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1.
World J Surg Oncol ; 17(1): 152, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31472673

RESUMO

BACKGROUND: In some malignant tumors, a high neutrophil-to-lymphocyte ratio (NLR) is connected with unfavorable prognosis. Nevertheless, the prognostic value of the NLR in gliomas remains disputed. The clinical significance of the NLR in gliomas was investigated in our study. METHODS: The databases, PubMed, Embase, and the Cochrane Library, were searched using words like "glioma," "glioblastoma," "neutrophil-to-lymphocyte ratio," and others through May 2019. We evaluated the significance of NLR on overall survival (OS) of patients with gliomas in our study. RESULTS: Finally, 16 cohorts with 2275 patients were analyzed. The pooled analysis revealed that an elevated NLR was connected with unfavorable OS (hazards ratio (HR): 1.43, 95% confidence interval (CI): 1.27-1.62) outcomes of patients with gliomas. CONCLUSION: A high NLR can be considered a high-risk prognostic factor in gliomas, and more adjuvant chemotherapy should be recommended for high-risk patients.

2.
J Bioenerg Biomembr ; 51(4): 291-300, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31273531

RESUMO

To understand the role of microRNA-141 (miR-141) in hypoxia/reoxygenation (H/R)-induced PC12 cell injury via modulation of Keap1/Nrf2 signaling pathway. PC12 cells were divided into Control, H/R, H/R + miR-141 mimics, H/R + NC, H/R + miR-141 inhibitor, H/R + siKeap1 and H/R + miR-141 inhibitors+siKeap1 groups. The expression of miR-141 and Keap1/Nrf2 pathway was measured by qRT-PCR and western blotting, cell viability evaluated by MTT assay while cell apoptosis tested by flow cytometry. Besides, MDA (malondialdehyde), SOD (Super Oxide Dismutase) and LDH (lactate dehydrogenase) levels were determined. DCFH-DA and JC-1 staining were used to measure ROS and mitochondrial membrane potential (MMP) respectively. Compared with Controls, PC12 cells induced by H/R exhibited decreased cell viability and increased cell apoptosis rate, with elevated MDA, LDH and ROS and reduced SOD levels; and meanwhile, MMP and miR-141 expression were declined, whereas cytoplasmic Nrf2 levels were enhanced with the downregulated nuclear Nrf2 level (all P < 0.05). However, these cells treated with miR-141 mimics and siKeap1 showed obvious improvement in H/R-induced cell injury, while miR-141 inhibitors presented significantly aggravated cell injury (both P < 0.05). Besides, siKeap1 can reverse the effect of miRNA-141 inhibitors on aggravating H/R-induced PC12 cell injury. miR-141-mediated Keap1/Nrf2 signaling pathway to promote cell viability, inhibit cell apoptosis and reduce oxidative stress of PC12 cells, thereby alleviating H/R-induced cell injury.

3.
Biomed Pharmacother ; 117: 109092, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203134

RESUMO

BACKGROUND: 17ß-Estradiol (E2) is a critical regulator of trophoblast function during pregnancy. Serum- and glucocorticoid-inducible kinase (SGK1) has been shown to regulate specific cellular targets downstream of E2. However, whether and how SGK1 directly mediates the regulatory effects of E2 on trophoblasts functions remain unknown. METHODS: SGK1 expression in human villous samples and serum E2 levels were measured in women with early pregnancy loss (EPL) and healthy pregnant women. The effect of E2 on SGK1 regulation was assessed using luciferase reporter gene assay and Chromatin Immunoprecipitation assay. The mediation of regulatory effects of E2 by SGK1 on trophoblast functions including cell viability, invasion and related signaling molecules such as B cell leukemia/lymphoma 6, E-cadherin, matrix metalloproteinase 2, α-ENaC, vascular endothelial growth factor, and the phosphorylation status of FOXO1 and AKT were evaluated in HTR8/SVneo cells transfected with SGK1 knockdown plasmid with/without E2 treatment. RESULTS: SGK1 protein levels in human villous samples and serum E2 levels were decreased in patients with EPL compared to controls. E2 (10 nM) increased SGK1 promoter activity directly through estrogen receptor. E2-activated SGK1 enhanced cell viability, invasion and downstream targets in trophoblast cells. SGK1 knockdown abrogated the above responses to E2 treatment. CONCLUSIONS: SGK1 mediates the effects of E2 on trophoblast viability and invasion, suggesting that SGK1 acts as a key node in regulating the cross-talk at the feto-maternal interface during the development of placenta and might be a potential therapeutic target for EPL.

4.
BMC Plant Biol ; 19(1): 124, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940071

RESUMO

BACKGROUND: Acetolactate synthase (ALS)-inhibiting herbicide tribenuron-methyl (TBM) is an efficient gametocide that can cause rapeseed (Brassica napus L.) to become male sterile and outcrossing. To find the reason the TBM treatment leads to male sterility, an integrated study using cytological, physiological, and transcriptomic methods was conducted. RESULTS: Some temporary symptoms, including the discoloration of young leaves and a short halt of raceme elongation, were observed in the rapeseed plants exposed to TBM at an application rate of 1 µg per plant. Both chloroplasts in young leaves and plastids in anthers were deformed. TBM also reduced the leaf photosynthetic rate and the contents of chlorophyll, soluble sugar and pyruvate. Both the tapetal cells and uni-nucleate microspores in the treated plants showed large autophagic vacuoles, and the tissue degenerated quickly. A transcriptomic comparison with the control identified 200 upregulated and 163 downregulated differential expression genes in the small flower buds of the TBM treatment. The genes encoding functionally important proteins, including glucan endo-1,3-beta-glucosidase A6, QUARTET3 (QRT3), ARABIDOPSIS ANTHER 7 (ATA7), non-specific lipid-transfer protein LTP11 and LTP12, histone-lysine N-methyltransferase ATXR6, spermidine coumaroyl-CoA acyltransferase (SCT), and photosystem II reaction centre protein psbB, were downregulated by TBM exposure. Some important genes encoding autophagy-related protein ATG8a and metabolic detoxification related proteins, including DTX1, DTX6, DTX35, cytosolic sulfotransferase SOT12, and six members of glutathione S-transferase, were upregulated. In addition, several genes related to hormone stimulus, such as 1-aminocyclopropane-1-carboxylate synthase 8 (ACS8), ethylene-responsive factor ERF1A, ERF1, ERF71, CRF6, and RAP2-3, were also upregulated. The transcriptional regulation is in accordance with the functional abnormalities of pollen wall formation, lipid metabolism, chloroplast structure, ethylene generation, cell cycle, and tissue autophagy. CONCLUSION: The results suggested that except for ALS, the metabolic pathways related to lipid metabolism, pollen exine formation, photosynthesis and hormone response are associated with male sterility induced by TBM. The results provide new insight into the molecular mechanisms of inducing male sterility by sulfonylurea.


Assuntos
Acetolactato Sintase/antagonistas & inibidores , Sulfonatos de Arila/farmacologia , Brassica napus/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Herbicidas/farmacologia , Infertilidade das Plantas/efeitos dos fármacos , Acetolactato Sintase/metabolismo , Brassica napus/enzimologia , Brassica napus/fisiologia , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/fisiologia , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/metabolismo
5.
Sheng Li Xue Bao ; 71(1): 22-32, 2019 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-30778501

RESUMO

Bipedalism (using only two legs for walking) and having the capability to use tools have long been considered characteristic features that differentiate human beings from animals. Being able to walk upright freed up human hands, allowing us to reach, grasp, carry food, make and use tools, which greatly increased the survivability of our ancestors. Hand actions not only involve muscles and joints to execute actions but also require computations in the brain to analyze the visual environment and select the appropriate action, as well as formulate the action before execution and correct it in real-time during execution. Here, we review the behavioral and brain imaging research of human hand actions from a perspective of cognitive neuroscience. The review includes the research contents and methods of visually-guided action, existing theories, current debates, new evidence of existing theories, and the applications of action research in robotics and artificial intelligence.


Assuntos
Encéfalo/fisiologia , Neuroimagem , Desempenho Psicomotor , Encéfalo/diagnóstico por imagem , Mãos , Humanos
6.
Phytochemistry ; 159: 190-198, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30634081

RESUMO

Previously it has been shown that the caffeoyl coenzyme A O-methyltransferase (CCoAOMT) type enzyme PaF6OMT, synthesized by the liverwort Plagiochasma appendiculatum Lehm. & Lindenb., (Aytoniaceae), interacts preferentially with 6-OH flavones. To clarify the biochemistry and evolution of liverwort OMTs, a comparison was made between the nucleotide sequence and biological activity of PaF6OMT and those of three of its homologs MpOMT1 (from Marchantia paleacea Bertol., (Marchantiaceae)), MeOMT1 (Marchantia emarginata Reinw et al., (Marchantiaceae)) and HmOMT1 (Haplomitrium mnioides (Lindb.) Schust., (Haplomitriaceae)). The four genes shared >60% level of sequence identity with one another but a <20% level of similarity with typical CCoAOMT or CCoAOMT-like sequences; they clustered with genes encoding animal catechol methyltransferases. The recombinant OMTs recognized phenylpropanoids, flavonoids and coumarins as substrates, but not catechol. MpOMT1 and PaF6OMT exhibited some differences with respect to their substrate preference, and the key residues underlying this preference were identified using site-directed mutagenesis. The co-expression of MpOMT1 and the Arabidopsis thaliana gene encoding S-adenosyl-L-methionine synthase in Escherichia coli was shown to be an effective means of enhancing the production of the pharmacologically active compounds scopoletin and oroxylin A. Liverwort OMTs are thought likely to represent an ancestral out-group of bona fide higher plant CCoAOMTs in evolution and have the potential to be exploited for the production of methylated flavones and coumarins.


Assuntos
Hepatófitas/enzimologia , Metiltransferases/metabolismo , Sequência de Aminoácidos , Catálise , Proliferação de Células/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Genes de Plantas , Hepatófitas/classificação , Hepatófitas/genética , Metiltransferases/química , Metiltransferases/genética , Filogenia , Escopoletina/isolamento & purificação , Escopoletina/farmacologia , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Especificidade por Substrato
7.
Plant Physiol Biochem ; 136: 169-177, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30685696

RESUMO

Caffeoyl Coenzyme A 3-O-methyltransferases (CCoAOMTs) catalyze the transfer of a methyl group from S-adenosylmethionine (SAM) to a hydroxyl moiety. CCoAOMTs are important for the synthesis of lignin, which provides much of the rigidity required by tracheophytes to enable the long distance transport of water. So far, no CCoAOMTs has been characterized from the ancient tracheophytes ferns. Here, two genes, each encoding a CCoAOMT (and hence denoted PaCCoAOMT1 and PaCCoAOMT2), were isolated from the fern species Polypodiodes amoena. Sequence comparisons confirmed that the product of each gene resembled enzymes known to be associated with lignin synthesis in higher plants. When either of the genes was heterologously expressed in E. coli, the resulting recombinant protein was able to methylate caffeoyl CoA, along with a number of phenylpropanoids, flavones and flavonols containing two vicinal hydroxyl groups. Their in vitro conversion rate when presented with either caffeoyl CoA or certain flavonoids as substrate was comparable with that of the Medicago sativa MsCCoAOMT. Their constitutive expression in Arabidopsis thaliana boosted the plants' lignin content, but did not affect that of methylated flavonols, indicating that both PaCCoAOMTs contributed to lignin synthesis and that neither was able to methylate flavonols in planta. The transient expression of a PaCCoAOMT-GFP fusion gene in tobacco demonstrated that in planta, PaCCoAOMTs are likely directed to the cytoplasm.


Assuntos
Metiltransferases/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Polypodiaceae/enzimologia , Arabidopsis , Flavonóis/metabolismo , Genes de Plantas/genética , Cinética , Lignina/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Metiltransferases/fisiologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Polypodiaceae/genética , Polypodiaceae/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
8.
J Cell Physiol ; 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30387149

RESUMO

During pregnancy, a tremendous increase in fetoplacental angiogenesis is associated with elevated blood flow. Aberrant fetoplacental vascular function may lead to pregnancy complications including pre-eclampsia. Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) are crucial regulators of fetoplacental endothelial function. G protein α subunit 14 (GNA14), a member of Gαq/11 subfamily is involved in mediating hypertensive diseases and tumor vascularization. However, little is known about roles of GNA14 in mediating the FGF2- and VEGFA-induced fetoplacental endothelial function. Using human umbilical vein endothelial cells (HUVECs) cultured under physiological chronic low oxygen (3% O2 ) as a cell model, we show that transfecting cells with adenovirus carrying GNA14 complementary DNA (cDNA; Ad-GNA14) increases (p < 0.05) protein expression of GNA14. GNA14 overexpression blocks (p < 0.05) FGF2-stimulated endothelial migration, whereas it enhances (p < 0.05) endothelial monolayer integrity (maximum increase of ~35% over the control at 24 hr) in response to FGF2. In contrast, GNA14 overexpression does not significantly alter VEGFA-stimulated cell migration, VEGFA-weakened cell monolayer integrity, and intracellular Ca++ mobilization in response to adenosine triphosphate (ATP), FGF2, and VEGFA. GNA14 overexpression does not alter either FGF2- or VEGFA-induced phosphorylation of ERK1/2. However, GNA14 overexpression time-dependently elevates (p < 0.05) phosphorylation of phospholipase C-ß3 (PLCß3) at S1105 in response to FGF2, but not VEGFA. These data suggest that GNA14 distinctively mediates fetoplacental endothelial cell migration and permeability in response to FGF2 and VEGFA, possibly in part by altering activation of PLCß3 under physiological chronic low oxygen.

9.
Data Brief ; 20: 805-811, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30211279

RESUMO

This data article contains descriptive and experimental data on the construction, expression, and simple characterization of AG11-843 and AG11-1581. AG1 is an important member of the DUF1220 protein family. It׳s hard to get the recombinant protein because of its DNA sequence. The DNA sequence were optimized by proper design, cloned by overlap PCR and constructed into expression vector. AG11-843 and AG11-1581.were over expressed in Escherichia coli, purified and analyzed by dynamic light scattering and gel filtration analysis. An effective technique is provided to construct and express proteins with complicated sequences.

10.
Mol Genet Genomics ; 293(6): 1523-1534, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30101382

RESUMO

Iron (Fe) deficiency is a frequent nutritional problem limiting apple production in calcareous soils. The utilization of rootstock that is resistant to Fe deficiency is an effective way to solve this problem. Malus halliana is an Fe deficiency-tolerant rootstock; however, few molecular studies have been conducted on M. halliana. In the present work, a transcriptome analysis was combined with qRT-PCR and sugar measurements to investigate Fe deficiency responses in M. halliana roots at 0 h (T1), 12 h (T2) and 72 h (T3) after Fe deficiency stress. Total of 2473, 661, and 776 differentially expressed genes (DEGs) were identified in the pairs of T2 vs. T1, T3 vs. T1, and T3 vs. T2, respectively. Several DEGs were enriched in the photosynthesis, glycolysis and gluconeogenesis, tyrosine metabolism and fatty acid degradation pathways. The glycolysis and photosynthesis pathways were upregulated under Fe deficiency. In this experiment, sucrose accumulated in Fe-deficient roots and leaves. However, the glucose content significantly decreased in the roots, while the fructose content significantly decreased in the leaves. Additionally, 15 genes related to glycolysis and sugar synthesis and sugar transport were selected to validate the accuracy of the transcriptome data by qRT-PCR. Overall, these results indicated that sugar synthesis and metabolism in the roots were affected by Fe deficiency. Sugar regulation is a way by which M. halliana responds to Fe deficiency stress.

11.
Molecules ; 23(7)2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973530

RESUMO

Alkenal double bond reductases (DBRs), capable of catalyzing the NADPH-dependent reduction of the α,β-unsaturated double bond, play key roles in the detoxication of alkenal carbonyls. Here, the isolation and characterization of two DBRs encoded by the liverwort species Marchantia paleacea are described. The two DBRs share a relatively low similarity, and phylogenetic analysis indicated that MpMDBRL is more closely related to microbial DBRs than to other plant DBRs, while MpDBR shares common ancestry with typical plant DBRs. Both DBR proteins exhibited hydrogenation ability towards hydroxycinnamyl aldehydes; however, their temperature optimums were strikingly different. MpMDBRL demonstrated slightly weaker catalytic efficiency compared to MpDBR, and the structural models of their active binding sites to the substrate may provide a parsimonious explanation. Furthermore, both DBRs significantly responded to phytohormone treatment. In conclusion, M. paleacea produces two distinct types of functional DBRs, both of which participate in the protection against environmental stress in liverwort. The presence of a microbial type of DBR in a plant is herein reported for the first time.


Assuntos
Marchantia/enzimologia , Oxirredutases/genética , Oxirredutases/metabolismo , Domínio Catalítico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hidrogenação , Marchantia/química , Marchantia/genética , Modelos Moleculares , Oxirredutases/química , Filogenia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 30(3): 255-259, 2018 May 24.
Artigo em Chinês | MEDLINE | ID: mdl-30019549

RESUMO

OBJECTIVE: To evaluate the effects of the strategy of transmission interruption of schistosomiasis in Runzhou District, Zhenjiang City, Jiangsu Province. METHODS: The comprehensive prevention and control strategy was carried out in RunzhouDistrict, Zhenjiang City, Jiangsu Province. The strategy was relied mainly on the Oncomelania hupensis snail control, extended chemotherapy of schistosomiasis in residents and the health education. The infection rate of schistosomiasis in residents, area with snails, area with snails controlled, and the rates of awareness and correct behavior of schistosomiasis were as evaluation indexes. RESULTS: The area with snails controlled was 7 091.50 hm2 in Runzhou District, Zhenjiang City from 2001 to 2016. The area with snails reduced year by year from 2001 to 2016. There was a negative correlation between the coverage intensity of snail control and the area with snails (r = -0.874, P = 0). There were 1 703 serum positive and 199 fecal positive people of schistosomiasis in the permanent residents from 2001 to 2016. These serum and fecal positive people of schistosomiasis were all treated with praziquantel. The serum positive rate of schistosomiasis in the permanent residents dropped to below 1.0% after 2005. The fecal positive patients were not found in 2004 and later. Totally 189 639 people received the questionnaire survey for the knowledge of schistosomiasis control from 2001 to 2016. The rates of awareness and correct behavior of schistosomiasis were raised in the residents year by year. The goal of the transmission interruption of schistosomiasis came to true in Runzhou District, Zhenjiang City in 2016. CONCLUSIONS: The comprehensive prevention and control strategy including mainly the snail control, extended chemotherapy of schistosomiasis and health education could achieve the goal of transmission interruption of schistosomiasis in the areas of marshland along the Yangtze River.

13.
BMC Genomics ; 19(1): 461, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29902966

RESUMO

BACKGROUND: Iron (Fe) is an essential micronutrient for plants. Utilization of Fe deficiency-tolerant rootstock is an effective strategy to prevent Fe deficiency problems in fruit trees production. Malus halliana is an apple rootstock that is resistant to Fe deficiency; however, few molecular studies have been conducted on M. halliana. RESULTS: To evaluate short-term molecular response of M. halliana leaves under Fe deficiency condition, RNA sequencing (RNA-Seq) analyses were conducted at 0 (T1), 0.5 (T2) and 3 d (T3) after Fe-deficiency stress, and the timepoints were determined with a preliminary physiological experiment. In all, 6907, 5328, and 3593 differentially expressed genes (DEGs) were identified in pairs of T2 vs. T1, T3 vs. T1, and T3 vs. T2. Several of the enriched DEGs were related to heme binding, Fe ion binding, thylakoid membranes, photosystem II, photosynthesis-antenna protein, porphyrin and chlorophyll metabolism and carotenoid biosynthesis under Fe deficiency, which suggests that Fe deficiency mainly affects the photosynthesis of M. halliana. Additionally, we found that Fe deficiency induced significant down-regulation in genes involved in photosynthesis at T2 when seedlings were treated with Fe-deficient solution for 0.5 d, indicating that there was a rapid response of M. halliana to Fe deficiency. A strong up-regulation of photosynthesis genes was detected at T3, which suggested that M. halliana was able to recover photosynthesis after prolonged Fe starvation. A similar expression pattern was found in pigment regulation, including genes for coding chlorophyllide a oxygenase (CAO), ß-carotene hydroxylase (ß-OHase), zeaxanthin epoxidase (ZEP) and 9-cis-epoxycarotenoid dioxygenase (NCED). Our results suggest that pigment regulation plays an important role in the Fe deficiency response. In addition, we verified sixteen genes related to photosynthesis-antenna protein, porphyrin and chlorophyll metabolism and carotenoid biosynthesis pathways using quantitative real-time PCR (qRT-PCR) to ensure the accuracy of transcriptome data. Photosynthetic parameters, Chl fluorescence parameters and the activity of Chlase were also determined. CONCLUSIONS: This study broadly characterizes a molecular mechanism in which pigment and photosynthesis-related regulations play indispensable roles in the response of M. halliana to short-term Fe deficiency and provides a basis for future analyses of the key genes involved in the tolerance of Fe deficiency.

14.
Protein Expr Purif ; 152: 71-76, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29870801

RESUMO

AG1, a member of the DUF1220 protein family, exhibits the most extreme human lineage-specific copy number expansion of any protein-coding sequence in the genome. These variations in copy number have been linked to both brain evolution among primates and brain size in humans. Unfortunately, our current understanding of the structure and function of these proteins is limited because current cloning and expression techniques fail to consistently produce recombinant protein for in vitro studies. The present work describes a method for amino acid and DNA sequence optimization and synthesis, recombinant protein expression and analysis of two AG1 fragments, AG11-843 and AG11-1581. It was first necessary to modify the nucleotide sequence, while holding the GC content at 52.9%. The genes were then sectionally synthesized by overlap PCR. The resulting segments were cloned into the pET-15 b-sumo expression vector and subsequently transformed into BL21 (DE3) cells. After inducing their expression, the AG11-843 and AG11-1581 proteins were isolated and purified. Furthermore, using dynamic light scattering and gel filtration analysis, AG11-843 and AG11-1581 were shown to be present in tetrameric and dimeric forms in solution. To our knowledge, this is the first study to synthesize and express fragments of the DUF1220 protein family for in vitro analysis. Taken together, the proven utility and versatility of this method indicate that it can be used as an effective technique to construct and express other proteins with complicated sequences, thus providing the means to study their function and structure in vitro.

15.
J Physiol ; 596(12): 2333-2344, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29659033

RESUMO

KEY POINTS: Fetoplacental vascular growth is critical to fetal growth. Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) are two major regulators of fetoplacental vascular growth. G protein α subunit 11 (GNA11) transmits signals from many external stimuli to the cellular interior and may mediate endothelial function. It is not known whether GNA11 mediates FGF2- and VEGFA-induced endothelial cell responses under physiological chronic low O2 . In the present study, we show that knockdown of GNA11 significantly decreases FGF2- and VEGFA-induced fetoplacental endothelial cell migration but not proliferation and permeability. Such decreases in endothelial migration are associated with increased phosphorylation of phospholipase C-ß3. The results of the present study suggest differential roles of GNA11 with respect to mediating FGF2- and VEGFA-induced fetoplacental endothelial function. ABSTRACT: During pregnancy, fetoplacental angiogenesis is dramatically increased in association with rapidly elevated blood flow. Any disruption of fetoplacental angiogenesis may lead to pregnancy complications such as intrauterine growth restriction. Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) are crucial regulators of fetoplacental angiogenesis. G protein α subunits q (GNAq) and 11 (GNA11) are two members of the Gαq/11 subfamily involved in mediating vascular growth and basal blood pressure. However, little is known about the roles of GNA11 alone with respect to mediating the FGF2- and VEGFA-induced fetoplacental endothelial function. Using a cell model of human umbilical cord vein endothelial cells cultured under physiological chronic low O2 (3% O2 ), we showed that GNA11 small interfering RNA (siRNA) dramatically inhibited (P < 0.05) FGF2- and VEGFA-stimulated fetoplacental endothelial migration (by ∼36% and ∼50%, respectively) but not proliferation and permeability. GNA11 siRNA also elevated (P < 0.05) FGF2- and VEGFA-induced phosphorylation of phospholipase C-ß3 (PLCß3) at S537 in a time-dependent fashion but not mitogen-activated protein kinase 3/1 (ERK1/2) and v-akt murine thymoma viral oncogene homologue 1 (AKT1). These data suggest that GNA11 mediates FGF2- and VEGFA-stimulated fetoplacental endothelial cell migration partially via altering the activation of PLCß3.

16.
Plant Cell Physiol ; 59(6): 1187-1199, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29528434

RESUMO

Liverworts, a section of the bryophyte plants which pioneered the colonization of terrestrial habitats, produce cyclic bisbibenzyls as secondary metabolites. These compounds are generated via the phenylpropanoid pathway, similar to flavonoid biosynthesis, for which basic helix-loop-helix (bHLH) transcription factors have been identified as one of the important regulators in higher plants. Here, a bHLH gene homolog (PabHLH) was isolated from the liverwort species Plagiochasma appendiculatum and its contribution to bisbibenzyl biosynthesis was explored. Variation in the abundance of PabHLH transcript mirrored that of tissue bisbibenzyl content in three different liverwort tissues. A phylogenetic analysis based on the bHLH domain sequence suggested that the gene encodes a member of bHLH subgroup IIIf, which clusters proteins involved in flavonoid synthesis. The gene's transient expression in onion epidermal cells implied that its product localized to the nucleus, and a transactivation assays in yeast showed that it was able to activate transcription. In both callus and thallus, the overexpression of PabHLH boosted bisbibenzyl accumulation, while also up-regulating PaPAL, Pa4CL1, PaSTCS1 and two genes encoding P450 cytochromes, and its RNA interference (RNAi)-induced suppression down-regulated the same set of genes and reduced the accumulation of bisbibenzyls. The abundance of PaCHS and PaFNSI transcript was related to flavonoid accumulation in transgenic thallus. PabHLH represents a candidate for the metabolic engineering of bisbibenzyl content.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bibenzilas/metabolismo , Regulação da Expressão Gênica de Plantas , Hepatófitas/genética , Sequência de Aminoácidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Bibenzilas/química , Vias Biossintéticas , Genes Reporter , Hepatófitas/citologia , Hepatófitas/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes de Fusão , Alinhamento de Sequência , Ativação Transcricional
17.
Molecules ; 23(3)2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-29518887

RESUMO

Selaginella is an extant lycopodiophyte genus, which is representative of an ancient lineage of tracheophytes. The important evolutionary status makes it a valuable resource for the study of metabolic evolution in vascular plants. 4-coumarate: CoA ligase (4CL) is the pivotal enzyme that controls the flow of carbon through the phenylpropanoid metabolic pathway into the specific lignin, flavonoid, and wall-bound phenolics biosynthesis pathways. Although 4CLs have been extensively characterized in other vascular plants, little is known of their functions in Selaginella. Here, we isolated two 4CL genes (Sm4CL1 and Sm4CL2) from Selaginella moellendorffii. Based on the enzymatic activities of the recombinant proteins, both of these genes encoded bona fide 4CLs. The 4CL isoforms in S. moellendorffii have different activities: Sm4CL2 was more active than Sm4CL1. The enzymatic properties and gene expression patterns indicated that the 4CL genes have been conserved in the evolution of vascular plants.


Assuntos
Clonagem Molecular , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Expressão Gênica , Selaginellaceae/genética , Selaginellaceae/metabolismo , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Coenzima A Ligases/química , Ativação Enzimática , Regulação da Expressão Gênica de Plantas , Especificidade de Órgãos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Propanóis/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Selaginellaceae/classificação , Análise de Sequência de DNA
18.
Plant Physiol Biochem ; 125: 95-105, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29428820

RESUMO

Chalcone synthases (CHSs) of the type III polyketide synthases (PKSs), catalyze the formation of a tetraketide intermediate from a CoA-tethered starter and malonyl-CoA but use different cyclization mechanisms to produce distinct chemical scaffolds. Herein, we characterized CHS and CHS-like enzymes (designated MpCHS and MpCHSL1, 2 and 3) from Marchantia paleacea and determined the crystal structure of MpCHSL1. MpCHS catalyzed a Claisen condensation to form chalcone, while MpCHSLs catalyzed the formation of lactonized α-pyrones in vitro. Based on the structural, mutational and in vitro biochemical analyses, we established that MpCHSL1 is structurally and functionally closer to prototype CHS than stilbene synthase, and characterized the structural basis for the functional diversity of the type III PKSs. A chalcone-forming mutant of MpCHSL1 was build directed by the structural information. These findings pave the way for future studies to elucidate the functional diversity of type III PKSs in liverwort.


Assuntos
Marchantia/enzimologia , Proteínas de Plantas/química , Policetídeo Sintases/química , Domínios Proteicos , Relação Estrutura-Atividade
19.
Mol Cell Endocrinol ; 470: 228-239, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29122660

RESUMO

Galectin-1 is highly expressed in blastocysts and trophoblast giant cells during implantation, and dysregulated galectin-1 is associated with many pregnancy-related abnormalities. Elevated galectin-1 contributes to cancer cells invasion. Here, we found that galectin-1 is expressed in mouse oocytes, preimplantation embryos (all stages), and trophoblast stem (TS) cells. Peak levels of galectin-1 mRNA and protein were detected on day 4 and day 5 after the induction of TS cells differentiation. Overexpression of galectin-1 increased TS cells migration and invasion, whereas knockdown of galectin-1 attenuated these effects. Additionally, knockdown of galectin-1 in TS cells decreased the expression of matrix metalloproteinase (MMP) 2/9, ZEB-1, Snail, N-cadherin, TGF-ß, Nodal, and phospho-Smad2/3, whereas the expression of E-cadherin was increased. In contrast, overexpression of galectin-1 in TS cells increased the expression of MMP2/9, ZEB-1, and N-cadherin, whereas the expression of E-cadherin was decreased. These findings suggest a potential role of galectin-1 in the differentiation of mouse TS cells.

20.
New Phytol ; 217(2): 909-924, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29083033

RESUMO

Flavonoids ubiquitously distribute to the terrestrial plants and chalcone isomerase (CHI)-catalyzed intramolecular and stereospecific cyclization of chalcones is a committed step in the production of flavonoids. However, so far the bona fide CHIs are found only in vascular plants, and their origin and evolution remains elusive. We conducted transcriptomic and/or genomic sequence search, subsequent phylogenetic analysis, and detailed biochemical and genetic characterization to explore the potential existence of CHI proteins in the basal bryophyte liverwort species and the lycophyte Selaginella moellendorffii. We found that both liverwort and Selaginella species possess canonical CHI-fold proteins that cluster with their corresponding higher plant counterparts. Among them, some members exhibited bona fide CHI activity, which catalyze stereospecific cyclization of both 6'-hydroxychalcone and 6'-deoxychalcone, yielding corresponding 5-hydroxy and 5-deoxyflavanones, resembling the typical type II CHIs currently known to be 'specific' for legume plants. Expressing those primitive bona fide CHIs in the Arabidopsis chi mutant restores the seed coat transparent testa phenotype and the accumulation of flavonoids. These findings, in contrast to our current understanding of the evolution of enzymatic CHIs, suggest that emergence of the bona fide type II CHIs is an ancient evolution event that occurred before the divergence of liverwort lineages.

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