPLK , ClFAD , and ClPRP in the transgenic plants were higher than those in WT plants at low temperatures. These data suggest that ClRAP2.4 may increase chrysanthemum tolerance to cold stress.
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Chrysanthemum , Resposta ao Choque Frio , Resposta ao Choque Frio/genética , Chrysanthemum/genética , Chrysanthemum/metabolismo , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismoRESUMO
The clinical application of anthracyclines such as doxorubicin (DOX) is limited due to their cardiotoxicity. N6-methyladenosine (m6A) plays an essential role in numerous biological processes. However, the roles of m6A and m6A demethylase ALKBH5 in DOX-induced cardiotoxicity (DIC) remain unclear. In this research, DIC models were constructed using Alkbh5-knockout (KO), Alkbh5-knockin (KI), and Alkbh5-myocardial-specific knockout (ALKBH5flox/flox, αMyHC-Cre) mice. Cardiac function and DOX-mediated signal transduction were investigated. As a result, both Alkbh5 whole-body KO and myocardial-specific KO mice had increased mortality, decreased cardiac function, and aggravated DIC injury with severe myocardial mitochondrial damage. Conversely, ALKBH5 overexpression alleviated DOX-mediated mitochondrial injury, increased survival, and improved myocardial function. Mechanistically, ALKBH5 regulated the expression of Rasal3 in an m6A-dependent manner through posttranscriptional mRNA regulation and reduced Rasal3 mRNA stability, thus activating RAS3, inhibiting apoptosis through the RAS/RAF/ERK signaling pathway, and alleviating DIC injury. These findings indicate the potential therapeutic effect of ALKBH5 on DIC.
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Identification of the causes for congenital heart disease (CHD) is a prerequisite for precise prevention and personalized treatment of CHD. Zhao et al.1 show increased that gestational serum palmitic acid (PA) predisposes offspring to CHD by perturbating the MARS/K-Hcy/GATA4 signaling pathway.
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Cardiopatias Congênitas , Ácido Palmítico , Humanos , Cardiopatias Congênitas/etiologia , Estudos de Casos e ControlesRESUMO
To explore the effects of different long-term fertilization treatments on soil microbial diversity and community structure in the drylands of an agro-pastoral ecotone, a long-term fertilization experiment at the Inner Mongolia cultivated land conservation science observation and experiment station, Ministry of Agriculture, and rural areas was taken as the research object. Four treatments, including no fertilizer (CK), single nitrogen fertilizer (NF), single chemical fertilizer (CF), and the combined application of organic manure and chemical fertilizer (CFM), were selected for the collection of 0-10 cm and 10-20 cm soil at potato maturity 16 years after the experiment (2019). High-throughput sequencing technology was used to assess the soil bacterial and fungal communities to explore the effects of different fertilization measures on soil quality from the perspective of microorganisms, and the partial least squares path model (PLS-PM) was used to reveal the key environmental driving factors of soil microbial community alternation and crop yield improvement in dryland during fertilization mode transformation. The results showed that:â the CF and CFM treatments significantly improved soil fertility, but the effect of the latter was significantly better than that of the former. Soil available nitrogen, available phosphorus, and available potassium in the CFM treatment increased by 131.9%-174.7%, 216.9%-283.3%, and 103.3%-109.3%, respectively, and organic matter and total nitrogen content also increased significantly. The CF treatment still maintained a high soil pH, whereas the NF treatment significantly decreased soil pH and had little effect in improving soil fertility. â¡ Compared with that under CK, the NF treatment significantly reduced the soil bacterial Chao1 and Shannon index, and the CFM treatment significantly increased the soil bacterial species richness, Chao1 index, and soil fungal Shannon index, whereas soil bacterial and fungal diversity in the CF treatment did not reach a significant difference level with CK. ⢠The soil microbial community composition at 0-10 cm and 10-20 cm was similar. The CFM treatment increased the relative abundance of soil beneficial bacteria and decreased the relative abundance of pathogenic bacteria. The relative abundance of dominant bacteria such as Proteobacteria, Bacteroidetes, and Gemmatimonadetes increased. The relative abundances of Actinobacteria, Ascomycota, and Basidiomycota were decreased, whereas the NF and CF treatments showed the opposite trend. ⣠PLS-PM analysis showed that with the gradual change in fertilization mode from CKâNFâCFâCFM, the driving factors affecting microbial community succession and yield increase were also changed from soil pHâsoil NPK contentâsoil pH, SOM, and NPK content. In general, long-term fertilization had significant effects on soil chemical properties and microbial communities in drylands in the agro-pastoral ecotone. As the optimal fertilization choice, CFM was significantly better than NF and CF in improving soil fertility and inhibiting the growth of pathogenic microorganisms. The number of pathogens in long-term non-fertilization and unbalanced fertilization soil was significantly increased, and the risk of crop infection to indigenous diseases was increased. The research results can provide scientific reference for farmland nutrient balance management and soil microenvironment improvement of the agricultural ecosystem in the agro-pastoral ecotone in North China.
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Microbiota , Solo , Solo/química , Microbiologia do Solo , Agricultura , Bactérias , Fertilizantes/análise , Nitrogênio/análiseRESUMO
Background Dilated cardiomyopathy (DCM), characterized by progressive left ventricular enlargement and systolic dysfunction, is the most common type of cardiomyopathy and a leading cause of heart failure and cardiac death. Accumulating evidence underscores the critical role of genetic defects in the pathogenesis of DCM, and >250 genes have been implicated in DCM to date. However, DCM is of substantial genetic heterogeneity, and the genetic basis underpinning DCM remains elusive in most cases. Methods and Results By genome-wide scan with microsatellite markers and genetic linkage analysis in a 4-generation family inflicted with autosomal-dominant DCM, a new locus for DCM was mapped on chromosome 15q13.1-q13.3, a 4.77-cM (≈3.43 Mbp) interval between markers D15S1019 and D15S1010, with the largest 2-point logarithm of odds score of 5.1175 for the marker D15S165 at recombination fraction (θ)=0.00. Whole-exome sequencing analyses revealed that within the mapping chromosomal region, only the mutation in the KLF13 gene, c.430G>T (p.E144X), cosegregated with DCM in the family. In addition, sequencing analyses of KLF13 in another cohort of 266 unrelated patients with DCM and their available family members unveiled 2 new mutations, c.580G>T (p.E194X) and c.595T>C (p.C199R), which cosegregated with DCM in 2 families, respectively. The 3 mutations were absent from 418 healthy subjects. Functional assays demonstrated that the 3 mutants had no transactivation on the target genes ACTC1 and MYH7 (2 genes causally linked to DCM), alone or together with GATA4 (another gene contributing to DCM), and a diminished ability to bind the promoters of ACTC1 and MYH7. Add, the E144X-mutant KLF13 showed a defect in intracellular distribution. Conclusions This investigation indicates KLF13 as a new gene predisposing to DCM, which adds novel insight to the molecular pathogenesis underlying DCM, implying potential implications for prenatal prevention and precision treatment of DCM in a subset of patients.
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Cardiomiopatia Dilatada , Humanos , Cardiomiopatia Dilatada/metabolismo , Mutação , Linhagem , Proteínas Repressoras/genética , Proteínas de Ciclo Celular/genética , Fatores de Transcrição Kruppel-Like/genéticaRESUMO
Background Atrial fibrillation (AF) is the most common form of clinical cardiac dysrhythmia responsible for thromboembolic cerebral stroke, congestive heart failure, and death. Aggregating evidence highlights the strong genetic basis of AF. Nevertheless, AF is of pronounced genetic heterogeneity, and in an overwhelming majority of patients, the genetic determinants underpinning AF remain elusive. Methods and Results By genome-wide screening with polymorphic microsatellite markers and linkage analysis in a 4-generation Chinese family affected with autosomal-dominant AF, a novel locus for AF was mapped to chromosome 1q24.2-q25.1, a 3.20-cM (≈4.19 Mbp) interval between markers D1S2851 and D1S218, with the greatest 2-point logarithm of odds score of 4.8165 for the marker D1S452 at recombination fraction=0.00. Whole-exome sequencing and bioinformatics analyses showed that within the mapping region, only the mutation in the paired related homeobox 1 (PRRX1) gene, NM_022716.4:c.319C>T;(p.Gln107*), cosegregated with AF in the family. In addition, sequencing analyses of PRRX1 in another cohort of 225 unrelated patients with AF revealed a new mutation, NM_022716.4:c.437G>T; (p.Arg146Ile), in a patient. The 2 mutations were absent in 908 control subjects. Biological analyses in HeLa cells demonstrated that the 2 mutants had significantly diminished transactivation on the target genes ISL1 and SHOX2 and markedly decreased ability to bind the promoters of ISL1 and SHOX2 (2 genes causally linked to AF), although with normal intracellular distribution. Conclusions This study first indicates that PRRX1 loss-of-function mutations predispose to AF, which provides novel insight into the molecular pathogenesis underpinning AF, implying potential implications for precisive prophylaxis and management of AF.
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Fibrilação Atrial , Proteínas de Homeodomínio , Fibrilação Atrial/genética , Predisposição Genética para Doença , Proteínas de Homeodomínio/genética , Humanos , MutaçãoRESUMO
Bromodomain-containing protein 4 (BRD4) is one of the most important members in the bromodomain and extra terminal domain(BET) family, it plays an important role in cellular physiology in human body, such as cell cycles, cell proliferation, and immune response. Recent studies have shown that BRD4 is associated with occurrence and development of acute myeloblastic leukemia, multiple myeloma and lymphoma. The mechanisms of BRD4 in hematologic malignancies including the regulation of c-Myc expression, and participation of the composition of super-enhancer, etc. At present, many kinds of inhibitors have been developed to target inhibit BRD4 for therapy in hematologic malignancies, and some of BRD4 inhibitors have entered phase â ¡ clinical trials, which suggested that BRD4 inhibitors are expected to become new therapeutic agents for hematologic malignancies. In this review, the research advance of BRD4 and BRD4 inhibitors in hematologic malignancies was summarized briefly.
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Neoplasias Hematológicas , Fatores de Transcrição , Proteínas de Ciclo Celular , Proliferação de Células , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Proteínas Nucleares , Domínios ProteicosRESUMO
The characteristic tensile strain of reactive powder concrete is a critical indicator of its resistance to cracking. In order to study its crack resistance performance, in this study, we investigated changes over time in the characteristic tensile strain patterns of reactive powder concrete. An axial tensile test was performed to obtain the stress-strain curves of reactive powder concrete after curing ages from 3 to 56 days, and then we identified changes over time in the initial and ultimate tensile strain patterns. An analysis was conducted to determine the correlation between the initial tensile strain and the ratio of tensile strength to elastic modulus. The correlations between the ultimate tensile strain and its curing age as well as that of the ultimate tensile strain with its tensile strength and its compressive strength were established, and an approach was proposed for calculating the characteristic age of reactive powder concrete.
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BACKGROUND: Myocardial infarction (MI) triggers a strong inflammatory response that is associated with myocardial fibrosis and cardiac remodeling. Interleukin (IL)-1ß and IL-18 are key players in this response and are controlled by NLRP3-inflammatory bodies. Oridonin is a newly reported NLRP3 inhibitor with strong anti-inflammatory activity. We hypothesized that the covalent NLRP3 inhibitor Oridonin could reduce IL-1ß and IL-18 expression and ameliorate myocardial fibrosis after myocardial infarction in mice, improve poor heart remodeling, and preserve heart function. METHODS: Male C57BL/6 mice were subjected to left coronary artery ligation to induce MI and then treated with Oridonin (1, 3, or 6 mg/kg), MCC950 (10 mg/kg), CY-09 (5 mg/kg) or saline three times a week for two weeks. Four weeks after MI, cardiac function and myocardial fibrosis were assessed. In addition, myocardial expressions of inflammatory factors and fibrotic markers were analyzed by western blot, immunofluorescence, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction. RESULTS: Oridonin treatment preserved left ventricular ejection fraction and fractional shortening, and markedly limited the myocardial infarct size in treated mice. The myocardial fibrosis was lower in the 1 mg/kg group (15.98 ± 1.64)%, 3 mg/kg group (17.39 ± 2.45)%, and 6 mg/kg group (16.76 ± 3.06)% compared to the control group (23.38 ± 1.65)%. Moreover, similar with the results of Oridonin, MCC950 and CY-09 also preserved cardiac function and reduced myocardial fibrosis. The expression levels of NLRP3, IL-1ß and IL-18 were decreased in the Oridonin treatment group compared to non-treated group. In addition, myocardial macrophage and neutrophil influxes were attenuated in the Oridonin treated group. CONCLUSIONS: The covalent NLRP3-inflammasome inhibitor Oridonin reduces myocardial fibrosis and preserves cardiac function in a mouse MI model, which indicates potential therapeutic effect of Oridonin on acute MI patients.
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Anti-Inflamatórios/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Inflamassomos/antagonistas & inibidores , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Animais , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Furanos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Indenos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Receptores de Interleucina-18/metabolismo , Transdução de Sinais , Volume Sistólico/efeitos dos fármacos , Sulfonamidas , Sulfonas/farmacologia , Tiazolidinas/farmacologia , Tionas/farmacologiaRESUMO
Both the presence of, and the important contribution to growth and development made by TCP transcription factors, have been established in various plant species. Here, a TCP4 homolog isolated from Chrysanthemum nankingense was shown to be more strongly transcribed in the diploid than in the autotetraploid form of the species. CnTCP4 was shown to encode a member of the class II TCP family and to be transcribed most strongly in the leaf and ligulate flowers. Its transcription was found to be substantially inhibited by spraying the plant with the synthetic cytokinin 6-benzylaminopurine. The transient expression of CnTCP4 in onion epidermal cells showed that its product localized to the nucleus, and a yeast one hybrid assay suggested that its product had transcriptional activation ability. The constitutive expression of CnTCP4 in fission yeast suppressed cell proliferation, inducing the formation of longer and a higher frequency of multinuclated cells. Its constitutive expression in Arabidopsis thaliana reduced the size of the leaves. The presence of the transgene altered the transcription of a number of cell division-related genes. A yeast one hybrid assay identified a second TCP gene (CnTCP2) able to interact with the CnTCP4 promoter. A transient expression experiment in Nicotiana benthamiana leaves showed that CnTCP2 was able to activate the CnTCP4 promoter. Like CnTCP4, CnTCP2 was shown to encode a member of the class II TCP family, to be transcribed most strongly in the leaf and ligulate flowers, and to be suppressed by exogenous 6-benzylaminopurine treatment. The CnTCP2 protein also localized to the nucleus, but had no transcriptional activation ability. Its constitutive expression in A. thaliana had similar phenotypic consequences to those induced by CnTCP4.
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Arabidopsis/genética , Divisão Celular/genética , Chrysanthemum/genética , Expressão Gênica , Fatores de Transcrição/genética , Leveduras/genética , Sequência de Aminoácidos , Arabidopsis/classificação , Arabidopsis/metabolismo , Perfilação da Expressão Gênica , Fenótipo , Filogenia , Regiões Promotoras Genéticas , Transcriptoma , Leveduras/classificação , Leveduras/metabolismoRESUMO
OBJECTIVE: To assess the methodological quality of systematic reviews and meta-analyses regarding acupuncture intervention for stroke and the primary studies within them. METHODS: Two researchers searched PubMed, Cumulative index to Nursing and Allied Health Literature, Embase, ISI Web of Knowledge, Cochrane, Allied and Complementary Medicine, Ovid Medline, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Wanfang and Traditional Chinese Medical Database to identify systematic reviews and meta-analyses about acupuncture for stroke published from the inception to December 2016. Review characteristics and the criteria for assessing the primary studies within reviews were extracted. The methodological quality of the reviews was assessed using adapted Oxman and Guyatt Scale. The methodological quality of primary studies was also assessed. RESULTS: Thirty-two eligible reviews were identified, 15 in English and 17 in Chinese. The English reviews were scored higher than the Chinese reviews (P=0.025), especially in criteria for avoiding bias and the scope of search. All reviews used the quality criteria to evaluate the methodological quality of primary studies, but some criteria were not comprehensive. The primary studies, in particular the Chinese reviews, had problems with randomization, allocation concealment, blinding, dropouts and withdrawals, intent-to-treat analysis and adverse events. CONCLUSIONS: Important methodological flaws were found in Chinese systematic reviews and primary studies. It was necessary to improve the methodological quality and reporting quality of both the systematic reviews published in China and primary studies on acupuncture for stroke.
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Terapia por Acupuntura , Metanálise como Assunto , Acidente Vascular Cerebral/terapia , Revisões Sistemáticas como Assunto , Humanos , Viés de Publicação , PublicaçõesRESUMO
Flower bud formation and flowering in chrysanthemums occur under short day conditions (SD), but the molecular basis for the switch to reproductive growth is less well understood than in model plants. Here, a spontaneous mutant able to flower under long days is described. In an attempt to reveal the pathway(s) involved in the formation of flower buds under contrasting daylengths, transcriptome sequencing was carried out in plants grown both under SD and long day conditions (LD). A number of differentially transcribed genes involved in the various known flowering pathways were identified. Both circadian clock genes and Chrysanthemum FLOWERING LOCUS T Like3 (CmFTL3) were up-regulated under SD, thereby inducing floral bud formation and flowering. The gibberellin (GA) signaling pathway-related genes Gibberellin 20-oxidase (GA20ox) and Gibberellin receptor (GID1) were up-regulated in the mutant under LD, while the catabolic genes Gibberellin 2-oxidase (GA2ox) and GA-INSENSITIVE (GAI) were down-regulated, thereby inducing the transcription of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and LEAFY (LFY). The GA content of the leaf was higher in the mutant than in the wild type (WT) under LD and SD, and the mutant has more branching than WT plants under LD or SD. When treated with GA, the mutant flowered earlier under both SD and LD relative to WT, but there was no detectable phenotype difference between the two lines. The indication was that the photoperiod pathway majorly regulates flower bud formation and flowering time in chrysanthemums under SD. The GA signaling pathway only plays a subsidiary role for flowering. However, the GA signaling pathway predominated for flowering under LD.
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Chrysanthemum/metabolismo , Flores/metabolismo , Giberelinas/metabolismo , Fotoperíodo , Transdução de Sinais , Chrysanthemum/genética , Chrysanthemum/fisiologia , Flores/genética , Flores/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
No studies have reported the isolation of serotype Salmonella Isangi from cases of salmonellosis in mainland China. We investigated an outbreak of foodborne disease with salmonella and collected the samples from the patients and surplus foods. Salmonella strains were isolated and the serotype was identified according to the Kauffmann-White scheme. The relatedness of the isolates was determined using pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). Antimicrobial susceptibility was conducted by the broth microdilution method. There were 74 diners in the case, 33 of which got ill, with an attack rate of 44.6% (33/74). A total of 24 samples were collected from the outbreak cases, six Salmonella Isangi strains were isolated and susceptible to all tested drugs. PFGE and WGS analysis suggested that the pathogen dissemination through a single or limited vector(s), the steamed fish and mixed food (fry spicy chicken, braised pork ribs, and goose leg), may be the source of infection or be cross-contaminated. We first report the characteristics of an outbreak and molecular strain relatedness of Salmonella Isangi in mainland China.
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Surtos de Doenças , Doenças Transmitidas por Alimentos/microbiologia , Intoxicação Alimentar por Salmonella/microbiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Adulto , Idoso , Técnicas de Tipagem Bacteriana , China/epidemiologia , Eletroforese em Gel de Campo Pulsado , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Polimorfismo de Nucleotídeo Único , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella enterica/classificação , Salmonella enterica/genética , Salmonella enterica/imunologia , Sorogrupo , Adulto JovemRESUMO
Autopolyploidy is widespread in higher plants and plays an important role in the process of evolution. The present study successfully induced autotetraploidys from Chrysanthemum lavandulifolium by colchicine. The plant morphology, genomic, transcriptomic, and epigenetic changes between tetraploid and diploid plants were investigated. Ligulate flower, tubular flower and leaves of tetraploid plants were greater than those of the diploid plants. Compared with diploid plants, the genome changed as a consequence of polyploidization in tetraploid plants, namely, 1.1% lost fragments and 1.6% novel fragments occurred. In addition, DNA methylation increased after genome doubling in tetraploid plants. Among 485 common transcript-derived fragments (TDFs), which existed in tetraploid and diploid progenitors, 62 fragments were detected as differentially expressed TDFs, 6.8% of TDFs exhibited up-regulated gene expression in the tetraploid plants and 6.0% exhibited down-regulation. The present study provides a reference for further studying the autopolyploidization role in the evolution of C. lavandulifolium. In conclusion, the autopolyploid C. lavandulifolium showed a global change in morphology, genome and gene expression compared with corresponding diploid.
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Chrysanthemum/genética , Genoma de Planta , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Chrysanthemum/anatomia & histologia , Metilação de DNA , DNA de Plantas/genética , DNA de Plantas/metabolismo , Epigênese Genética , Regulação da Expressão Gênica de Plantas , TetraploidiaRESUMO
Polyploidy is common among flowering plants, including the Asteraceae, a relatively recent angiosperm group. EST-SSRs were used to characterize polymorphism among 29 Chrysanthemum and Ajania spp. accessions of various ploidy levels. Most EST-SSR loci were readily transferable between the species, 29 accessions were separated into three groups in terms of the number of fragments. It inferred that the formation from tetraploid to hexaploid and from octoploid to decaploid may be a recent event, while from the diploid to the tetraploid may be an ancient one in the Chrysanthemum lineage. EST-SSR polymorphism was found and some transcripts containing an SSR were transcribed differently in the de novo autotetraploid C. nankingense and C. lavandulifolium than in their progenitor diploid. EST-SSR could provide a potential molecular basis of adaptation during evolution, while whole genome duplication has a major effect on the mutational dynamics of EST-SSR loci, which could also affect gene regulation.