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1.
Plant Mol Biol ; 113(1-3): 59-74, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37634200

RESUMO

Leaves are the primary photosynthetic organs, providing essential substances for tree growth. It is important to obtain an anatomical understanding and regulatory network analysis of leaf development. Here, we studied leaf development in Populus Nanlin895 along a development gradient from the newly emerged leaf from the shoot apex to the sixth leaf (L1 to L6) using anatomical observations and RNA-seq analysis. It indicated that mesophyll cells possess obvious vascular, palisade, and spongy tissue with distinct intercellular spaces after L3. Additionally, vacuoles fuse while epidermal cells expand to form pavement cells. RNA-seq analysis indicated that genes highly expressed in L1 and L2 were related to cell division and differentiation, while those highly expressed in L3 were enriched in photosynthesis. Therefore, we selected L1 and L3 to integrate ATAC-seq and RNA-seq and identified 735 differentially expressed genes (DEGs) with changes in chromatin accessibility regions within their promoters, of which 87 were transcription factors (TFs), such as ABI3VP1, AP-EREBP, MYB, NAC, and GRF. Motif enrichment analysis revealed potential regulatory functions for the DEGs through upstream TFs including TCP, bZIP, HD-ZIP, Dof, BBR-BPC, and MYB. Overall, our research provides a potential molecular foundation for regulatory network exploration in leaf development during photosynthesis establishment.

2.
Chemosphere ; 326: 138341, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36925008

RESUMO

The environmental and ecological consequences of nanoplastics (NPs) draw increasing research interests and social concerns. However, the in situ and real-time detection of NPs from living organisms and transferring media remains as a major technical obstacle for scientific investigation. Herein we report a novel time-gated imaging (TGI) strategy capable of real-time visualizing the intake of NPs by an individual living organism, which is based on the polystyrene NPs labelled with lanthanide up-conversion luminescence. The limit of detection (LOD) of the TGI apparatus was 600 pg (SNR = 3) in a field of view of 2.4 × 3.8 mm. Taking Daphnia magna as the aquatic model, we investigated the dynamics of uptake and accumulation of NPs (500 µg/L) for 24 h, and the subsequent excretion process (in clean medium) for 48 h, and quantitively analyzed the distribution and the overall mass of NPs deposited in D. magna. The uptake of NPs via filter-feeding occurred in a few minutes, whereas a longer accumulation was found, in a timescale of several hours. And similar behaviors (bi-phase elimination) were also seen in the excretion, indicating the migration of NPs into the circulatory system. The average mass of NPs accumulated in an individual D. magna was ∼12 ng after 24 h exposure, indicating that D. magna as a filter feeder tends to retain NPs. The observed NPs accumulation in D. magna exemplifies the potential risk of aquatic ecosystem on exposure to NP contamination.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Daphnia , Poliestirenos , Ecossistema , Luminescência , Imagem Óptica , Poluentes Químicos da Água/toxicidade
3.
Theor Appl Genet ; 136(3): 47, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36912930

RESUMO

KEY MESSAGE: Plastidial α-glucan phosphorylase is a key factor that cooperates with plastidial disproportionating enzyme to control short maltooligosaccharide mobilization during the initiation process of starch molecule synthesis in developing rice endosperm. Storage starch synthesis is essential for grain filling. However, little is known about how cereal endosperm controls starch synthesis initiation. One of core events for starch synthesis initiation is short maltooligosaccharide (MOS) mobilization consisting of long MOS primer production and excess MOS breakdown. By mutant analyses and biochemical investigations, we present here functional identifications of plastidial α-glucan phosphorylase (Pho1) and disproportionating enzyme (DPE1) during starch synthesis initiation in rice (Oryza sativa) endosperm. Pho1 deficiency impaired MOS mobilization, triggering short MOS accumulation and starch synthesis reduction during early seed development. The mutant seeds differed significantly in MOS level and starch content at 15 days after flowering and exhibited diverse endosperm phenotypes during mid-late seed development: ranging from pseudonormal to shrunken (Shr), severely or excessively Shr. The level of DPE1 was almost normal in the PN seeds but significantly reduced in the Shr seeds. Overexpression of DPE1 in pho1 resulted in plump seeds only. DPE1 deficiency had no obvious effects on MOS mobilization. Knockout of DPE1 in pho1 completely blocked MOS mobilization, resulting in severely and excessively Shr seeds only. These findings show that Pho1 cooperates with DPE1 to control short MOS mobilization during starch synthesis initiation in rice endosperm.


Assuntos
Endosperma , Oryza , Endosperma/genética , Endosperma/metabolismo , Oryza/metabolismo , Fosforilases/genética , Fosforilases/metabolismo , Amido/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Planta ; 255(5): 101, 2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35397691

RESUMO

MAIN CONCLUSION: PdeHCA2 regulates the transition from primary to secondary growth, plant architecture, and affects photosynthesis by targeting PdeBRC1 and controlling the anatomy of the mesophyll, and intercellular space, respectively. Branching, secondary growth, and photosynthesis are vital developmental processes of woody plants that determine plant architecture and timber yield. However, the mechanisms underlying these processes are unknown. Here, we report that the Populus transcription factor High Cambium Activity 2 (PdeHCA2) plays a role in the transition from primary to secondary growth, vascular development, and branching. In Populus, PdeHCA2 is expressed in undifferentiated provascular cells during primary growth, in phloem cells during secondary growth, and in leaf veins, which is different from the expression pattern of its homolog in Arabidopsis. Overexpression of PdeHCA2 has pleiotropic effects on shoot and leaf development; overexpression lines showed delayed growth of shoots and leaves, reduced photosynthesis, and abnormal shoot branching. In addition, auxin-, cytokinin-, and photosynthesis-related genes were differentially regulated in these lines. Electrophoretic mobility shift assays and transcriptome analysis indicated that PdeHCA2 directly up-regulates the expression of BRANCHED1 and the MADS-box gene PdeAGL9, which regulate plant architecture, by binding to cis-elements in the promoters of these genes. Taken together, our findings suggest that HCA2 regulates several processes in woody plants including vascular development, photosynthesis, and branching by affecting the proliferation and differentiation of parenchyma cells.


Assuntos
Arabidopsis , Populus , Arabidopsis/metabolismo , Biomassa , Câmbio , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/metabolismo
5.
J Phys Chem B ; 126(14): 2669-2676, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35377647

RESUMO

Carotenoid (Car) quenching chlorophyll triplet state (3Chl a*), an unwanted photosensitizer yielding harmful reactive oxygen species, is crucial for the survival of oxygenic photosynthetic organisms. For the major light-harvesting complex of photosystem II (LHCII) in isolated form, 3Chl a* is deactivated via sub-nanosecond Chl-to-Car triplet excitation energy transfer by lutein in the central domain of LHCII; however, the mechanistic difference from LHCII in vivo remains to be explored. To investigate the intrinsic Car-photoprotection properties of LHCII in a bio-mimicking circumstance, we reconstituted trimeric spinach LHCII into the discoidal membrane of nanosize made from l-α-phosphatidylcholine and examined the triplet excited dynamics. Time-resolved optical absorption combined with circular dichroism spectroscopies revealed that, with reference to LHCII in buffer, LHCII in the membrane nanodisc shows appreciable conformational variation in the neoxanthin and the Lut621 domains and in the Chl a-terminal cluster owing to the lipid-protein interactions, which, in turn, alters the triplet population of Lut620 and Lut621 and their partition. Importantly, the unquenched 3Chl a* population in the complex was reduced by 60%, indicating that LHCII in the membrane adopts a conformation that is optimized for the alleviation of photoinhibition.


Assuntos
Clorofila , Complexos de Proteínas Captadores de Luz , Spinacia oleracea , Carotenoides/metabolismo , Clorofila/metabolismo , Proteínas de Ligação à Clorofila/metabolismo , Transferência de Energia/fisiologia , Complexos de Proteínas Captadores de Luz/metabolismo , Lipídeos , Luteína/metabolismo , Nanopartículas , Complexo de Proteína do Fotossistema II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Spinacia oleracea/metabolismo , Tilacoides/metabolismo
6.
Psychiatry Res ; 307: 114326, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896845

RESUMO

BACKGROUND: We aimed to characterize gut microbial alterations in depressed patients with bipolar disorder (BD) following quetiapine monotherapy and explored its potential for disease diagnosis and outcome prediction. METHODS: Fecal samples were obtained from 60 healthy individuals and 62 patients in acute depressive episodes. All patients received one-month quetiapine treatment after enrollment. The structure of gut microbiota was measured with metagenomic sequencing, and its correlation with clinical profiles and brain function as indicated by resting-state functional magnetic resonance imaging was analyzed. Random forest models based on bacterial species were constructed to distinguish patients from controls, and responders from non-responders, respectively. RESULTS: BD patients displayed specific alterations in gut microbial diversity and composition. Quetiapine treatment increased the diversity of microbial communities and changed the composition. The abundance of Clostridium bartlettii was negatively associated with age, baseline depression severity, while positively associated with spontaneous neural oscillation in the hippocampus. Tree-based classification models for (1) patients and controls and (2) responders and non-responders showed an area under the curve of 0.733 and 0.800, respectively. CONCLUSION: Our findings add new evidence to the existing literature regarding gut dysbiosis in BD and reveal the potential of microbe-based biomarkers for disease diagnosis and treatment outcome prediction.


Assuntos
Transtorno Bipolar , Microbioma Gastrointestinal , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Disbiose , Microbioma Gastrointestinal/genética , Humanos , Metagenômica , Resultado do Tratamento
7.
BMC Endocr Disord ; 21(1): 193, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563184

RESUMO

BACKGROUND: Variants of chromodomain helicase DNA binding protein 7 (CHD7) gene are commonly associated with Kallmann syndrome (KS) and account for 5-6% of idiopathic hypogonadotropic hypogonadism (IHH) cases. Here we report a novel mutation of CHD7 gene in a patient with KS, which may contribute to the better understanding of KS. CASE PRESENTATION: A 29-year-old male patient with KS and a chief complaint of delayed puberty for 13 years (Tanner B Stage< 4) was admitted to the Department of Endocrinology of the First Affiliated Hospital of Zhejiang University (Hangzhou, China) in September 2019. Dual-energy X-ray absorptiometry (DEXA) showed low bone density in both lumbar spine (L1 ~ L5 mean Z-score - 3.0) and femoral neck (Z-score - 2.7). Dynamic contrast-enhanced magnetic resonance imaging (MRI) of pituitary and contrast-enhanced computed tomography (CT) showed no abnormal findings. Ophthalmological evaluation showed that his both eyes showed exotropia, and no sight loss was noted. Heterozygous c.1619G > T mutation of TCD7 gene (p.G4856V) was detected, whereas none of his family members had this mutation. Human chorionic gonadotropin (HCG) and human menopausal gonadotropin (HMG) were injected for three times/week to treat idiopathic hypogonadotropic hypogonadism (IHH). After several months of therapy, the patient's health condition improved. His testicles became larger, and his secondary sexual characteristics improved after treatment. CONCLUSION: Exploration of the novel splice-site mutation of CHD7 may further our current understanding of KS.


Assuntos
DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Síndrome de Kallmann/genética , Mutação de Sentido Incorreto , Adulto , China , Análise Mutacional de DNA , Heterozigoto , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/genética , Hipogonadismo/terapia , Síndrome de Kallmann/complicações , Síndrome de Kallmann/diagnóstico , Síndrome de Kallmann/terapia , Imageamento por Ressonância Magnética , Masculino , Polimorfismo de Nucleotídeo Único , Puberdade Tardia/diagnóstico , Puberdade Tardia/etiologia , Puberdade Tardia/genética , Puberdade Tardia/terapia , Tomografia Computadorizada por Raios X
8.
Aging (Albany NY) ; 12(13): 13365-13387, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651957

RESUMO

In this study, we investigated the mechanisms underlying the altered hepatic glucose metabolism and enhanced diabetes risk in individuals with the TCF7L2 rs290487 C allele. Analysis of 195 cirrhotic patients revealed a higher insulin resistance index and incidence of hepatogenous diabetes in patients with the rs290487 C/C genotype compared to those with the C/T or T/T genotype. The in vitro experiments using targeted mutant PLC-PRF-5 cell line showed that cells with the rs290487 C/C genotype (C/C cells) had higher glucose production, lower glucose uptake, and lower TCF7L2 mRNA and protein levels than those with the C/T genotype (C/T cells). Integrated multi-omics analysis of ChIP-seq, ATAC-seq, RNA-seq, and metabolomics data showed genome-wide alterations in the DNA binding affinity of TCF7L2 in the C/C cells, including gain (e.g., PFKP and PPARGC1A) and loss (e.g., PGK1 and PGM1) of binding sites in several glucose metabolism-related genes. These allele-specific changes in transcriptional regulation lead to increased expression of gluconeogenesis-related genes (PCK1, G6PC and PPARGC1A) and their downstream metabolites (oxaloacetate and ß-D-fructose 2,6-bisphosphate). These findings demonstrate that the TCF7L2 rs290487 C allele enhances gluconeogenesis through allele-specific changes in transcription and chromatin binding.


Assuntos
Diabetes Mellitus Tipo 2/genética , Gluconeogênese/genética , Glucose/metabolismo , Cirrose Hepática/complicações , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Adulto , Alelos , Cromatina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Incidência , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metabolômica , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , RNA-Seq , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo
9.
New Phytol ; 228(1): 163-178, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32464682

RESUMO

Transport and homeostasis of transition metals in chloroplasts, which are accurately regulated to ensure supply and to prevent toxicity induced by these metals, are thus crucial for chloroplast function and photosynthetic performance. However, the mechanisms that maintain the balance of transition metals in chloroplasts remain largely unknown. We have characterized an albino-revertible green 1 (arg1) rice mutant. ARG1 encodes an evolutionarily conserved protein belonging to the ATP-binding cassette (ABC) transporter family. Protoplast transfection and immunogold-labelling assays showed that ARG1 is localized in the envelopes and thylakoid membranes of chloroplasts. Measurements of metal contents, metal transport, physiological and transcriptome changes revealed that ARG1 modulates cobalt (Co) and nickel (Ni) transport and homeostasis in chloroplasts to prevent excessive Co and Ni from competing with essential metal cofactors in chlorophyll and metal-binding proteins acting in photosynthesis. Natural allelic variation in ARG1 between indica and temperate japonica subspecies of rice is coupled with their different capabilities for Co transport and Co content within chloroplasts. This variation underpins the different photosynthetic capabilities in these subspecies. Our findings link the function of the ARG1 transporter to photosynthesis, and potentially facilitate breeding of rice cultivars with improved Co homeostasis and consequently improved photosynthetic performance.


Assuntos
Oryza , Transportadores de Cassetes de Ligação de ATP/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cobalto/metabolismo , Homeostase , Níquel/metabolismo , Níquel/toxicidade , Oryza/genética , Fotossíntese , Melhoramento Vegetal
10.
Mol Med Rep ; 22(1): 165-174, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32319638

RESUMO

Hyperglycemia contributes to the excessive proliferation and migration of vascular smooth muscle cells (VSMC), which are closely associated with atherosclerosis. MicroRNAs (miRNAs/miRs) constitute a novel class of gene regulators, which have important roles in various pathological conditions. The aim of the present study was to identify miRNAs involved in the high glucose (HG)­induced VSMC phenotype switch, and to investigate the underlying mechanism. miRNA sequencing and reverse transcription­quantitative PCR results indicated that inhibition of miR­125a expression increased the migration and proliferation of VSMCs following HG exposure, whereas the overexpression of miR­125a abrogated this effect. Furthermore, dual­luciferase reporter assay results identified that 3­hydroxy­3-methyglutaryl­coA reductase (HMGCR), one of the key enzymes in the mevalonate signaling pathway, is a target of miR­125a. Moreover, HMGCR knockdown, similarly to miR­125a overexpression, suppressed HG­induced VSMC proliferation and migration. These results were consistent with those from the miRNA target prediction programs. Using a rat model of streptozotocin­induced diabetes mellitus, it was demonstrated that miR­125a expression was gradually downregulated, and that the expressions of key enzymes in the mevalonate signaling pathway in the aortic media were dysregulated after several weeks. In addition, it was found that HG­induced excessive activation of the mevalonate signaling pathway in VSMCs was suppressed following transfection with a miR­125a mimic. Therefore, the present results suggest that decreased miR­125a expression contributed to HG­induced VSMC proliferation and migration via the upregulation of HMGCR expression. Thus, miR­125a­mediated regulation of the mevalonate signaling pathway may be associated with atherosclerosis.


Assuntos
Hiperglicemia/genética , Ácido Mevalônico/metabolismo , MicroRNAs/genética , Músculo Liso Vascular/citologia , Transdução de Sinais , Animais , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Glucose/metabolismo , Hiperglicemia/metabolismo , Masculino , Músculo Liso Vascular/metabolismo , Ratos Sprague-Dawley
11.
J Biol Chem ; 294(32): 12112-12121, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31217279

RESUMO

Conjugated equine estrogens (CEEs), whose brand name is Premarin, are widely used as a hormone-replacement therapy (HRT) drug to manage postmenopausal symptoms in women. Extracted from pregnant mare urine, CEEs are composed of nearly a dozen estrogens existing in an inactive sulfated form. To determine whether the hepatic steroid sulfatase (STS) is a key contributor to the efficacy of CEEs in HRT, we performed estrogen-responsive element (ERE) reporter gene assay, real-time PCR, and UPLC-MS/MS to assess the STS-dependent and inflammation-responsive estrogenic activity of CEEs in HepG2 cells and human primary hepatocytes. Using liver-specific STS-expressing transgenic mice, we also evaluated the effect of STS on the estrogenic activity of CEEs in vivo We observed that CEEs induce activity of the ERE reporter gene in an STS-dependent manner and that genetic or pharmacological inhibition of STS attenuates CEE estrogenic activity. In hepatocytes, inflammation enhanced CEE estrogenic activity by inducing STS gene expression. The inflammation-responsive estrogenic activity of CEEs, in turn, attenuated inflammation through the anti-inflammatory activity of the active estrogens. In vivo, transgenic mice with liver-specific STS expression exhibited markedly increased sensitivity to CEE-induced estrogenic activity in the uterus resulting from increased levels of liver-derived and circulating estrogens. Our results reveal a critical role of hepatic STS in mediating the hormone-replacing activity of CEEs. We propose that caution needs to be applied when Premarin is used in patients with chronic inflammatory liver diseases because such patients may have heightened sensitivity to CEEs due to the inflammatory induction of STS activity.


Assuntos
Estrogênios Conjugados (USP)/metabolismo , Esteril-Sulfatase/metabolismo , Animais , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios Conjugados (USP)/análise , Estrogênios Conjugados (USP)/farmacologia , Feminino , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Cavalos , Humanos , Inflamação/metabolismo , Inflamação/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Esteril-Sulfatase/antagonistas & inibidores , Esteril-Sulfatase/genética , Espectrometria de Massas em Tandem , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/patologia
12.
Environ Sci Technol ; 53(3): 1471-1481, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30605315

RESUMO

This work reports the in vivo uptake and translocation of PNPs in the one-year grown terrestrial plant, Murraya exotica ( M. exotica), as investigated by two-photon excitation and time-resolved (TPE-TR) optical imaging with a large field of view (FOV, 32 × 32 mm2) in a noninvasive and real-time manner. The PNPs (⟨ Rh⟩ = 12 ± 4.5 nm) synthesized from poly(styrene- co-maleic anhydride) (SMA) were Eu-luminescence labeled (λL ≈ 617 nm). On exposing the roots of living M. exotica plants to the colloidal suspension of SMA PNPs at different concentrations, the spatiotemporal evolution of SMA PNPs along plant stems (60 mm in length) were monitored by TPE-TR imaging, which rendered rich information on the uptake and translocation of PNPs without any interference from the autofluorescence of the plant tissues. The TPE-TR imaging combined with the high-resolution anatomy revealed an intercell-wall route in the lignified epidermis of M. exotica plants for SMA PNP uptake and translocation, as well as the similar accumulation kinetics at different positions along the plant stems. We modeled the accumulation kinetics with Gaussian distribution to account for the trapping probability of a SMA PNP by the lignified cell walls, allowing the statistical parameters, the average trapping time ( tm) and its variance (σ), to be derived for the quantification of the PNP accumulation in individual plants. The TPE-TR imaging and the analysis protocols established herein will be helpful in exploring the mechanism of plant-PNP interaction under physiological condition.


Assuntos
Murraya , Nanopartículas , Anidridos Maleicos , Imagem Óptica , Estireno
13.
Plant Biotechnol J ; 17(1): 206-219, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29851301

RESUMO

The Populus shoot undergoes primary growth (longitudinal growth) followed by secondary growth (radial growth), which produces biomass that is an important source of energy worldwide. We adopted joint PacBio Iso-Seq and RNA-seq analysis to identify differentially expressed transcripts along a developmental gradient from the shoot apex to the fifth internode of Populus Nanlin895. We obtained 87 150 full-length transcripts, including 2081 new isoforms and 62 058 new alternatively spliced isoforms, most of which were produced by intron retention, that were used to update the Populus annotation. Among these novel isoforms, there are 1187 long non-coding RNAs and 356 fusion genes. Using this annotation, we found 15 838 differentially expressed transcripts along the shoot developmental gradient, of which 1216 were transcription factors (TFs). Only a few of these genes were reported previously. The differential expression of these TFs suggests that they may play important roles in primary and secondary growth. AP2, ARF, YABBY and GRF TFs are highly expressed in the apex, whereas NAC, bZIP, PLATZ and HSF TFs are likely to be important for secondary growth. Overall, our findings provide evidence that long-read sequencing can complement short-read sequencing for cataloguing and quantifying eukaryotic transcripts and increase our understanding of the vital and dynamic process of shoot development.


Assuntos
Caules de Planta/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento , Transcriptoma , Processamento Alternativo/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Filogenia , Caules de Planta/anatomia & histologia , Caules de Planta/metabolismo , Populus/genética , Populus/metabolismo , RNA Longo não Codificante/genética , Transcriptoma/genética
14.
J Cell Mol Med ; 22(12): 6167-6175, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30338914

RESUMO

The aberrant expression of Pknox1 is associated with hepatic glucose and lipid dysmetabolism status of type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD). However, the underlying mechanism causing Pknox1 overexpression in this pathological status remains unclear. By using miRNA target prediction programs, we found that the 3'-UTR of the Pknox1 mRNA sequence contains highly conserved target sites of miR-17 family. In a rat model of streptozotocin and high-fat diet-induced T2DM and NAFLD complication, the increased hepatic expression of Pknox1 was consistent with decreased expressions of miR-17 family, especially miR-17 and miR-20a. Furthermore, an inverse correlation was observed between Pknox1 and miR-17 and miR-20a in free fatty acids-induced hepatocyte steatosis. Dual-luciferase reporter assay further showed that Pknox1 was a valid target gene of miR-17 family. The ectopic expression of miR-17 or miR-20a could markedly suppress Pknox1 expression in hepatocytes. MiR-17 or miR-20a overexpression also resulted in significantly enhanced insulin sensitivity and reduced hepatocyte steatosis in HepG2 and L02 cells, which were determined by altered phosphorylation on insulin receptor signaling pathway proteins and decreased intracellular triglyceride and lipid accumulation, respectively. These data implicate the upregulated hepatic expression of Pknox1 in T2DM complicated with NAFLD may be caused by the reduced expression of miR-17 family, indicating that developing miRNA-mediated regulation strategies on Pknox1 may provide new therapeutic options for metabolic disease.


Assuntos
Diabetes Mellitus Tipo 2/genética , Fígado Gorduroso/genética , Proteínas de Homeodomínio/genética , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/genética , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Fígado Gorduroso/complicações , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Insulina/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Transdução de Sinais/genética
15.
Life Sci ; 208: 201-207, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30030064

RESUMO

AIMS: Type 2 diabetes mellitus (T2DM), with non-alcoholic fatty liver disease (NAFLD) complication, may aggravate the disturbance of metabolism, increase the risk of non-alcoholic steatohepatitis, and promote the progress of liver fibrosis. Therefore, early detection of NAFLD in T2DM patients is critical in avoiding the adverse effects of the complication. This study aimed to identify circulating miRNAs for early diagnosis of the complication. MATERIALS AND METHODS: Plasma miRNA expression profiles of T2DM patients complicated with or without NAFLD were examined by miRNA array analysis and then were validated by qRT-PCR. A new index for prediction the presence of NAFLD was developed based on the result of multivariate logistic regression analysis. STZ and high fat diet were used for construction a rat model of T2DM complicated with NAFLD. KEY FINDINGS: Plasma miR-17, miR-20a, miR-20b, and miR-122 were up-regulated in T2DM patients with NAFLD complicated compared in those without NAFLD (P < 0.05). Moreover, the data from the rat model further showed that the above miRNAs were more sensitive than traditional serological markers for predicting the complication. Meanwhile, in order to improve the diagnostic accuracy, we try to construct an AUC by using the new index, 24.852 × WHR-1.121 × miR122 + 1.988 × LDL-21.838, which was significantly higher than a chance assignment (asymptotic significance P < 0.001) for predicting the presence of NAFLD. SIGNIFICANCE: Plasma miRNAs and the new index involving WHR, LDL, and miR-122 are potential novel tools for the early diagnosis and risk estimation of NAFLD in T2DM patients.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/complicações , Regulação da Expressão Gênica , MicroRNAs/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Animais , Estudos de Casos e Controles , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Prognóstico , Ratos , Ratos Wistar
16.
New Phytol ; 213(1): 300-313, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27401059

RESUMO

Here, we compared the development of dark- and light-grown Chinese fir (Cunninghamia lanceolata) cotyledons, which synthesize chlorophyll in the dark, representing a different phenomenon from angiosperm model plants. We determined that the grana lamellar membranes were well developed in both chloroplasts and etiochloroplasts. The accumulation of thylakoid membrane protein complexes was similar between chloroplasts and etiochloroplasts. Measurement of chlorophyll fluorescence parameters indicated that photosystem II (PSII) had low photosynthetic activities, whereas the photosystem I (PSI)-driven cyclic electron flow (CEF) rate exceeded the rate of PSII-mediated photon harvesting in etiochloroplasts. Analysis of the protein contents in etiochloroplasts indicated that the light-harvesting complex II remained mostly in its monomeric conformation. The ferredoxin NADP+ oxidoreductase and NADH dehydrogenase-like complexes were relatively abundantly expressed in etiochloroplasts for Chinese fir. Our transcriptome analysis contributes a global expression database for Chinese fir cotyledons, providing background information on the regulatory mechanisms of different genes involved in the development of dark- and light-grown cotyledons. In conclusion, we provide a novel description of the early developmental status of the light-dependent and light-independent photosynthetic apparatuses in gymnosperms.


Assuntos
Cunninghamia/fisiologia , Cunninghamia/efeitos da radiação , Luz , Fotossíntese/efeitos da radiação , Clorofila/metabolismo , Cotilédone/metabolismo , Cotilédone/efeitos da radiação , Cunninghamia/genética , Escuridão , Transporte de Elétrons/efeitos da radiação , Fluorescência , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Complexos Multiproteicos/metabolismo , Fosforilação/efeitos da radiação , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Plastídeos/metabolismo , Plastídeos/ultraestrutura , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação
17.
Sci Rep ; 6: 30686, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27465520

RESUMO

This study aimed to investigate the possible association between diabetes susceptibility gene transcription factor 7-like 2 (TCF7L2) and gestational diabetes mellitus (GDM) in a Chinese Han population. A total of 556 GDM patients and 500 Non-GDM were included. Eighteen single nucleotide polymorphisms (SNPs) were evaluated. Fifteen tag SNPs were selected from HapMap CHB database with a minor allele frequency of >0.2 and r(2) of >0.8. Three additional SNPs were also chosen because these SNPs are associated with type 2 diabetes in East Asians. TCF7L2 rs290487, rs6585194, and rs7094463 polymorphisms were found to be significantly associated with GDM. In multivariate analysis, rs290487 genetic variation (OR = 2.686 per each C allele, P = 0.002), pre-BMI > 24 kg/m(2) (OR = 1.592, P = 0.018), age > 25 years (OR = 1.780, P = 0.012) and LDL-C > 3.6 mmol/L (OR = 2.034, P = 0.009) were identified as independent risk factors of GDM, rs7094463 genetic variation (OR = 0.429 per each G allele, P = 0.005) was identified as independent protect factor of GDM. This finding suggests that TCF7L2 rs290487, and rs7094463 were a potential clinical value for the prediction of GDM.


Assuntos
Diabetes Gestacional/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Povo Asiático , Feminino , Estudos de Associação Genética , Humanos , Gravidez
18.
Heart Rhythm ; 13(10): 2040-7, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27374309

RESUMO

BACKGROUND: Recurrence of atrial fibrillation (AF) after ablation is still high. Perindopril plays an essential role in AF induction and maintenance. OBJECTIVE: We aimed to prove that perindopril (8 mg) could prevent recurrence after pulmonary vein isolation. METHODS: Patients with paroxysmal AF who received radiofrequency ablation were randomized to a 3-month course of perindopril 8 mg once daily (perindopril group) or placebo (placebo group). Angiotensin-II (Ang-II) therapy and standard transthoracic echocardiography were performed. All 256 patients with paroxysmal AF who received radiofrequency ablation were randomized. And we followed them for complete 1 year. The 3-month recurrence and the 1-year recurrence were compared between the 2 groups. RESULTS: The 3-month recurrence of AF was observed in 33 (26.19%) of 126 patients in the placebo group vs 19 (14.62%) of 130 patients who received perindopril 8 mg once daily (χ2, P = .021). One-year recurrence of AF was observed in 36 (28.5%) of 126 patients in the placebo group as compared with 21 (16.2%) of 130 patients who received perindopril after 1 year (P = .017). The κ value was 0.94 in the control group (P < .001) and 0.96 in the perindopril group (P < .001) between 3-month and 1-year recurrence. The Ang-II level was related to the left atrial distance with the reduction in AF recurrence (r = 0.17, P = .005 at 3 months; r = 0.25, P < .001 at 1 year). CONCLUSION: Perindopril is an effective and safe treatment for the prevention of AF recurrence after radiofrequency catheter ablation. This effect seems to be strongly associated with a significant decrease in Ang-II level and left atrial distance.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Perindopril , Complicações Pós-Operatórias/prevenção & controle , Veias Pulmonares/cirurgia , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perindopril/administração & dosagem , Perindopril/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Prevenção Secundária/métodos , Resultado do Tratamento
19.
Sci Rep ; 6: 24859, 2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-27108846

RESUMO

To evaluate the role of TCF7L2, a key regulator of glucose homeostasis, in estradiol (E2) and progesterone (P4)-modulated glucose metabolism, mouse insulinoma cells (MIN6) and human liver cancer cells (hepG2 and HUH7) were treated with physiological concentrations of E2 or P4 in the up- and down-regulation of TCF7L2. Insulin/proinsulin secretion was measured in MIN6 cells, while glucose uptake and production were evaluated in liver cancer cells. E2 increased insulin/proinsulin secretion under both basal and stimulated conditions, whereas P4 increased insulin/proinsulin secretion only under glucose-stimulated conditions. An antagonistic effect, possibly concentration-dependent, of E2 and P4 on the regulation of islet glucose metabolism was observed. After E2 or P4 treatment, secretion of insulin/proinsulin was positively correlated with TCF7L2 protein expression. When TCF7L2 was silenced, E2- or P4-promoted insulin/proinsulin secretion was significantly weakened. Under glucotoxicity conditions, overexpression of TCF7L2 increased insulin secretion and processing. In liver cancer cells, E2 or P4 exposure elevated TCF7L2 expression, enhanced the activity of insulin signaling (pAKT/pGSK), reduced PEPCK expression, subsequently increased insulin-stimulated glucose uptake, and decreased glucose production. Silencing TCF7L2 eliminated effects of E2 or P4. In conclusion, TCF7L2 regulates E2- or P4-modulated islet and hepatic glucose metabolism. The results have implications for glucose homeostasis in pregnancy.


Assuntos
Estradiol/metabolismo , Glucose/metabolismo , Homeostase , Ilhotas Pancreáticas/metabolismo , Fígado/metabolismo , Progesterona/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Animais , Linhagem Celular , Humanos , Camundongos
20.
J Zhejiang Univ Sci B ; 16(11): 963-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26537215

RESUMO

Congenital X-linked adrenal hypoplasia (AHC) is a rare disease characterized by primary adrenal insufficiency before adolescence and by hypogonadotropic hypogonadism (HHG) during adolescence. In this paper, we present a Chinese family with AHC. Two brothers, misdiagnosed with adrenal insufficiency of unknown etiology at the age of 9, were correctly diagnosed with AHC when delayed puberty, HHG, and testicular defects were observed. We investigated the clinical features and identified the dosage-sensitive sex reversal AHC critical region of the X chromosome gene 1 (DAX-1) mutation in this kindred. Direct sequencing of the DAX-1 gene revealed that the two siblings have a novel mutation (1268delA) of which their mother is a heterozygous carrier. This mutation causes a frameshift and a premature stop codon at position 436, encoding a truncated protein. It is important to increase knowledge of the mutational spectrum in genes related to this disease, linking phenotype to genotype.


Assuntos
Insuficiência Adrenal/genética , Receptor Nuclear Órfão DAX-1/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Mutação , Adulto , Humanos , Hipoadrenocorticismo Familiar , Masculino
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