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1.
Virology ; 540: 141-149, 2019 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-31794888

RESUMO

In recent years, Sri Lankan cassava mosaic virus (SLCMV), a begomovirus (genus Begmovirus, family Geminiviridae) causing cassava mosaic disease in Asia, poses serious threats to cassava cultivation in Asia. However, the transmission of SLCMV in the areas into which it has recently been introduced remain largely unexplored. Here we have compared the transmission efficiencies of SLCMV by three widely distributed whitefly species in Asia, and found that only Asia II 1 whiteflies were able to transmit this virus efficiently. The transmission efficiencies of SLCMV by different whitefly species were found to correlate positively with quantity of virus in whitefly whole body. Further, the viral transmission efficiency was found to be associated with varied ability of virus movement within different species of whiteflies. These findings provide detailed information regarding whitefly transmission of SLCMV, which will help to understand the spread of SLCMV in the field, and facilitate the prediction of virus epidemics.

2.
Cancer Lett ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31765737

RESUMO

Most cancers are caused by somatic mutations. Some common mutations in the same cancer type can form a "signature" to specifically predict the prognosis or to distinguish it from other cancers. In this study, 710 somatic cell mutations were identified in 142 cases, including digestive, lung and urogenital cancers, and the digestive cancers were further divided into liver, stomach, intestinal, esophageal and cardia cancer. The above mutations were located in 166 genes. In addition, a group of high-frequency mutation genes with specific characteristics were screened to form predictive signatures for each cancer. Verification using TCGA suggested that the signatures could predict the stages, progression-free survival, and overall survival of digestive, intestinal, and liver cancers (P < 0.05). The validation cases further confirmed the predictive role of digestive and liver cancers signatures in diagnosis and prognosis. Overall, this study established predictive signatures for different cancer systems and their subtypes. These findings enable a better understanding in cancer genome, and contribute to the personalized diagnosis and treatment.

3.
Cell Cycle ; 18(19): 2432-2446, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31448674

RESUMO

Prostate cancer (PCa) is a frequently occurring malignancy in males, and epithelial mesenchymal transition (EMT) plays a critical role in PCa metastasis. Thus, developing biomarkers inhibiting EMT may provide significance for treatment of PCa. Hence, the aim of the current study was to investigate the mechanism by which FBP1 gene silencing influences PCa cell EMT, invasion and metastasis by mediating the MAPK pathway. PCa cell lines exhibiting the highest FBP1 expression were selected and treated with plasmids of siRNA-FBP1 sequence 1 and 2, pcDNA3.1-Flag-FBP1 (over-expression plasmid of FBP1), U0126 (an inhibitor of the ERK signaling pathway) and PD98059 (an inhibitor of the MEK signaling pathway). Cell proliferation, migration and invasion were detected by MTT assay, wound healing assay and Transwell assay, respectively. The mRNA and protein expression of related factors of EMT and MAPK signaling were determined by RT-qPCR and western blot analysis, respectively. Xenograft tumor growth after inoculation of DU145 cells was regularly analyzed in the nude mice. The positive expression of EMT markers was determined by immunohistochemistry. DU-145 and PC-3 cells displaying the highest FBP1 expression were selected for further analysis. The PCa cells treated with siRNA-FBP1 exhibited increased proliferation, migration rate and invasion, in addition to facilitated xenograft tumor growth. Notably, siRNA-FBP1 was identified to accelerate PCa cell EMT by elevating the expression of Vimentin and N-cadherin while diminishing E-cadherin expression via activation of the MAPK signaling pathway. The aforementioned results were reversed in PCa cells treated by pcDNA3.1-Flag-FBP1. Evidence has been provided in this study that FBP1 gene silencing activates the MAPK pathway, which ultimately promotes cell EMT, invasion and metastasis in PCa.

4.
Pathol Res Pract ; 215(10): 152553, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31362888

RESUMO

BACKGROUND: Nidogen-2 (NID2) is a ubiquitous component in the basement membrane and plays an important role in the development of malignant tumors. However, the specific function and mechanism of the NID2 gene in gastric cancer remains unclear. In this study, we aimed to investigate the role of NID2 in gastric cancer(GC). METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of NID2 in 67 GC tissues and adjacent normal tissues. The relationship between NID2 expression and clinicopathological features was further analyzed. In addition, we evaluated the expression of NID2 in GC based on data from the GEPIA and Kaplan-Meier Plotter database and compared the database results with our own experimental results. Invasion and wound healing assays were used to detect the function of NID2 in MKN45 and SGC7901 cells. Finally, the NID2 network and its possible related genes are constructed by the bioinformatics framework. RESULTS: The expression level of NID2 was found to be significantly over-expressed in gastric cancer cells and tissues compared with normal controls and positively associated with TNM stage, showing a poor prognosis of GC patients. In vitro experiments indicated that NID2 was able to promote the ability of invasion and migration in GC cells. Bioinformatics prediction showed NID2 might regulate the progression of GC via protein digestion and absorption, amoebiasis, PI3K-AKt-signaling pathway, focal adhesion and ECM-receptor interaction pathways. CONCLUSION: Our study demonstrates that up-regulated NID2 plays an important role in promoting the invasion and migration of GC cells and has a potential of being a novel biomarker for diagnosis, treatment and prognosis of GC in the future.

5.
Virology ; 535: 210-217, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31319278

RESUMO

Tomato yellow leaf curl virus (TYLCV) poses serious threat to tomato production worldwide, and the vector, Bemisia tabaci, plays a key role in the transmission of this virus. However, the molecular mechanisms underlying the transmission remain poorly understood. In this study, firstly, we identified the whitefly proteins that presumably interact with TYLCV coat protein (CP) using split-ubiquitin yeast two-hybrid system. Next, we conducted GST pull-down and immunofluorescence to examine the potential interaction between TYLCV CP and one of the proteins identified, namely vesicle associated membrane protein-associated protein B (VAPB), an protein abundantly expressed in whitefly midgut. Further experiments demonstrated that VAPB was significantly up-regulated upon virus acquisition, and silencing VAPB led to a significant increase of relative virus quantity in whitefly haemolymph and salivary glands, as well as an increase of TYLCV transmission efficiency. These findings indicate an important role of VAPB in the transmission of TYLCV by whiteflies.

6.
Methods Mol Biol ; 2033: 287-300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31332761

RESUMO

The emergence of "molecular superglue," such as SpyTag-SpyCatcher chemistry, has tremendously expanded our capability in manipulating protein shape and architecture via conjugation. Telechelic proteins bearing the SpyTag and SpyCatcher reactive sequences can be expressed and purified for bioconjugation in vitro, giving protein conjugates, branched proteins, and circular proteins. By encoding both reactive sequences in the same construct for expression in vivo, the nascent protein undergoes programmed posttranslational modification guided by protein folding and reaction, leading to diverse nonlinear topologies in situ. In this chapter, we present the SpyTag-SpyCatcher chemistry as a versatile platform for protein bioconjugation and topology engineering.

8.
J Drug Target ; : 1-10, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31244351

RESUMO

In recent years, the rate of colorectal cancer has sharply increased, especially in China, where it ranks second for the number of cancer fatalities. Currently, the treatment of colorectal cancer patients involves the combination of resection surgery and treatment with postoperative anticancer drugs such as 5-FU and oxaliplatin. However, recurrence and metastasis after treatment are still the dominant reasons for the low survival rate. Colorectal cancer stem cells (CSCs) are regarded as the key contributors to tumour recurrence and metastasis due to their resistance to chemotherapy drugs and their extremely high tumourigenicity. Once CSCs overcome chemotherapy treatment, they continue to survive and reinitiate proliferation to form tumours, leading to recurrence. The dominant reason for CSC resistance is that most anticancer drugs are aimed at inhibiting proliferative pathways in cancer cells that differ from those in CSCs. Therefore, studies on the characteristics of CSCs and their intracellular molecular pathways are essential for the exploration of CSC-targeted drugs. In this report, we review recent advances in the research of CSCs and, in particular, review the important intracellular molecular pathways, such as HOXA5-catenin, STRAP-NOTCH and YAP/TAZ, related to the maintenance and differentiation of stem cells to generate a theoretical basis for the exploration of CSC-targeted drugs.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 104-109, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31030037

RESUMO

Sodium nitrate as an important inorganic component can be chemically formed from the reactions of nitrogen oxides and nitric acid (HNO3) with sea salt in atmosphere. Organic acids contribute a significant fraction of photochemical formed secondary organics that can condense on the preexisting nitrate-containing particles. Atmospheric particles often include a complex mixture of nitrate and secondary organic materials accumulated within the same individual particles. Here we studied the hygroscopicity of aerosol particles composed of sodium nitrate and glutaric acid (GA) by using a pulsed RH controlling system and a rapid scan vacuum FTIR spectrometer (PRHCS-RSVFTIR). The water content in the particles and efflorescence ratios of both NaNO3 and GA at ambient relative humidity (RH) as a function of time were obtained from the rapid-scan infrared spectra with a sub-second time resolution. Our study showed that both NaNO3 and GA crystallized at 44.1% RH during two different RH control processes (stepwise and pulsed processes). It was found that the addition of GA could suppress the efflorescence of NaNO3 during the dehumidifying process. In addition, the mixed NaNO3/GA particles release HNO3 during the dehumidifying and humidifying cycles. These findings are important in further understanding the role of interactions between water-soluble dicarboxylic acids and nitrates on hygroscopicity and environmental effects of atmospheric particles.

10.
Virology ; 531: 240-247, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30933715

RESUMO

Begomoviruses contain some of the most damaging viral disease agents of crops worldwide, and are transmitted by whiteflies of the Bemisia tabaci species complex. During the last 20 years, transovarial transmission of tomato yellow leaf curl virus (TYLCV) has been reported in two invasive species of the B. tabaci complex. To further decipher the importance of this mode of transmission, we analyzed transovarial transmission of TYLCV by seven whitefly species indigenous to China. TYLCV virions were detected in eggs of all species except one, and in nymphs of two species, but in none of the ensuing adults of all seven species. Our results suggest that these indigenous whiteflies are unable to transmit TYLCV, a begomovirus alien to China, via ova to produce future generations of viruliferous adults, although most of the species exhibit varying ability to carry over the virus to the eggs/nymphs of their offspring via transovarial transmission.


Assuntos
Begomovirus/fisiologia , Hemípteros/fisiologia , Hemípteros/virologia , Insetos Vetores/fisiologia , Insetos Vetores/virologia , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Animais , China , Hemípteros/classificação , Hemípteros/genética , Insetos Vetores/classificação , Insetos Vetores/genética
11.
Sci Rep ; 9(1): 6568, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31024030

RESUMO

The 37 currently recognized Bemisia tabaci cryptic species are economically important species and contain both primary and secondary endosymbionts, but their diversity has never been mapped systematically across the group. To achieve this, PacBio sequencing of full-length bacterial 16S rRNA gene amplicons was carried out on 21 globally collected species in the B. tabaci complex, and two samples from B. afer were used here as outgroups. The microbial diversity was first explored across the major lineages of the whole group and 15 new putative bacterial sequences were observed. Extensive comparison of our results with previous endosymbiont diversity surveys which used PCR or multiplex 454 pyrosequencing platforms showed that the bacterial diversity was underestimated. To validate these new putative bacteria, one of them (Halomonas) was first confirmed to be present in MED B. tabaci using Hiseq2500 and FISH technologies. These results confirmed PacBio is a reliable and informative venue to reveal the bacterial diversity of insects. In addition, many new secondary endosymbiotic strains of Rickettsia and Arsenophonus were found, increasing the known diversity in these groups. For the previously described primary endosymbionts, one Portiera Operational Taxonomic Units (OTU) was shared by all B. tabaci species. The congruence of the B. tabaci-host and Portiera phylogenetic trees provides strong support for the hypothesis that primary endosymbionts co-speciated with their hosts. Likewise, a comparison of bacterial alpha diversities, Principal Coordinate Analysis, indistinct endosymbiotic communities harbored by different species and the co-divergence analyses suggest a lack of association between overall microbial diversity with cryptic species, further indicate that the secondary endosymbiont-mediated speciation is unlikely to have occurred in the B. tabaci species group.

12.
Virol J ; 16(1): 32, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30857562

RESUMO

BACKGROUND: Viruses in the genus Begomovirus (Family Geminiviridae) include many important economic plant viruses transmitted by whiteflies of the Bemisia tabaci species complex. In general, different begomoviruses may be acquired and transmitted by the same whitefly species with different efficiencies. For example, the species Mediterranean (MED) in this whitefly species complex transmits tomato yellow leaf curl virus (TYLCV) at a higher efficiency than papaya leaf curl China virus (PaLCuCNV). However, the proteomic responses of whitefly to the infection of different begomoviruses remain largely unknown. METHODS: We used iTRAQ-based proteomics coupled with RT-qPCR to investigate and compare responses of the MED whitefly to the infection of TYLCV and PaLCuCNV. RESULTS: Totally, 259, 395 and 74 differently expressed proteins (DEPs) were identified in the comparisons of TYLCV-infected vs. un-infected, PaLCuCNV-infected vs. un-infected, and TYLCV-infected vs. PaLCuCNV-infected whiteflies, respectively. These proteins appear associated with catabolic process, metabolic process, transport, defense response, cell cycle, and receptor. The comparisons of TYLCV-infected vs. un-infected and PaLCuCNV-infected vs. un-infected shared some similar DEPs, indicating possible involvement of laminin subunit alpha, dystroglycan, integrin alpha-PS2 and cuticle proteins in viral transport as well as the role of putative defense proteins 3 and PITH in anti-viral response. However, 20S proteasome subunits associated with regulation of virus degradation and accumulation were up-regulated in PaLCuCNV-infected but not in TYLCV-infected whiteflies, which may be related to the constraints of PaLCuCNV accumulation in MED. CONCLUSIONS: These findings provide valuable clues for unravelling the roles of some whitefly proteins in begomovirus transmission.


Assuntos
Begomovirus/genética , Hemípteros/virologia , Interações entre Hospedeiro e Microrganismos/genética , Proteômica/métodos , Viroses/transmissão , Animais , Doenças das Plantas/virologia , Vírus de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real
13.
PLoS Pathog ; 15(2): e1007607, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30789967

RESUMO

Most plant viruses are vectored by insects and the interactions of virus-plant-vector have important ecological and evolutionary implications. Insect vectors often perform better on virus-infected plants. This indirect mutualism between plant viruses and insect vectors promotes the spread of virus and has significant agronomical effects. However, few studies have investigated how plant viruses manipulate plant defenses and promote vector performance. Begomoviruses are a prominent group of plant viruses in tropical and sub-tropical agro-ecosystems and are transmitted by whiteflies. Working with the whitefly Bemisia tabaci, begomoviruses and tobacco, we revealed that C2 protein of begomoviruses lacking DNA satellites was responsible for the suppression of plant defenses against whitefly vectors. We found that infection of plants by tomato yellow leaf curl virus (TYLCV), one of the most devastating begomoviruses worldwide, promoted the survival and reproduction of whitefly vectors. TYLCV C2 protein suppressed plant defenses by interacting with plant ubiquitin. This interaction compromised the degradation of JAZ1 protein, thus inhibiting jasmonic acid defense and the expression of MYC2-regulated terpene synthase genes. We further demonstrated that function of C2 protein among begomoviruses not associated with satellites is well conserved and ubiquitination is an evolutionarily conserved target of begomoviruses for the suppression of plant resistance to whitefly vectors. Taken together, these results demonstrate that ubiquitination inhibition by begomovirus C2 protein might be a general mechanism in begomovirus, whitefly and plant interactions.


Assuntos
Begomovirus/metabolismo , Hemípteros/metabolismo , Animais , Begomovirus/patogenicidade , Ciclopentanos/metabolismo , Hemípteros/virologia , Insetos Vetores/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/virologia , Vírus de Plantas/patogenicidade , Simbiose , Tabaco/virologia , Ubiquitinação
14.
Curr Microbiol ; 76(4): 442-447, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30758644

RESUMO

A Gram-stain negative, strictly aerobic, non-spore forming, non-motile, rod-shaped bacterium, designated TBBPA-24T, was isolated from tetrabromobisphenol A-contaminated soil in China. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain TBBPA-24T was most closely related to Pedobacter nanyangensis Q4T (96.5%) and Pedobacter 'zeaxanthinifaciens' TDMA-5T (96.1%). Chemotaxonomic analysis revealed that strain TBBPA-24T possessed MK-7 as the major respiratory quinone and lipid, aminolipid, phospholipid, phosphatidylethanolamine, and phosphoaminolipid as the major polar lipid. The major fatty acids were iso-C15:0 (40.2%), summed feature 3 (C16:1ω6c and/or C16:1ω7c, 25.6%) and iso-C17:0 3-OH (16.4%). The genomic DNA G+C content of strain TBBPA-24T was 43.9 mol%. Based on the phylogenetic, phenotypic characteristics, and chemotaxonomic data, strain TBBPA-24T is considered a novel species of the genus Pedobacter, for which the name Pedobacter pollutisoli sp. nov. is proposed. The type strain TBBPA-24T (= KCTC 62314T = CCTCC AB 2017244T) is proposed.


Assuntos
Pedobacter/classificação , Pedobacter/fisiologia , Filogenia , Bifenil Polibromatos/química , Microbiologia do Solo , Poluentes do Solo/química , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Pedobacter/química , Pedobacter/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo/química , Especificidade da Espécie , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
J Int Med Res ; 47(2): 962-972, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30621488

RESUMO

OBJECTIVE: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a pro-apoptotic ligand that activates the extrinsic apoptosis pathway of cell death receptors. This study aimed to evaluate the relationship between TRAIL and platelet-induced tumor metastasis in colorectal cancer. METHODS: Platelet P-selectin (CD62P) was measured by immunohistochemistry in tumor and adjacent normal tissues from 90 patients with colorectal cancer undergoing resection. Tumor cell invasion was assessed by transwell assay in the presence of platelets with or without TRAIL. The expression of TRAIL receptors DR4 and DR5 on platelets was assessed by flow cytometry, real-time polymerase chain reaction, and western blotting. RESULTS: P-selectin (CD62P) expression was significantly increased in tumor tissues compared with adjacent normal tissues. High CD62P expression was significantly correlated with tumor stage and vascular invasion. Tumor cell migration was increased by coculture with platelets, but this effect was inhibited by TRAIL. Transforming growth factor (TGF)-ß1 secretion was significantly reduced in TRAIL-treated platelets. The TRAIL receptor DR5 but not DR4 was expressed in platelets according to flow cytometry. CONCLUSIONS: TRAIL could inhibit metastasis and colon cancer cell invasion by promoting platelet apoptosis and reducing the release of TGF-ß1.


Assuntos
Plaquetas/patologia , Neoplasias Colorretais/prevenção & controle , Regulação Neoplásica da Expressão Gênica , Selectina-P/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose , Estudos de Casos e Controles , Proliferação de Células , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Selectina-P/genética , Prognóstico , Ligante Indutor de Apoptose Relacionado a TNF/genética , Células Tumorais Cultivadas
17.
Zool Res ; 40(2): 129-138, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30559334

RESUMO

Golden snub-nosed monkeys (Rhinopithecus roxellana), as typical arboreal group-living Old World monkeys, provide an appropriate animal model to research manual laterality and explore the factors affecting hand preference in nonhuman primates. This study investigated hand preference based on 63 subjects and four spontaneous manual tasks (including unimanual and bimanual feeding and grooming), and assessed the effects of age, gender and type of task on handedness in R. roxellana. A population-level left-handedness was found not only in the bimanual coordinated tasks (bimanual feeding and grooming), but also in one unimanual reaching task (unimanual feeding). There were no significant differences between the sexes in either direction or strength of hand preference among any task. However, a significant difference between adults and juveniles was found in the unimanual feeding task. This is the first report on handedness in unimanual and bimanual feeding tasks that require bipedal posture in wild R. roxellana. Furthermore, this study demonstrated spontaneous feeding tasks reported previously only in the quadrupedal posture in this species, supporting the importance of factors such as posture and task complexity in the evolution of primate manual lateralization.


Assuntos
Envelhecimento , Colobinae/fisiologia , Lateralidade Funcional/fisiologia , Animais , Feminino , Masculino , Fatores Sexuais
18.
Int J Mol Med ; 43(2): 980-992, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535467

RESUMO

Our previous studies identified that the expression of microRNA­29c (miR­29c­3p) was significantly increased in the serum of pregnant women carrying fetuses with congenital heart disease (CHD) compared with in that of normal pregnant women. However, the mechanism by which miR­29c­3p affects development of the embryonic heart remained unclear. The aim of the present study was to investigate the effect and potential molecular mechanism of miR­29c­3p overexpression on P19 cell proliferation, apoptosis and differentiation. miR­29c­3p­overexpression and protein kinase Bγ (Akt3)­knockdown cell lines were constructed using transfection technology. The function of miR­29c­3p and Akt3 in cardiomyocyte development was investigated by determining the proliferation, apoptosis and differentiation of P19 cells, which can differentiate into cardiomyocytes induced by dimethylsulfoxide. Bioinformatic analysis and luciferase assays were performed to explore the association between Akt3 and miR­29c­3p. The results of the present study revealed that miR­29c­3p overexpression and Akt3 knockdown suppressed proliferation, and promoted apoptosis and differentiation in P19 cells. Akt3 was also demonstrated to be a target of miR­29c­3p. Therefore, overexpression of miR­29c­3p may inhibit proliferation, and promote apoptosis and differentiation in P19 cells by inhibiting the expression of Akt3. miR­29c­3p may be a potential therapeutic target for the treatment of CHD.


Assuntos
Regulação da Expressão Gênica , Cardiopatias Congênitas/etiologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Animais , Biomarcadores , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Cardiopatias Congênitas/metabolismo , Cardiopatias Congênitas/patologia , Camundongos , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transfecção , Proteína X Associada a bcl-2/metabolismo
19.
Proc Natl Acad Sci U S A ; 116(2): 490-495, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30584091

RESUMO

Phloem-feeding insects feed on plant phloem using their stylets. While ingesting phloem sap, these insects secrete saliva to circumvent plant defenses. Previous studies have shown that, to facilitate their feeding, many phloem-feeding insects can elicit the salicylic acid- (SA-) signaling pathway and thus suppress effective jasmonic acid defenses. However, the molecular basis for the regulation of the plant's defense by phloem-feeding insects remains largely unknown. Here, we show that Bt56, a whitefly-secreted low molecular weight salivary protein, is highly expressed in the whitefly primary salivary gland and is delivered into host plants during feeding. Overexpression of the Bt56 gene in planta promotes susceptibility of tobacco to the whitefly and elicits the SA-signaling pathway. In contrast, silencing the whitefly Bt56 gene significantly decreases whitefly performance on host plants and interrupts whitefly phloem feeding with whiteflies losing the ability to activate the SA pathway. Protein-protein interaction assays show that the Bt56 protein directly interacts with a tobacco KNOTTED 1-like homeobox transcription factor that decreases whitefly performance and suppresses whitefly-induced SA accumulation. The Bt56 orthologous genes are highly conserved but differentially expressed in different species of whiteflies. In conclusion, Bt56 is a key salivary effector that promotes whitefly performance by eliciting salicylic acid-signaling pathway.


Assuntos
Hemípteros/metabolismo , Herbivoria/fisiologia , Ácido Salicílico/metabolismo , Saliva/metabolismo , Transdução de Sinais/fisiologia , Animais , Proteínas de Homeodomínio/metabolismo , Proteínas de Plantas/metabolismo
20.
Biomed Res Int ; 2018: 1683414, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30533427

RESUMO

Objective: Melasma is a highly prevalent, chronic, and pigmentary disorder. This systematic review aims to evaluate the efficacy and safety of tranexamic acid (TA) for the treatment of adults with melasma. Methods: We independently searched 3 databases from beginning to 26 April, 2018. The study included 21 eligible trials. Two writers extracted data at the same time independently. Study outcomes were calculated by standardized mean differences (SMD) with 95% confidence intervals (CIs). All statistical analyses were performed using Review Manager Version 5.3 and STATA Version 15.1. Results: The combined results showed that the use of TA was associated with reduced Melasma Area and Severity Index (MASI) and Melanin Index (MI). No significant difference in Erythema Index (EI) was observed with TA treatment. Side effects were minor, with a few cases reporting mild gastrointestinal reaction, oligomenorrhoea, hypopigmentation, urticarial rash, and skin irritation xerosis. Conclusion: The meta-analysis suggested that TA treatment appeared to be a promising therapeutic approach for melasma.


Assuntos
Melanose/tratamento farmacológico , Ácido Tranexâmico/uso terapêutico , Adolescente , Adulto , Estudos de Casos e Controles , Eritema , Humanos , Melaninas/metabolismo , Pessoa de Meia-Idade , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Adulto Jovem
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