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1.
Sensors (Basel) ; 19(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540537

RESUMO

Unmanned Aerial Vehicles (UAVs) are widely used as mobile information collectors for sensors to prolong the network time in Wireless Sensor Networks (WSNs) due to their flexible deployment, high mobility, and low cost. This paper focuses on the scenario where rotary-wing UAVs complete information collection mission cooperatively. For the first time, we study the problem of minimizing the mission completion time for a multi-UAV system in a monitoring scenario when considering the information collection quality. The mission completion time includes flying time and hovering time. By optimizing the trajectories of all UAVs, we minimize the mission completion time while ensuring that the information of each sensor is collected. This problem can be formulated as a mixed-integer non-convex one which has been proved to be NP-hard. To solve the formulated problem, we first propose a hovering point selection algorithm to select appropriate hovering points where the UAVs can sequentially collect the information from multiple sensors. We model this problem as a BS coverage problem with the information collection quality in consideration. Then, we use a min-max cycle cover algorithm to assign these hovering points and get the trajectory of each UAV. Finally, with the obtained UAVs trajectories, we further consider the UAVs can also collect information when flying and optimize the time allocations. The performance of our algorithm is verified by simulations, which show that the mission completion time is minimum compared with state-of-the-art algorithms.

2.
Plant Biotechnol J ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31559685

RESUMO

High temperature adversely affects plant growth and severely causes crop yield loss worldwide, especially for chimonophilous wheat (Triticum aestivum L.; Akter and Islam, 2017). Heat shock transcription factors (HSFs) and plant hormones play regulatory roles in plant responses to heat stress (Baniwal et al., 2004). In this study, we found that TaOPR3 contributes to heat tolerance in wheat probably via regulating JA level.

3.
Dalton Trans ; 48(40): 15114-15120, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31559981

RESUMO

Complex [Ir(dfppy)2(phca)]PF6 (1) has been synthesized, which contains an aldehyde group in the N^N ligand phca = 1,10-phenanthroline-4-carbaldehyde, with the aim of exploring solvent-driven luminescence modulation/switching in this complex. Complex 1 shows green emission at 514 nm in CH3OH, while orange phosphorescence with the emissions at 516 and 624 nm in CH2Cl2. The solid-state structure of 1 is dependent on the crystallization solvent used, forming a red solid 1R in CH2Cl2, while a yellow solid 1Y in CHCl3. The neighboring [Ir(dfppy)2(phca)]+ cations in solid 1R are held together by ππ stacking interactions, while by van der Waals interactions in solid 1Y. The distinct packing structures of 1R and 1Y lead to their significantly different solid-state luminescence, weak orange phosphorescence for 1R (emission at 620 nm, Φ = 3.3%) and strong yellow phosphorescence for 1Y (emissions at 532 and 558 nm, Φ = 46.6%). Both 1R and 1Y show CH2Cl2/CHCl3-driven phosphorescence switching between orange and yellow, due to their structural interconversion through recrystallization. Moreover, the emission color of 1Y can be reversibly switched between yellow and orange through alternate pressing and recrystallization in CHCl3. This work discusses the relationship among the solvent, the structure and the luminescence modulation/switching of complex 1.

4.
Mol Ther Nucleic Acids ; 18: 110-122, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31541797

RESUMO

Myocardial infarction (MI) is a life-threatening cardiac event that results in extreme damage to the heart muscle. The Wnt signaling pathway has been implicated in the development of heart diseases. Hence, the current study aimed to investigate the role of microRNA (miRNA) in association with the Wnt signaling pathway to identify potential candidates for MI therapy. Differentially expressed miRNAs associated with MI occurrence were screened, and miR-494 was selected for subsequent experiments. Sprague-Dawley rats were included to establish a MI model via intraperitoneal injection of 0.1 mg/kg atropine sulfate and 40 mg/kg pentobarbital sodium. Then, the interaction between miR-494 and LRG1 was identified. The effect of miR-494 on expression of the Wnt signaling pathway-related genes, proliferation, migration, and invasion ability of fibroblasts and vascular endothelial cells (VECs) was subsequently evaluated through a series of gain- and loss-of-function experiments. The results revealed that miR-494 was poorly expressed and LRG1 was highly expressed in MI rats. miR-494 targets and downregulates LRG1, which resulted in the inactivation of the Wnt signaling pathway and promoted proliferation, migration, and invasion ability of fibroblasts and VECs. In conclusion, this study provided evidence suggesting that overexpressed miR-494 could potentially promote the proliferation, migration, and invasion of fibroblasts and VECs in MI through the inactivation of the Wnt signaling pathway by binding to LRG1.

5.
Food Chem ; 299: 125037, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279128

RESUMO

Immobilization of enzymes is an essential strategy with outstanding prospects in biocatalytic processes. Nontoxic, inexpensive immobilized enzyme approach is especially important for food enzymes. We here demonstrate that a carbohydrate-binding module family 56 domain (CBM56-Tag) mediates the immobilization of fusion enzymes with the curdlan (ß-1,3-glucan) particle support, thereby enabling the one-step immobilization-purification of target enzymes. CBM56-Tag exhibits an immunoglobulin-like ß-sandwich fold, which can be adsorbed by curdlan via hydrogen bond-mediated binding. The maximum adsorption capacity of a fusion chitosanase (CBM56-GsCsn46A) on curdlan is 50.72 mg/g. The immobilized enzyme could be directly used in the packed-bed reactor. This immobilization strategy utilizes a natural polysaccharide without any treatment, avoiding the negative environmental effects. Moreover, the one step immobilization-purification simplifies the purification step, which reduces the use of chemicals. Our study provides a nontoxic and inexpensive immobilization strategy for the biocatalytic reaction in food industry.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/isolamento & purificação , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Biocatálise , Enzimas Imobilizadas/metabolismo , Glicosídeo Hidrolases/metabolismo , Ligações de Hidrogênio , beta-Glucanas/química
6.
Oncogene ; 38(36): 6354-6369, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31320708

RESUMO

Metastasis is the leading cause of lung cancer-related death. Elucidating the metastasis process can provide new avenues to inhibit this malignant behavior of cancer cells. Here we found that human lung cancers with high Keratin 14 (K14) expression were associated with nodal metastasis and poor survival. Using the KrasG12D/Trp53L/L lung cancer mouse model, we confirmed that K14-high cancer cells harbored increased metastatic potential. Mechanistic investigation revealed that Gastrokine 1 (Gkn1) expression positively correlated with K14 level, cancer metastasis, and poor patient survival. Importantly, ectopic expression of Gkn1 enhanced the metastatic capability of K14-low cells in vitro and in vivo, whereas knockdown of Gkn1 did the opposite, indicating the importance of Gkn1 in mediating the metastasis of K14-high cells. Further study demonstrated that Gkn1 expression conferred K14-high cells resistance to anoikis, which is critical for cancer metastasis. Collectively, our findings demonstrate that K14-high cells contribute to lung cancer metastasis potentially through inhibition of anoikis via upregulation of Gkn1.

7.
J Food Biochem ; 43(5): e12831, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31353518

RESUMO

This study investigated the intervention effects of chitooligosaccharides (COS) on retinol metabolism and included comparisons of the retinol level, retinol binding protein 4 (RBP4) content, key genes, and protein expression between mice on a COS-enriched diet and a normal diet. The results showed that COS markedly decreased the retinol and RBP4 concentrations in the serum and liver. Furthermore, COS suppressed the mRNA and protein expression of RBP4, cellular retinol binding protein 1 (CRBP1), lecithin: retinol acyltransferase (LRAT) and cytochrome P45026A1 (CYP26A1). In addition, COS inhibited the mRNA expression of stimulated by retinoic acid 6 (STRA6). However, the protein expression of STRA6 was not significantly decreased. Thus, COS reduced the retinol concentration in the serum and disrupted the metabolism of retinol. The intervention mechanism of COS on retinol metabolism may be attributed to the modulation of RBP4, CRBP1, LRAT, STRA6, and CYP26A1 expression at the mRNA and protein levels. PRACTICAL APPLICATIONS: Chitooligosaccharides (COS), known to be the degradation products of chitosan, have been found to induce pinkeye in industrial workers who participate in the manufacturing of COS. Meanwhile, 5% population with COS dietary supplement also have similar phenomenon. The aim of this study is to explore the possible mechanism underlay of this potential risk. The results of this study showed that high exposure to COS during manufacture influences retinol metabolism and leads to a decrease in retinol content, ultimately causing pinkeye. These findings provide new evidence for understanding COS-induced retinol metabolism alteration and drawing attention toward the prevention of potential risk in high-exposure populations.

8.
Microb Pathog ; 134: 103598, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201901

RESUMO

BACKGROUND: Polymorphisms near the interferon lambda 3 (IFNL3, also known as IL28B) have been proposed to be associated with interferon (IFN)-induced hepatitis C virus (HCV) clearance, but the impact of IFNL3 variations on the result of IFN-based therapy in chronic hepatitis B (CHB) infection is still poor understood. METHODS: The purpose of this study was to evaluate the relationship between the IFNL3 polymorphisms and the effectiveness of IFN therapy in patients infected with CHB by means of meta-analysis. PubMed and Embase were utilized to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were analysed together to assess the strength of the association. Subgroup analysis was mainly performed according to HBeAg. RESULTS: Twelve studies of 1645 CHB patients met the inclusion criteria and were selected in our meta-analysis. One polymorphism, rs12979860, near to the IFNL3 gene had significant association with the response of CHB patients to IFN-based therapy (OR = 2.35, 95% CI: 1.61-3.42 in allelic model). Another polymorphism, rs8099917, had a similar result (OR = 1.57, 95% CI: 1.03-2.40 in dominant model; and OR = 1.88, 95% CI: 1.21-2.90 in allelic model). When stratified by HBeAg, the antiviral outcome was markedly influenced by both two SNPs in HBeAg positive group (for rs12979860, OR = 1.90, 95% CI: 1.31-2.76 and OR = 2.07, 95% CI: 1.26-3.41 in dominant and allelic models respectively; for rs8099917, OR = 1.67, 95% CI: 1.04-2.67 in dominant model and OR = 1.77, 95% CI: 1.10-2.85 in allelic model). CONCLUSION: We concluded that two polymorphisms (rs12979860 and rs8099917) of IFNL3 may play a crucial role in the IFN-based treatment of CHB, especially in HBeAg positive group.

9.
Curr Issues Mol Biol ; 32: 645-700, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31166182

RESUMO

Streptococcus pneumoniae (Spn) and Streptococcus pyogenes (Spy) cause many invasive and noninvasive diseases responsible for high morbidity and mortality worldwide. Safe, efficacious and affordable vaccines could have a significant, positive impact on the global infectious disease burden. Since the implementation of pneumococcal vaccine in the 1980s, the incidence of Spn infection has decreased significantly. Still so, these currently used multivalent polysaccharides and conjugated pneumococcal vaccines have some limitations. For Spy, there are even no vaccines available yet. There is an urgent need of new vaccines against Spn and Spy. Encouragingly, with the hard work of many investigators worldwide, a number of new vaccines candidates are developed with promising results. Of them, many have already entered the clinical trial stage. This review will describe the current status of Spn and Spy vaccine development, with particular focus on protein-based strategy.

10.
J Mol Cell Cardiol ; 133: 12-25, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31145943

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) play a central role in regulating heart diseases. In the present study, we examined the effects of lncRNA taurine up-regulated gene 1 (TUG1) in ischemia/reperfusion (I/R)- or hydrogen peroxide-challenged cardiomyocytes, with specific focus on autophagy-induced cell apoptosis. METHODS: The expressions of miR-142-3p and TUG1 in H2O2-challenged cardiomyocytes and I/R-injured heart tissue were measured by RT-qPCR. Cell death was measured by trypan blue staining assay. Cell apoptosis was determined by Annexin V/PI staining and TUNEL assay. Autophagy was examined by quantifying cells or tissues containing LC3+ autophagic vacuoles by immunofluorescence, or by measuring the expressions of autophagy-related biomarkers by Western blot. The direct interaction between miR-142-3p and TUG1, high mobility group box 1 protein (HMGB1), or Ras-related C3 botulinum toxin substrate 1 (Rac1) was examined using luciferase reporter assay. The significance of miR-142-3p and TUG1 on cell apoptosis or autophagy was examined using both gain-of-function and loss-of-function approaches. The importance of HMGB1 or Rac1 was assessed using siRNA-mediated gene silencing. RESULTS: miR-142-3p was down-regulated, while TUG1 up-regulated in H2O2-challenged cardiomyocytes in vitro and I/R-injured heart tissues in vivo. Functionally, inhibition of TUG1 and overexpression of miR-142-3p inhibited cell apoptosis and autophagy in cardiomyocytes. The function of TUG1 were achieved by sponging miR-142-3p and releasing the suppression of the putative targets of miR-142-3p, HMGB1 and Rac1. Both HMGB1 and Rac1 essentially mediated cell apoptosis and autophagy induced by TUG1. CONCLUSIONS: TUG1, by targeting miR-142-3p and up-regulating HMGB1 and Rac1, plays a central role in stimulating autophagic cell apoptosis in ischemia/hypoxia-challenged cardiomyocytes. Down-regulating TUG1 or up-regulating miR-142-3p may ameliorate myocardial injury and protect against acute myocardial infarction.

11.
Anal Chem ; 91(11): 7215-7225, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31082218

RESUMO

Isotope analysis of trace uranium is important in nuclear safeguards and nuclear forensics, which requires the analytical methodologies with high sensitivity, accuracy, and precision. As one of the most powerful techniques in isotopic measurement, thermal ionization mass spectrometry (TIMS) usually suffers from its relatively low sensitivity in ultratrace measurements. To overcome this limitation, we have developed a new filament carburization technique for TIMS, with graphene oxide (GO) as the ionization enhancer. A high and steady ionization efficiency of ∼0.2% for uranium was achieved in single-filament mode, which was 10× the classical double-filament method. With total evaporation (TE) measurements, this method was validated with certified reference materials (CRMs) at the picogram level, and the relative uncertainties for n(235U)/ n(238U) were as low as the ∼1% level. The enhancement mechanism of GO's promoting effect on uranium ionization was attributed to the uniform microstructure facilitating energy transfer and formation of carbides. This approach provides an alternative simple and rapid method for trace uranium isotope analysis with high sensitivity and excellent repeatability. Filament carburization and uranium loading could be accomplished within 10 min. This technique has great advantage in analysis of trace uranium isotope ratios and can be applied in the researches of environmental analysis and nuclear forensics.

12.
J Acoust Soc Am ; 145(4): EL277, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31046369

RESUMO

The sparse direct adaptive equalizer (DAE) has recently attracted much attention in underwater acoustic (UWA) communications for its improved performance compared with conventional non-sparse DAEs. The recursive least squares (RLS) type sparse DAEs were barely studied, mainly due to their high complexity despite fast convergence. This letter presents several low-complexity sparse RLS algorithms for multiple-input multiple-output UWA channel equalization. The resulting fast sparse RLS DAEs are tested to be effective and outperform their non-sparse counterpart by experimental results.

13.
World J Microbiol Biotechnol ; 35(6): 87, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31134386

RESUMO

Biofilms enable Cronobacter spp. to contaminate food, infect infants and resist different environmental stresses, especially desiccation, which is the main reason why Cronobacter can survive in powdered infant formula (PIF) for a long time. Considering the high lethality of Cronobacter infection in infants, it is important to find efficient and safe inhibitors of Cronobacter biofilms. In this study, we found that chitooligosaccharides (COS) with a molecular weight of 2000 Da efficiently inhibited Cronobacter biofilms, especially in skim milk broth. The minimum biofilm inhibitory concentration (MBIC77) of COS was as low as 20 µg/mL, which is lower than that reported in most previous studies. Besides, the elimination rate of COS for Cronobacter mature biofilms was 50% when the concentration was 10 mg/mL. COS could significantly inhibit soluble polysaccharide secretion and biofilm cell growth, as well as change the cell membrane permeability of Cronobacter. These might be the possible reasons for COS's efficient inhibition of Cronobacter biofilms. However, during the inhibition, five important genes-related to biofilm formation-flhD, flgJ, luxR, ompA, and wcaJ-were all up-regulated after COS treatment, except the gene bcsA. In summary, our findings showed that COS could be used as an efficient and safe inhibitor against Cronobacter biofilms for better control of Cronobacter contamination and infection.


Assuntos
Biofilmes/efeitos dos fármacos , Quitina/análogos & derivados , Cronobacter/efeitos dos fármacos , Animais , Biofilmes/crescimento & desenvolvimento , Membrana Celular/efeitos dos fármacos , Quitina/química , Quitina/farmacologia , Cronobacter/genética , Infecções por Enterobacteriaceae , Contaminação de Alimentos , Microbiologia de Alimentos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos/genética , Testes de Sensibilidade Microbiana , Leite , Peso Molecular
14.
J Agric Food Chem ; 67(24): 6847-6855, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31132258

RESUMO

Chitooligosaccharide has been reported to possess diverse bioactivities. The development of novel strategies for obtaining optimum degree of polymerization (DP) chitooligosaccharides has become increasingly important. In this study, two glycoside hydrolase family 46 chitosanases were studied for immobilization on curdlan (insoluble ß-1,3-glucan) using a novel carbohydrate binding module (CBM) family 56 domain from a ß-1,3-glucanase. The CBM56 domain provided a spontaneous and specific sorption of the fusion proteins onto a curdlan carrier, and two fusion enzymes showed increased enzyme stability in comparison with native enzymes. Furthermore, a continuous packed-bed reactor was constructed with chitosanase immobilized on a curdlan carrier to control the enzymatic hydrolysis of chitosan. Three chitooligosaccharide products with different molecular weights were prepared in optimized reaction conditions. This study provides a novel CBM tag for the stabilization and immobilization of enzymes. The controllable hydrolysis strategy offers potential for the industrial-scale preparation of chitooligosaccharides with different desired DPs.


Assuntos
Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Oligossacarídeos/química , Paenibacillus/enzimologia , Biocatálise , Carboidratos/química , Estabilidade Enzimática , Enzimas Imobilizadas/química , Família Multigênica , Paenibacillus/química , Domínios Proteicos , beta-Glucanas/química
15.
Talanta ; 199: 131-139, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952236

RESUMO

Detection and identification of bitter compounds draw great attention in pharmaceutical and food industry. Several well-known agonists of specific bitter taste receptors have been found to exhibit anti-cancer effects. For example, N-C=S-containing compounds, such as allyl-isothiocyanates, have shown cancer chemo-preventive effects. It is worth noting that human T2R38 receptor is specific for compounds containing N-C=S moiety. Here, a bioinspired cell-based bioelctronic tongue (BioET) is developed for the high-specificity isothiocyanate-induced bitter detection, utilizing human Caco-2 cells as a primary sensing element and interdigitated impedance sensor as a secondary transducer. As an intestinal carcinoma cell line, Caco-2 endogenously expresses human bitter receptor T2R38, and the activation of T2R38 induces the changes of cellular morphology which can be detected by electric cell-substrate impedance sensing (ECIS). After configuration and optimization of parameters including timing of compound administration and cell density, quantitative bitter evaluation models were built for two well-known bitter compounds, phenylthiocarbamide (PTC) and propylthiouracil (PROP). The bitter specific detection of this BioET is inhibited by probenecid and U-73122, and is not elicited by other taste modalities or bitter ligands that do not activate T2R38. Moreover, by combining different computational tools, we designed a ligand-based virtual screening (LBVS) protocol to select ligands that are likely to activate T2R38 receptor. Three computationally predicted agonists of T2R38 were selected using the LBVS protocol, and the BioET presented response to the predicted agonists, validating the capability of the LBVS protocol. This study suggests this unique cell-based BioET paves a general and promising way to specifically detect N-C=S-containing compounds that can be used for pharmaceutical study and drug development.


Assuntos
Nariz Eletrônico , Isotiocianatos/análise , Receptores Acoplados a Proteínas-G/metabolismo , Células CACO-2 , Relação Dose-Resposta a Droga , Humanos , Isotiocianatos/farmacologia , Ligantes , Estrutura Molecular , Feniltioureia/química , Feniltioureia/farmacologia , Propiltiouracila/química , Propiltiouracila/farmacologia , Receptores Acoplados a Proteínas-G/agonistas , Relação Estrutura-Atividade , Células Tumorais Cultivadas
16.
J Cell Physiol ; 234(11): 20533-20545, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31026065

RESUMO

The only Food and Drug Administration-approved treatment for acute ischemic stroke is tissue plasminogen activator, and the discovery of novel therapeutic targets is critical. Here, we found orosomucoid (ORM), an acute-phase protein mainly produced by the liver, might act as a treatment candidate for an ischemic stroke. The results showed that ORM2 is the dominant subtype in mice normal brain tissue. After middle cerebral artery occlusion (MCAO), the level of ORM2 is significantly increased in the ischemic penumbra compared with the contralateral normal brain tissue, whereas ORM1 knockout did not affect the infarct size. Exogenous ORM could significantly decrease infarct size and neurological deficit score. Inspiringly, the best administration time point was at 4.5 and 6 hr after MCAO. ORM could markedly decrease the Evans blue extravasation, and improve blood-brain barrier-associated proteins expression in the ischemic penumbra of MACO mice and oxygen-glucose deprivation (OGD)-treated bEnd3 cells. Meanwhile, ORM could significantly alleviate inflammation by inhibiting the production of interleukin 1ß (IL-1ß), IL-6, and tumor necrosis factor α (TNF-α), reduce oxidative stress by improving the balance of malondialdehyde (MDA) and superoxide dismutase (SOD), inhibit apoptosis by decreasing caspase-3 activity in ischemic penumbra of MCAO mice and OGD-treated bEnd.3 cells. Because of its protective role at multiple levels, ORM might be a promising therapeutic target for ischemic stroke.

17.
ACS Appl Mater Interfaces ; 11(13): 12452-12459, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30860346

RESUMO

Triboelectric nanogenerator could efficaciously harvest the mechanical energy that come from the ambient environment, which has become a research hotspot in the sphere of wearable electronic technology. Here, a self-powered and highly stretchable single-electrode triboelectric nanogenerator with an undulating three-dimensional surface crumpled structure is reported. The triboelectric nanogenerator has a multilayer structure with a crumpled nanofiber membrane as the triboelectric material. Due to the materials and structural innovations, the triboelectric nanogenerator possesses outstanding electric output stability and stretchability. It could subtly transform the unstretched flexible nanofiber membrane into a stretchable material, while overcoming the deficiency that the nanofiber membrane has a tendency to be delaminated from the electrode layer during long-term operation. Utilizing the triboelectric nanogenerator directly attached to human skin could efficaciously harvest the ignored mechanical energy that come from our daily activities.

18.
Nat Genet ; 51(4): 766, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30846878

RESUMO

In the version of this article initially published, the following grant numbers and recipients were missing from the Acknowledgements: XDB19000000 to H.J. and B.Z.; 81430066 and 31621003 to H.J.; 2017YFA0505500 to H.J.; and 15XD1504000 to H.J. The errors have been corrected in the HTML and PDF versions of the article.

19.
Int J Mol Sci ; 20(4)2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781405

RESUMO

Unsaturated fatty acids are the main components of vegetable oils. Fatty acid desaturase 2 (FAD2) catalyzes oleic acid (OA) into linoleic acid (LA) transformations, which are essential to the profile of FAs in seeds. To further understand the roles of FAD2s in the synthesis of oil, the evolution and biocatalysis of FAD2s were comprehensively analyzed. The evolution history of the FAD2 gene family showed that most of the FAD2 genes formed monophyletic clades except in eudicots. The FAD2 genes in some eudicots diverged into constitutive and seed-specific expression clades. Notably, the biocatalysis of seed-specific or -abundant expression FAD2s in soybean, perilla, rice, and spruce revealed that their catalytic activity was strongly correlated with the total oil content of their seeds in nature. Additionally, it was found that I and Y in site 143 of GmaFAD2-1 were strictly conserved in the seed-specific and constitutive expression clades of Fabaceae, respectively. Furthermore, the site-directed mutation demonstrated that I and Y are vital to improving and reducing the activity of GmaFAD2s. Therefore, the results indicate that the activity of FAD2s in seeds might be a reference to the total oil content of seeds, and site 143 might have been specifically evolved to be required for the activity of FAD2s in some expression-diverged eudicots, especially in legumes.


Assuntos
Biocatálise , Evolução Molecular , Ácidos Graxos Dessaturases/genética , Óleos Vegetais/metabolismo , Sementes/metabolismo , Sequência de Aminoácidos , Fabaceae/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Família Multigênica , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo
20.
Nat Genet ; 51(4): 728-738, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30778223

RESUMO

Characterizing the stem cells responsible for lung repair and regeneration is important for the treatment of pulmonary diseases. Recently, a unique cell population located at the bronchioalveolar-duct junctions has been proposed to comprise endogenous stem cells for lung regeneration. However, the role of bronchioalveolar stem cells (BASCs) in vivo remains debated, and the contribution of such cells to lung regeneration is not known. Here we generated a genetic lineage-tracing system that uses dual recombinases (Cre and Dre) to specifically track BASCs in vivo. Fate-mapping and clonal analysis showed that BASCs became activated and responded distinctly to different lung injuries, and differentiated into multiple cell lineages including club cells, ciliated cells, and alveolar type 1 and type 2 cells for lung regeneration. This study provides in vivo genetic evidence that BASCs are bona fide lung epithelial stem cells with deployment of multipotency and self-renewal during lung repair and regeneration.


Assuntos
Bronquíolos/fisiologia , Líquido da Lavagem Broncoalveolar/citologia , Pulmão/fisiologia , Células-Tronco Multipotentes/fisiologia , Regeneração/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Células Cultivadas , Células Epiteliais/fisiologia , Genótipo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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