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1.
Plant Sci ; 312: 111052, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620447

RESUMO

Drought occurrence seriously affects the productivity and quality of apple crop worldwide. Autophagy, a conserved process for the degradation and recycling of unwanted cellular components, is considered to positively regulate the tolerance of various abiotic stresses in plants. In the current study, we isolated two ATG5 homologs genes, namely, MdATG5a and MdATG5b, from apple, demonstrating their responsiveness to drought and oxidative stresses. In addition to having the same cellular localization in the nucleus and cytoplasm, both MdATG5a and MdATG5b could interact with MdATG12. Transgenic apple plants overexpressing MdATG5a exhibited an improved drought tolerance, as indicated by less drought-related damage and higher photosynthetic capacities compared to wild-type (WT) plants under drought stress. The overexpression of MdATG5a improved antioxidant defenses in apple when exposed to drought via elevating both antioxidant enzyme activities and the levels of beneficial antioxidants. Furthermore, under drought stress, the overexpression of MdATG5a promoted the mobilization of starch to accumulate greater levels of soluble sugars, contributing to osmotic adjustments and supporting carbon skeletons for proline synthesis. Such changes in physiological responses may be associated with increased autophagic activities in the transgenic plants upon exposure to drought. Our results demonstrate that MdATG5a-mediated autophagy enhances drought tolerance of apple plants via improving antioxidant defenses and metabolic adjustments.

2.
J Exp Bot ; 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34486649

RESUMO

The high accumulation of phloridzin makes apple (Malus domestica) unique in the plant kingdom, which suggests a vital role of its biosynthesis in the physiological processes of apple. In our previous study, silencing MdUGT88F1 (a key UDP-glucose: phloretin 2'-O-glucosyltransferase gene) revealed the importance of phloridzin biosynthesis in apple development and Valsa canker resistance. Here, results from MdUGT88F1-silencing lines showed that phloridzin biosynthesis was indispensable for normal chloroplast development and photosynthetic carbon fixation by maintaining MdGLK1/2 expression. Interestingly, the increased phloridzin biosynthesis didn't affect plant (or chloroplast) development but reduced nitrogen accumulation, leading to chlorophyll deficiency, light sensitivity, and sugar accumulation in MdUGT88F1-overexpressing apple lines during their growth and development. Further analysis revealed that MdUGT88F1-mediated phloridzin biosynthesis negatively regulated cytosolic glutamine synthetase1-asparagine synthetase-asparaginase (GS1-AS-ASPG) pathway of ammonium assimilation and limited chlorophyll synthesis in the shoots of apple. The interference of phloridzin biosynthesis in the GS1-AS-ASPG pathway was also assumed to be associated with its limitation of the carbon skeletons of ammonium assimilation through metabolic competition with the tricarboxylic acid cycle. Taken together, our findings shed light on the role of MdUGT88F1-mediated phloridzin biosynthesis in the coordination between carbon and nitrogen accumulation in apple trees.

3.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360850

RESUMO

Autophagy is a conserved degradation pathway for recycling damaged organelles and aberrant proteins, and its important roles in plant adaptation to nutrient starvation have been generally reported. Previous studies found that overexpression of autophagy-related (ATG) gene MdATG10 enhanced the autophagic activity in apple roots and promoted their salt tolerance. The MdATG10 expression was induced by nitrogen depletion condition in both leaves and roots of apple plants. This study aimed to investigate the differences in the growth and physiological status between wild type and MdATG10-overexpressing apple plants in response to nitrogen starvation. A hydroponic system containing different nitrogen levels was used. The study found that the reduction in growth and nitrogen concentrations in different tissues caused by nitrogen starvation was relieved by MdATG10 overexpression. Further studies demonstrated the increased root growth and the higher nitrogen absorption and assimilation ability of transgenic plants. These characteristics contributed to the increased uptake of limited nitrogen nutrients by transgenic plants, which also reduced the starvation damage to the chloroplasts. Therefore, the MdATG10-overexpressing apple plants could maintain higher photosynthetic ability and possess better growth under nitrogen starvation stress.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Malus/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Autofagia , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/crescimento & desenvolvimento , Estresse Fisiológico
4.
ACS Chem Neurosci ; 12(17): 3214-3224, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387082

RESUMO

Leucine rich repeat kinase 2 (LRRK2) has been reported in the pathogenesis of Parkinson's disease (PD). Inhibition of LRRK2 kinase activity is a therapeutic approach that may provide new treatments for PD. In this study, novel LRRK2 inhibitors were identified by performing a docking-based virtual screening (VS). Due to the absence of a crystal structure of LRRK2, homology modeling was adopted to model human LRRK2 kinase domain that binds the inhibitor. Next, a docking-based virtual screening protocol was applied to identify LRRK2 small molecule inhibitors targeting the ATP binding pocket. A total of 28 compounds were selected and subjected to LRRK2 kinase inhibition assay. As a result, two small molecules with novel skeleton, compounds LY2019-005 and LY2019-006, were identified as potential LRRK2 kinase inhibitors with the IC50 of these two compounds against the wild-type and G2019S mutant LRRK2 kinase being 424.40 ± 1.31 nM, 378.80 ± 1.20 nM and 1526.00 ± 0.87 nM, 1165.00 ± 1.18 nM, respectively. Molecular dynamics (MD) simulation was carried out to reveal the binding mode of the newly identified compound LY2019-005 to the LRRK2 kinase domain. The binding modes indicate that the important hydrogen bond between hinge region (such as Ala1950) and inhibitor is crucial for the inhibition activity. In summary, our study provides a highly efficient way to discover LRRK2 inhibitors, and we find two highly efficient novel LRRK2 inhibitors, which could be helpful for the development of potential drugs targeting LRRK2 in PD therapy.


Assuntos
Doença de Parkinson , Inibidores de Proteínas Quinases , Humanos , Ligação de Hidrogênio , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Simulação de Dinâmica Molecular , Mutação , Doença de Parkinson/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia
5.
Tree Physiol ; 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34328189

RESUMO

Drought stress is an environmental factor that seriously threatens plant growth, development, and yield. VQ proteins are transcriptional regulators that have been reported to be involved in plant growth, development, and the responses to biotic and abiotic stressors. However, the relationship between VQ proteins and drought stress has not been well documented in plants. In this study, overexpressing the apple VQ motif-containing protein (MdVQ37) gene in apple plants markedly reduced the tolerance to drought. Physiological and biochemical studies further demonstrated lower enzymatic activities and decreased photosynthetic capacity in transgenic lines compared to wild-type (WT) plants under drought stress. Ultrastructural analysis of leaves showed that the leaves and palisade tissues from the transgenic lines were significantly thinner than those from WT plants. Salicylic acid (SA) analysis indicated that overexpression of MdVQ37 increased the accumulation of 2,5-DHBA by up-regulating the expression of the SA catabolic gene, which ultimately resulted to a significant reduction in endogenous SA content and the disruption of the SA-dependent signaling pathway under drought stress. Applying SA partially increased the survival rate of the transgenic lines under drought stress. These results demonstrate that the regulatory function of apple MdVQ37 is implicated in drought stress, through a change in leaf development and SA homeostasis. This study provides novel insight into understanding the multiple functions of VQ proteins.

6.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073055

RESUMO

Plant proline-rich proteins (PRPs) are cell wall proteins that occur in the plant kingdom and are involved in plant development and stress response. In this study, 9 PRP genes were identified from the apple genome and a comprehensive analysis of the PRP family was conducted, including gene structures, phylogenetic analysis, chromosome mapping, and so on. The expression of MdPRPs varied among tissues and in response to different types of stresses. MdPRP4 and MdPRP7 were induced by five detected stress treatments, including heat, drought, abscisic acid, cold, and salt; the expression patterns of the others varied under different types of stress. Subcellular localization showed that MdPRPs mainly functioned in the cytoplasm, except for MdPRP1 and MdPRP5, which also functioned in the nucleus. When MdPRP6 was overexpressed in tobacco, the transgenic plants showed higher tolerance to high temperature (48 °C) compared with wild-type (WT) plants. The transgenic plants showed milder wilting, a lower accumulation of electrolyte leakage, MDA and ROS, and a higher level of chlorophyll and SOD and POD activity, indicating that MdPRP6 may be an important gene in apples for heat stress tolerance. Overall, this study suggested that MdPRPs are critically important for the ability of apple responses to stresses.


Assuntos
Malus/genética , Proteínas de Plantas , Domínios Proteicos Ricos em Prolina , Estresse Fisiológico , Temperatura Alta , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética , Tabaco/metabolismo
7.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073724

RESUMO

Water deficit adversely affects apple (Malus domestica) productivity on the Loess Plateau. Autophagy plays a key role in plant responses to unfavorable environmental conditions. Previously, we demonstrated that a core apple autophagy-related protein, MdATG8i, was responsive to various stresses at the transcript level. Here, we investigated the function of this gene in the response of apple to severe drought and found that its overexpression (OE) significantly enhanced drought tolerance. Under drought conditions, MdATG8iOE apple plants exhibited less drought-related damage and maintained higher photosynthetic capacities compared with the wild type (WT). The accumulation of ROS (reactive oxygen species) was lower in OE plants under drought stress and was accompanied by higher activities of antioxidant enzymes. Besides, OE plants accumulated lower amounts of insoluble or oxidized proteins but greater amounts of amino acids and flavonoid under severe drought stress, probably due to their enhanced autophagic activities. Particularly, MdATG8iOE plants showed higher root hydraulic conductivity than WT plants did under drought conditions, indicating the enhanced ability of water uptake. In summary, the overexpression of MdATG8i alleviated oxidative damage, modulated amino acid metabolism and flavonoid synthesis, and improved root water uptake, ultimately contributing to enhanced drought tolerance in apple.


Assuntos
Família da Proteína 8 Relacionada à Autofagia/metabolismo , Secas , Malus/metabolismo , Estresse Oxidativo , Estresse Fisiológico , Autofagia , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/fisiologia , Plantas Geneticamente Modificadas
8.
Vector Borne Zoonotic Dis ; 21(1): 63-66, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33170090

RESUMO

Microsporidia are a group of unicellular and opportunistic intestinal parasites in which Enterocytozoon bieneusi is a frequent species causing microsporidial infections in humans. Many domesticated and wild animals have been shown to be hosts of E. bieneusi and other microsporidia. The role of hedgehogs in the ecology of microsporidia is unclear; therefore, we investigated the prevalence and genetic diversity of E. bieneusi, Cryptosporidium, and Blastocystis spp. in hedgehogs (Erinaceus amurensis) collected from Hubei Province in Central China. PCR amplification of the internal transcribed spacer region of the ribosomal DNA indicated that 9.8% (4/41) hedgehogs were positive to E. bieneusi, but none (0/41) was positive to Cryptosporidium and Blastocystis spp. Phylogenetic analysis showed the strains detected from the hedgehogs belong to four novel genotypes (EA1-EA4), which were most closely related to type IV of group 1c. This study demonstrated that hedgehogs are hosts of E. bieneusi and may play a role in the transmission of E. bieneusi to humans in the process of being caught and slaughtered.

9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 1012-1024, 2020 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-33369340

RESUMO

With the increasing global burden of various cancer, an abundance of papers emerged every year in the research hotspots of oncology, covering a wide range of research types and topics. In order to facilitate interested readers to quickly grasp the frontier and hotspots of cancer research, it would be helpful to sort out and summarize the research topic in a timely manner. According to the classification of disciplines, we screened the Essential Science Indicators (ESI) hot papers released in 2019 for the ones in the oncology field, utilized methods such as bibliometrics, statistical description, hierarchical induction, analysis and interpretation to further reveal the context and characteristics of research in the field of oncology, summarized the latest progresses and future directions in the field, and provided information and hints for the trajectory of future research. A total of 549 papers were included, which were mainly from the field of clinical medicine; the country with the most publications was the United States, while China ranked the fourth in terms of contribution; the research institution with the highest number of published papers was University of Texas system; N Engl J Med published the most papers, with contribution also from highly influential journals in the field of oncology such as Lancet Oncol, J Clin Oncol, JAMA Oncol and Cancer Discov. Oncology remained the most popular research topic in the medical research and spanned a wide spectrum of sub-topics. In this study, we demonstrated and sorted out research frontiers in the field of oncology in 12 different research directions including the basic cancer research, cancer epidemiology, and various tumors types related to different systems and organs.


Assuntos
Bibliometria , Pesquisa Biomédica , China , Humanos , Neoplasias , Publicações , Estados Unidos
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 741-748, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140596

RESUMO

With the heavier burden of cardiovascular disease, an abundance of papers emerge every year in the research hotspots, which cover a wide range of types and content. In order to let readers interested in the cardiovascular field quickly understand the research hotspots and research frontier, it is necessary to sort out and summarize the research topic in time. According to the discipline classification, we screened papers in cardiovascular field from the Essential Science Indicators (ESI) hot papers published in 2019. Methods such as bibliometrics, statistical description, hierarchical induction, analysis and interpretation were used a step further to reveal the context and characteristics of research in the field of cardiovascular diseases, summarize the latest progress and development direction in this field, and provide information and hints for the expansion of future research directions. A total of 297 papers were finally included, which were mainly in the field of clinical medicine; The country with the most publications was the United States, while China ranked the fifth in terms of contribution; the research institution with the highest number of published papers was Harvard University; the New England Journal of Medicine (NEJM) has published the most papers, with contribution also from journals such as Circulation, Europe Heart Journal, JAMA, and Lancet. All the papers were categorized into disease burden, disease risk, drug treatment, device treatment and surgical treatment, clinical diagnosis, basic research and others, so as to review and summarize the research front in the field of cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Bibliometria , China , Humanos , Estados Unidos
11.
Plant Sci ; 301: 110654, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33218625

RESUMO

Myo-inositol and its derivatives play vital roles in plant stress tolerance. Myo-inositol-1-phosphate synthase (MIPS) is the rate-limiting enzyme of myo-inositol biosynthesis. However, the role of apple MIPS-mediated myo-inositol biosynthesis in stress tolerance remains elusive. In this study, we found that ectopic expression of MdMIPS1 from apple increased myo-inositol content and enhanced tolerance to salt and osmotic stresses in transgenic Arabidopsis lines. In transgenic apple lines over-expressing MdMIPS1, the increased myo-inositol levels could promote accumulation of other osmoprotectants such as glucose, sucrose, galactose, and fructose, to alleviate salinity-induced osmotic stress. Also, it was shown that overexpression of MdMIPS1 enhanced salinity tolerance by improving the antioxidant system to scavenge ROS, as well as Na+ and K+ homeostasis. Taken together, our results revealed a protective role of MdMIPS1-mediated myo-inositol biosynthesis in salt tolerance by improving osmotic balance, antioxidant defense system, and ion homeostasis in apple.


Assuntos
Antioxidantes/metabolismo , Malus/genética , Mio-Inositol-1-Fosfato Sintase/metabolismo , Tolerância ao Sal/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Inositol/metabolismo , Íons/metabolismo , Malus/fisiologia , Mio-Inositol-1-Fosfato Sintase/genética , Osmose , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Salinidade , Estresse Fisiológico
12.
Hortic Res ; 7: 138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922810

RESUMO

As a versatile compound, myo-inositol plays vital roles in plant biochemistry and physiology. We previously showed that exogenous application of myo-inositol had a positive role in salinity tolerance in Malus hupehensis Rehd. In this study, we used MdMIPS (the rate-limiting gene of myo-inositol biosynthesis) transgenic apple lines to gain new insights into the physiological role of myo-inositol in apple. Decreasing myo-inositol biosynthesis in apple lines by RNA silencing of MdMIPS1/2 led to extensive programmed cell death, which manifested as necrosis of both the leaves and roots and, ultimately, plant death. Necrosis was directly caused by the excessive accumulation of reactive oxygen species, which may be closely associated with the cell wall polysaccharide-mediated increase in salicylic acid and a compromised antioxidant system, and this process was enhanced by an increase in ethylene production. In addition, a high accumulation of sorbitol promoted necrosis. This synergetic interplay between salicylic acid and ethylene was further supported by the fact that increased myo-inositol accumulation significantly delayed leaf senescence in MdMIPS1-overexpressing apple lines. Taken together, our results indicated that apple myo-inositol regulates reactive oxygen species-induced programmed cell death through salicylic acid-dependent and ethylene-dependent pathways.

13.
Plant Sci ; 299: 110611, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32900448

RESUMO

Abiotic stresses threaten the productivity and quality of economically important perennial fruit crops such as apple (Malus × domestica Borkh.). WRKY transcription factors play various roles in plant responses to abiotic stress, but little is known regarding WRKY genes in apple. Here, we carried out functional characterization of an apple Group IIa WRKY gene (MdWRKY30). qRT-PCR analysis found that MdWRKY30 expression was induced by salt and drought stress. A subcellular localization assay showed that MdWRKY30 is localized to the nucleus. A transactivation assay found that MdWRKY30 has no transcriptional activation activity. A Y2H assay indicated that MdWRKY26, MdWRKY28, and MdWRKY30 interact with each other to form heterodimers and homodimers. Transgenic analysis revealed that the overexpression of MdWRKY30 in Arabidopsis enhanced salt and osmotic tolerance in the seedling stage, as well as during the seed germination and greening cotyledon stages. MdWRKY30 overexpression enhanced tolerance to salt and osmotic stresses in transgenic apple callus through transcriptional regulation of stress-related genes. Together, our results demonstrate that MdWRKY30 is an important regulator of salinity and osmotic stress tolerance in apple.


Assuntos
Arabidopsis/fisiologia , Malus/fisiologia , Pressão Osmótica , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Arabidopsis/genética , Malus/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
14.
Plant Physiol Biochem ; 154: 689-698, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32750646

RESUMO

Myo-inositol is a versatile compound and plays a vital role in plant growth and stress tolerance. Previously, we found that exogenous application of myo-inositol enhanced the salinity tolerance in Malus hupehensis Rehd. by enhancing myo-inositol metabolism. In this study, we found that the tonoplast-localized myo-inositol transporter 1 (MdINT1) was involved in myo-inositol accumulation and conferred salinity tolerance in apple. MdINT1 is characterized by the highest transcripts among the four apple INT-like genes and could be induced by salt stress at the transcriptional level. Also, it was shown that myo-inositol level was slightly decreased in the leaves of transgenic apple lines over-expressing MdINT1, but was significantly increased in the leaves and roots of MdINT1 silencing line. Interestingly, overexpression of MdINT1 enhanced salinity tolerance by promoting Na+ and K+ balance, antioxidant activity, and accumulation of osmoprotectants in transgenic apple lines. In contrast, under salinity conditions, the MdINT1-mediated protective roles in the antioxidant activity, homeostasis of ions and osmosis were compromised, which in turn increased the risk of salt intolerance in the MdINT1 silencing line.


Assuntos
Antioxidantes/fisiologia , Inositol/metabolismo , Malus/fisiologia , Proteínas de Transporte de Monossacarídeos/fisiologia , Proteínas de Plantas/fisiologia , Tolerância ao Sal , Regulação da Expressão Gênica de Plantas , Homeostase , Íons/metabolismo , Malus/genética , Osmose , Plantas Geneticamente Modificadas , Salinidade
15.
Front Plant Sci ; 11: 423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351530

RESUMO

Autophagy is an efficient degradation system for maintaining cellular homeostasis when plants are under environmental stress. ATG9 is the only integral membrane protein within the core ATG machinery that provides a membrane source for autophagosome formation. In this study, we isolated an ATG9 homologs gene in apple, MdATG9, from Malus domestica. The analysis of its sequence, subcellular localization, promoter cis-elements, and expression patterns revealed the potential function of MdATG9 in response to abiotic stressors. Overexpression of MdATG9 in apple callus conferred enhanced tolerance to nitrogen depletion stress. During the treatment, other important MdATGs were expressed at higher levels in transgenic callus than in the wild type. Furthermore, more free amino acids and increased sucrose levels were found in MdATG9-overexpression apple callus compared with the wild type in response to nitrogen starvation, and the expression levels of MdNRT1.1, MdNRT2.5, MdNIA1, and MdNIA2 were all increased higher in transgenic lines. These data suggest that, as an important autophagy gene, MdATG9 plays an important role in the maintenance of amino acids and sugars in response to nutrient starvation in apple.

16.
Plant Sci ; 294: 110444, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32234232

RESUMO

Autophagy is a conserved pathway to degrade and recycle damaged proteins and organelles, which has generally been reported to play an important role in plant adaption to various abiotic stressors. Here, we isolated a new apple autophagy-related gene, MdATG10, from Malus domestica. Expression of MdATG10 was induced by salt stress, particularly in roots. To investigate the effects of increased autophagic activity on salt tolerance of apple, we generated three MdATG10-overexpressing apple lines and exposed them to salt stress. The transgenic apple plants exhibited enhanced salt tolerance, accompanied by slightly damaged photosynthetic ability and a milder growth limitation under the salt treatment. In addition, damage to growth and vitality of the root system caused by the salt treatment was alleviated by overexpressing MdATG10. Furthermore, reduced accumulation of Na+ and a lower Na+: K+ ratio was detected in the MdATG10-overexpressing apple lines under salt stress. The salt treatment induced expression of genes involved in ion homeostasis in transgenic apple roots. These results demonstrate a promoting role of autophagy in ion transport when plants encounter salty conditions.


Assuntos
Malus/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Canais Iônicos/metabolismo , Malus/efeitos dos fármacos , Malus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal/efeitos dos fármacos , Tolerância ao Sal/genética , Sódio/metabolismo
17.
Vector Borne Zoonotic Dis ; 20(8): 580-585, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32301684

RESUMO

Coxiella burnetii is the causative agent of query fever (Q fever), and distributes broadly in environment. Livestock are identified as main reservoirs, which may infect people through their contaminative urine, feces, milk, and birth products. Wild animals can also be the potential carriers and transmitters of C. burnetii. To understand the geographic distribution and host species of C. burnetii in China, we investigated the prevalence of C. burnetii in hedgehogs (Erinaceus amurensis) in Hubei Province. Hedgehogs were tested for C. burnetii with PCR targeting three genes (com1, rrs, and icd) followed by multispacer sequence typing (MST). We found that 12.2% (5/41) hedgehogs were PCR positive for C. burnetii. MST revealed presence of two novel genotypes and phylogenetic analysis revealed that the strains were similar to a group of isolates from chronic Q fever patients and mammals. This study showed that C. burnetii are highly prevalent in hedgehogs in Hubei Province in central China, suggesting that hedgehogs may play an important role in the ecology and transmission of C. burnetii to humans because it is captured and used as traditional medicine in China.


Assuntos
Coxiella burnetii/isolamento & purificação , Ouriços-Cacheiros/microbiologia , Febre Q/veterinária , Animais , China/epidemiologia , Coxiella burnetii/classificação , Coxiella burnetii/genética , DNA Bacteriano , Genótipo , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Febre Q/epidemiologia
18.
Hortic Res ; 7: 21, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32140230

RESUMO

High temperature is an abiotic stress factor that threatens plant growth and development. Autophagy in response to heat stress involves the selective removal of heat-induced protein complexes. Previously, we showed that a crucial autophagy protein from apple, MdATG18a, has a positive effect on drought tolerance. In the present study, we treated transgenic apple (Malus domestica) plants overexpressing MdATG18a with high temperature and found that autophagy protected them from heat stress. Overexpression of MdATG18a in apple enhanced antioxidase activity and contributed to the production of increased beneficial antioxidants under heat stress. Transgenic apple plants exhibited higher photosynthetic capacity, as shown by the rate of CO2 assimilation, the maximum photochemical efficiency of photosystem II (PSII), the effective quantum yield, and the electron transport rates in photosystems I and II (PSI and PSII, respectively). We also detected elevated autophagic activity and reduced damage to chloroplasts in transgenic plants compared to WT plants. In addition, the transcriptional activities of several HSP genes were increased in transgenic apple plants. In summary, we propose that autophagy plays a critical role in basal thermotolerance in apple, primarily through a combination of enhanced antioxidant activity and reduced chloroplast damage.

19.
Vector Borne Zoonotic Dis ; 20(6): 427-431, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155388

RESUMO

Background: Leptospira is the causative agent of leptospirosis, a zoonotic disease of global importance. To have a better understanding on the host species of Leptospira, we investigated the prevalence of Leptospira species in hedgehogs in Central China. Materials and Methods: Hedgehogs were captured in Hubei Province, China in May and October, 2018. Total DNA was extracted from the kidney tissues of hedgehogs for determining the Leptospira species by PCR amplification of the rrs2, secY, and flaB genes with genus-specific primers. Results: PCR amplification indicated that the positive rate of hedgehogs to the rrs2, secY, and flaB genes were 19.5% (8/41), 12.2% (5/41), and 9.8% (4/41), respectively. The homology of the partial sequence of rrs2, secY, and flaB genes were 99.0-100% among the Leptospira strains from hedgehogs. Phylogenetic analysis revealed that Leptospira species detected in this study clustered together with Leptospira interrogans. Conclusions: We detected L. interrogans from hedgehogs in Central China, suggesting hedgehogs are the hosts of L. interrogans.


Assuntos
Ouriços-Cacheiros/microbiologia , Leptospira interrogans/isolamento & purificação , Leptospirose/veterinária , Animais , China/epidemiologia , DNA Bacteriano/genética , Rim/microbiologia , Leptospira interrogans/genética , Leptospirose/epidemiologia , Leptospirose/microbiologia , Filogenia , Prevalência
20.
J Drug Target ; 28(3): 245-258, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31462111

RESUMO

Conventional treatment fails to completely eliminate highly invasive breast cancer cells, and most surviving breast cancer cells tend to reproliferate and metastasize by forming vasculogenic mimicry (VM) channels. Thus, a type of targeted liposomes was developed by modification with arginine8-glycine-aspartic acid (R8GD) to encapsulate daunorubicin and emodin separately. A combination of the two targeted liposomes was then developed to destroy VM channels and inhibit tumour metastasis. MDA-MB-435S cells, a highly invasive breast cancer, were then evaluated in vitro and in mice. The experiments indicated that R8GD modified daunorubicin liposomes plus R8GD modified emodin liposomes had small particle size, uniform particle size distribution and high drug encapsulation rate. The combination of the two targeted liposomes exerted strong toxicity on the MDA-MB-435S cells and effectively inhibited the formation of VM channels and the metastasis of tumour cells. Action mechanism studies showed that the R8GD modified daunorubicin liposomes plus R8GD modified emodin liposomes could downregulate some metastasis-related proteins, including MMP-2, VE-cad, TGF-ß1 and HIF-1α. These studies also demonstrated that the targeted liposomes allowed the chemotherapeutic drug to selectively accumulate at tumour site, thus exhibiting a distinct antitumor effect. Therefore, the combination of targeted daunorubicin liposomes and targeted emodin liposomes can provide a potential treatment for invasive breast cancer.

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