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1.
Sci Total Environ ; 731: 139178, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32388162

RESUMO

The COVID-19 pandemic is creating a havoc situation across the globe that modern society has ever seen. Despite of their paramount importance, the transmission routes of SARS-Cov-2 still remain debated among various sectors. Evidences compiled here strongly suggest that the COVID-19 could be transmitted via air in inadequately ventilated environments. Existing experimental data showed that coronavirus survival was negatively impacted by ozone, high temperature and low humidity. Here, regression analysis showed that the spread of SARS-Cov-2 was reduced by increasing ambient ozone concentration level from 48.83 to 94.67 µg/m3 (p-value = 0.039) and decreasing relative humidity from 23.33 to 82.67% (p-value = 0.002) and temperature from -13.17 to 19 °C) (p-value = 0.003) observed for Chinese cities during Jan-March 2020. Besides using these environmental implications, social distancing and wearing a mask are strongly encouraged to maximize the fight against the COVID-19 airborne transmission. At no other time than now are the scientists in various disciplines around the world badly needed by the society to collectively confront this disastrous pandemic.


Assuntos
Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Betacoronavirus , Humanos , Pandemias
2.
Pathol Oncol Res ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170580

RESUMO

The radioresistance of oesophageal squamous cell carcinoma (OSCC) is a critical factor leading to a poor prognosis among patients. The expression of PBX1 is abnormally high in a broad range of human tissues, and this gene plays a key role in tumour proliferation. This research intended to explore the radiosensitization of OSCC by silencing PBX1. The OSCC cell lines KYSE450 and KYSE150 were subjected to PBX1 silencing and/or irradiation (IR). Cell proliferation, colony formation, and apoptosis were tested to evaluate the radiosensitization ability of PBX1 silencing. The levels of STAT3 and p-STAT3 in the OSCC cells were tested by Western blotting. Furthermore, KYSE150 cells with or without PBX1 silencing were xenografted into nude mice with or without radiation exposure. Concomitant PBX1 silencing and IR can obviously suppress growth and enhance radiosensitivity in OSCC cells and xenografts. Moreover, the downregulation of PBX1 inhibits the expression of STAT3 and p-STAT3. The downregulation of PBX1 may increase radiosensitivity in OSCC cells and xenografts via the PBX1/STAT3 pathway. Our findings demonstrate that PBX1 may be a potential target for promoting the effect of radiation therapy in OSCC patients.

3.
World J Gastroenterol ; 25(35): 5300-5309, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31558874

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are considered to be highly stable due to the closed structure, which are predominately correlated with the development and progression of a wide variety of cancers. Colon cancer is one of the most common malignancies worldwide. A recent study demonstrated the upregulated expression of circPIP5K1A in non-small cell lung cancer. However, few studies have investigated the relationship between circ_0014130 level and colon cancer. Therefore, elucidating the underlying mechanisms of circPIP5K1A's role may help with the identification of novel diagnostic and therapeutic targets for colon cancer. AIM: To investigate the status of circPIP5K1A in colon cancers and its effects on the modulation of cancer development. METHODS: The expression level of circPIP5K1A in tissue and serum samples from colon cancer patients, as well as human colonic cancer cell lines was detected by real-time quantitative reverse transcription-polymerase chain reaction. Following the transfection of specifically synthesized small interfering RNA (siRNA) into colon cell lines, we used Hoechst staining assay to measure the ratio of cell death in the absence of circPIP5K1A. Moreover, we also used the Transwell assay to assess the migratory function of colon cells overexpressing circPIP5K1A. Additionally, we employed a series of bioinformatics prediction programs to predict the potential of circPIP5K1A-targeted miRNAs and mRNAs. The miR-1273a vector was constructed, and then transfected with or without circPIP5K1A vector into colon cancer cells. Afterwards, the expression of activator protein 1 (AP-1), interferon regulating factor 4 (IRF-4), caudal type homeobox 2 (CDX-2), and zinc finger of the cerebellum 1 (Zic-1) was detected by western blotting. RESULTS: CircPIP5K1A was significantly upregulated in colon cancer tissue relative to their adjacent normal tissues. Knockdown of circPIP5K1A in colon cancer cells impaired cell viability and suppressed cell invasion and migration, while enforced expression of circPIP5K1A exhibited the opposite effects on cell migration. Bioinformatics prediction program predicted that the association of circPIP5K1A with miR-1273a, as well as AP-1, IRF-4, CDX-2, and Zic-1. Subsequent studies showed that overexpression of circPIP5K1A augmented the expression of AP-1 but attenuated the expression of IRF-4, CDX-2, and Zic-1. Reciprocally, overexpression of miR-1273a abrogated the oncogenic function of circPIP5K1A in colon cancers. CONCLUSION: Overall, our data demonstrate the oncogenic role of circPIP5K1A-miR-1273a axis in regulation of colon cancer development, which provides a novel insights into colon cancer pathogenesis.


Assuntos
Carcinogênese/genética , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Circular/metabolismo , Linhagem Celular Tumoral , Colo/patologia , Neoplasias do Colo/sangue , Biologia Computacional , Progressão da Doença , Técnicas de Silenciamento de Genes , Humanos , Fosfotransferases (Aceptor do Grupo Álcool)/genética , RNA Circular/sangue , RNA Circular/genética , Regulação para Cima
4.
Appl Opt ; 58(22): 6085-6090, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503929

RESUMO

Recently, orbital angular momentum (OAM) beams have been applied in underwater optical communication (UWOC) to build a high-capacity communication link. However, a wave-front-sensitive OAM beam suffers significant distortion due to oceanic turbulence (OT), resulting in considerable intermodal crosstalk that degrades the UWOC performance. Herein, we propose and demonstrate an adaptive optics (AO)-based correction approach with a phase retrieval algorithm (PRA) to compensate for the distorted OAM beams induced by OT. In a simulation, an OT model with the random phase screen method is utilized. Two PRAs, the Gerchberg-Saxton algorithm (GSA) and the hybrid input-output algorithm (HIOA), are utilized to reconstruct the distorted phase-front of the OAM beam. The simulation results illustrate that the PRA-based AO approach can effectively compensate for the distorted OAM beam and improve the bit error rate performance in an oceanic channel. Additionally, the compensation performance of HIOA-based AO is superior to that of GSA-based AO in terms of convergence performance. This work verifies the feasibility and validity of a PRA-based AO approach in underwater turbulence optical communication and provides new insights into the OAM underwater communication system.

5.
Science ; 365(6456): 919-922, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31346137

RESUMO

Rhizobial infection and root nodule formation in legumes require recognition of signal molecules produced by the bacteria and their hosts. Here, we show that rhizobial transfer RNA (tRNA)-derived small RNA fragments (tRFs) are signal molecules that modulate host nodulation. Three families of rhizobial tRFs were confirmed to regulate host genes associated with nodule initiation and development through hijacking the host RNA-interference machinery that involves ARGONAUTE 1. Silencing individual tRFs with the use of short tandem target mimics or by overexpressing their targets represses root hair curling and nodule formation, whereas repressing these targets with artificial microRNAs identical to the respective tRFs or mutating these targets with CRISPR-Cas9 promotes nodulation. Our findings thus uncover a bacterial small RNA-mediated mechanism for prokaryote-eukaryote interaction and may pave the way for enhancing nodulation efficiency in legumes.


Assuntos
Bradyrhizobium/fisiologia , Regulação da Expressão Gênica de Plantas , Interações entre Hospedeiro e Microrganismos/genética , Nodulação/genética , RNA Bacteriano/fisiologia , Pequeno RNA não Traduzido/fisiologia , RNA de Transferência/fisiologia , Soja/microbiologia , Proteínas Argonauta/genética , Bradyrhizobium/genética , Sistemas CRISPR-Cas , Fixação de Nitrogênio , Conformação de Ácido Nucleico , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Interferência de RNA , RNA Bacteriano/química , RNA Bacteriano/genética , Pequeno RNA não Traduzido/química , Pequeno RNA não Traduzido/genética , RNA de Transferência/química , RNA de Transferência/genética , Soja/genética , Soja/metabolismo
6.
Mol Plant ; 12(10): 1366-1382, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31152912

RESUMO

The semi-determinate stem growth habit in leguminous crops, similar to the "green revolution" semi-dwarf trait in cereals, is a key plant architecture trait that affects several other traits determining grain yield. In soybean semi-determinacy is modulated by a post-domestication gain-of-function mutation in the gene, Dt2, which encodes an MADS-box transcription factor. However, its role in systemic modification of stem growth and other traits is unknown. In this study, we show that Dt2 functions not only as a direct repressor of Dt1, which prevents terminal flowering, but also as a direct activator of putative floral integrator/identity genes including GmSOC1, GmAP1, and GmFUL, which likely promote flowering. We also demonstrate that Dt2 functions as a direct repressor of the putative drought-responsive transcription factor gene GmDREB1D, and as a direct activator of GmSPCH and GmGRP7, which are potentially associated with asymmetric division of young epidermal cells and stomatal opening, respectively, and may affect the plant's water-use efficiency (WUE). Intriguingly, Dt2 was found to be a direct activator or repressor of the precursors of eight microRNAs targeting genes potentially associated with meristem maintenance, flowering time, stomatal density, WUE, and/or stress responses. This study thus reveals the molecular basis of pleiotropy associated with plant productivity, adaptability, and environmental resilience.


Assuntos
Domesticação , Mutação , Proteínas de Plantas/genética , Soja/crescimento & desenvolvimento , Soja/genética , Fatores de Transcrição/genética , Flores/crescimento & desenvolvimento , Pleiotropia Genética , Fenótipo , Reguladores de Crescimento de Planta/metabolismo , Transdução de Sinais/genética , Soja/citologia
7.
Appl Opt ; 58(12): 3222-3228, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31044800

RESUMO

A generation scheme for the linear frequency-modulated (LFM) signals with tunable carrier frequency and improved time-bandwidth product (TBWP) using an optical frequency comb (OFC) and a fiber Bragg grating (FBG) time delay line is proposed and demonstrated by simulation. In the scheme, intensity modulation is used to convert the continuous time-domain waveform to an optical pulse with a duty cycle of one-sixteenth, and two cascaded polarization modulators driven by two different radio frequency signals are used to generate 16-line OFC without an optical filter. Then the 16-line OFC is injected into the FBG time delay line, which consists of 16 discrete FBGs, and each spectral line is reflected by the specific FBG after different time delays. By properly designing the position of the FBGs, the 16 spectral lines of the 16-line OFC are separated in the time domain. The time-separated OFC is then modulated by a phase modulator driven by a periodic parabolic signal for introducing parabolic phase modulation. Subsequently, after the heterodyne beating between the phase-modulated optical signal and the local oscillator light wave emitted from a tunable laser source (TLS) in a photodiode, an electrical LFM signal with improved TBWP is generated. Simulation results show that the generated LFM signal has the bandwidth of 31.78 GHz and TBWP of 1365.33, and its center frequency can be tuned by varying the wavelength of the TLS.

8.
Cancer Cell Int ; 19: 36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30820189

RESUMO

Background: Radiation therapy remains an important therapeutic modality, especially for those patients who are not candidates for radical resection. Many strategies have been developed to increase the radiosensitivity of esophageal cancer, with some success. Methods: This study was conducted to determine whether raltitrexed can enhance radiosensitivity of esophageal squamous cell carcinoma (ESCC). ESCC cell lines 24 h were incubated with raltitrexed or DMSO with or without subsequent irradiation. Cell Counting Kit assay-8 assay and clonogenic survival assay were used to measure the cell proliferation and radiosensitization, respectively. Flow cytometry was utilized to examine cell apoptosis and cell cycle distribution in different groups. Immunofluorescence analysis was performed to detect deoxyribonucleic acid (DNA) double-strand breaks. In addition, the expression levels of proteins that are involved in radiation induced signal transduction including Bax, Cyclin B1, Cdc2/pCdc2, and Cdc25C/pCdc25C were examined by western blot analysis. Results: The results indicated that raltitrexed enhanced radiosensitivity of ESCC cells with increased DNA double-strand breaks, the G2/M arrest, and the apoptosis of ESCC cells induced by radiation. The sensitization enhancement ratio of 1.23-2.10 was detected for ESCC cells with raltitrexed treatment in TE-13 cell line. In vitro, raltitrexed also increased the therapeutic effect of radiation in nude mice. Conclusion: Raltitrexed increases the radiosensitivity of ESCC. This antimetabolite drug is promising for future clinical trials with concurrent radiation in esophageal cancer.

9.
Genome Biol ; 20(1): 22, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700312

RESUMO

BACKGROUND: Evidence of introgression, the transfer of genetic material, between crops and their wild relatives through spontaneous hybridization and subsequent backcrossing has been documented; however, the evolutionary patterns and consequences of introgression and its influence on the processes of crop domestication and varietal diversification are poorly understood. RESULTS: We investigate the genomic landscape and evolution of putative crop-wild-relative introgression by analyzing the nuclear and chloroplast genomes from a panel of wild (Glycine soja) and domesticated (Glycine max) soybeans. Our data suggest that naturally occurring introgression between wild and domesticated soybeans was widespread and that introgressed variation in both wild and domesticated soybeans was selected against throughout the genomes and preferentially removed from the genomic regions underlying selective sweeps and domestication quantitative trait locus (QTL). In both taxa, putative introgression was preferentially retained in recombination-repressed pericentromeric regions that exhibit lower gene densities, reflecting potential roles of recombination in purging introgression. Despite extensive removal of introgressed variation by recurrent selection for domestication-related QTL and associated genomic regions, spontaneous interspecific hybridization during soybean domestication appear to have contributed to a rapid varietal diversification with high levels of genetic diversity and asymmetric evolution between the nuclear and chloroplast genomes. CONCLUSIONS: This work reveals the evolutionary forces, patterns, and consequences of putative genomic introgression between crops and their wild relatives, and the effects of introgression on the processes of crop domestication and varietal diversification. We envision that interspecific introgression serves as an important mechanism for counteracting the reduction of genetic diversity in domesticated crops, particularly the ones under single domestication.


Assuntos
Domesticação , Evolução Molecular , Hibridização Genética , Soja/genética , Fluxo Gênico , Genoma de Cloroplastos , Genoma de Planta
10.
Sci Rep ; 9(1): 2432, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30792414

RESUMO

Two influenza B virus lineages, B/Victoria and B/Yamagata, are co-circulating in human population. While the two lineages are serologically distinct and TIV only contain one lineage. It is important to investigate the epidemiological and evolutionary dynamics of two influenza B virus lineages in Beijing after the free influenza vaccine policy from 2007. Here, we collected the nasopharyngeal swabs of 12657 outpatients of influenza-like illness and subtyped by real-time RT-PCR during 2011-2017. The HA and NA genes of influenza B were fully sequenced. The prevalence is the highest in the 6-17 years old group among people infected with influenza B. Yamagata-lineage virus evolved to two inter-clade from 2011-2014 to 2014-2017. The amino acids substitutions of HA1 region were R279K in strains of 2011-2014 and L173Q, M252V in strains of 2014-2017. Substitutions L58P, I146V were observed in HA1 region of Victoria-lineage virus in 2011-2012 and I117V, N129D were showed in 2015-2017. Phylogenetic analysis of NA showed Yamagata-Victoria inter-lineage reassortant occurred in 2013-2014. Influenza B mainly infect the school-aged children in Beijing and the free influenza vaccine inoculation does not seem to block school-age children from infection with influenza B. The antigen characteristics of circulating influenza B were different to the recommended vaccine strains. We concluded that the Victoria-lineage vaccine strain should been changed and the free influenza vaccine should be revalued.

11.
J Am Chem Soc ; 141(9): 3843-3848, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30773007

RESUMO

The first two cage based crystalline covalent organic frameworks, cage-COF-1 and cage-COF-2, were constructed from a prism-like three-aldehyde-containing molecular cage. The cage contains two horizontal phloroglucinol and three vertical triazine moieties forming three identical V-shaped cavities. By reacting with p-phenylenediamine and 4,4'-biphenyldiamine, the two cage-COFs were formed with a hexagonal skeleton and possess a unique structure. Due to the pillared cage nodes, the linkers are hanging with their π-surfaces but not C-H sites exposed to the pore, and enjoy certain rotational dynamics as suggested by 13C CP/MAS NMR. The antidirection of the diimine linkages leads to rippled layers which pack in unique ABC mode through alternate stacking of the cage twosided faces in both AB and AC layers. Such packing forms trigonal channels along c axis which are interconnected in ab plane due to the large open space created across the hanging linkers, resembling the porous characteristics of 3D COFs. The cage-COFs have a permanent porosity and can adsorb CO2 facilitated by the intrinsic cage cavities that serve as prime adsorption sites. The unprecedented cage-COFs not only merge the borderline of 2D and 3D COFs but also bridge porous organic cages to extended crystalline organic frameworks.

12.
Theor Appl Genet ; 132(4): 1195-1209, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30607438

RESUMO

KEY MESSAGE: A total of 132 domestication-related QTLs, of which 41 were novel, were identified through genotyping-by-sequencing of two Glycine max × Glycine soja populations. Soybean [Glycine max (L.) Merr.] was domesticated in East Asia from the wild progenitor Glycine soja. The domestication process led to many distinct morphological changes that adapt it to cultivation. These include larger seeds, erect growth, larger stem diameter, reduced pod shattering, and altered growth habit. The objective of this study was to identify QTLs controlling key domestication-related traits (DRTs) using interspecific mapping populations. A total of 151 RILs from Williams 82 × PI 468916 and 510 RILs from Williams 82 × PI 479752 were utilized for QTL mapping. These lines were genotyped using a genotyping-by-sequencing protocol which resulted in approximately 5000 polymorphic SNP markers. The number of QTLs detected for each of the eleven DRTs ranged between 0-4 QTLs in the smaller Williams 82 × PI 468916 population and 3-16 QTLs in the larger Williams 82 × PI 479752 population. A total of 132 QTLs were detected, of which 51 are associated with selective sweeps previously related to soybean domestication. These QTLs were detected across all 20 chromosomes within 42 genomic regions. This study identifies 41 novel QTLs not detected in previous studies using smaller populations while also confirming the quantitative nature for several of the important DRTs in soybeans. These results would enable more effective use of the wild germplasm for soybean improvement.


Assuntos
Mapeamento Cromossômico , Domesticação , Técnicas de Genotipagem , Característica Quantitativa Herdável , Análise de Sequência de DNA , Soja/genética , Cruzamentos Genéticos , Epistasia Genética , Endogamia , Modelos Genéticos , Fenótipo , Locos de Características Quantitativas/genética , Seleção Genética , Especificidade da Espécie
13.
Genomics ; 111(4): 629-635, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626511

RESUMO

Salt stress causes foliar chlorosis and scorch, plant stunting, and eventually yield reduction in soybean. There are differential responses, namely tolerance (excluder) and intolerance (includer), among soybean germplasm. However, the genetic and physiological mechanisms for salt tolerance is complex and not clear yet. Based on the results from the screening of the RA-452 x Osage mapping population, two F4:6 lines with extreme responses, most tolerant and most sensitive, were selected for a time-course gene expression study in which the 250 mM NaCl treatment was initially imposed at the V1 stage and continued for 24 h (hrs). Total RNA was isolated from the leaves harvested at 0, 6, 12, 24 h after the initiation of salt treatment, respectively. The RNA-Seq analysis was conducted to compare the salt tolerant genotype with salt sensitive genotype at each time point using RNA-Seq pipeline method. A total of 2374, 998, 1746, and 630 differentially expressed genes (DEGs) between salt-tolerant line and salt-sensitive line, were found at 0, 6, 12, and 24 h, respectively. The expression patterns of 154 common DEGs among all the time points were investigated, of which, six common DEGs were upregulated and seven common DEGs were downregulated in salt-tolerant line. Moreover, 13 common DEGs were dramatically expressed at all the time points. Based on Log2 (fold change) of expression level of salt-tolerant line to salt-sensitive line and gene annotation, Glyma.02G228100, Glyma.03G226000, Glyma.03G031000, Glyma.03G031400, Glyma.04G180300, Glyma.04G180400, Glyma.05 g204600, Glyma.08G189600, Glyma.13G042200, and Glyma.17G173200, were considered to be the key potential genes involving in the salt-tolerance mechanism in the soybean salt-tolerant line.


Assuntos
Tolerância ao Sal , Soja/genética , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genótipo , Soja/fisiologia
14.
Appl Opt ; 57(26): 7644-7650, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30461834

RESUMO

Atmospheric turbulence is a major challenge for practical orbital angular momentum (OAM)-based free-space optical (FSO) communication systems that causes intermodal crosstalk and degrades the performance of the system. Herein, we propose a hybrid input-output algorithm (HIOA)-based adaptive optics (AO) system to compensate for distorted OAM beams. The principle and parameters of the HIOA-based AO system in an OAM-based FSO system are analyzed, and the performance is discussed. The simulation results indicate that the HIOA-based AO system can effectively correct distorted OAM beams and that the HIOA improves the compensation performance and convergence speed compared to the traditional Gerchberg-Saxton algorithm. Moreover, we analyze the compensation performance based on different probe beams. Using an OAM beam with state l=1 as a probe beam can yield better correction effects than a Gaussian beam. This work verifies the feasibility of using an HIOA for adaptive turbulence compensation and provides new insights into OAM communication systems.

15.
Front Plant Sci ; 9: 1250, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30271414

RESUMO

Switchgrass (Panicum virgatum) is a native prairie grass and valuable bio-energy crop. The physiological change from juvenile to reproductive adult can draw important resources away from growth into producing reproductive structures, thereby limiting the growth potential of early flowering plants. Delaying the flowering of switchgrass is one approach by which to increase total biomass. The objective of this research was to identify genetic variants and candidate genes for controlling heading and anthesis in segregating switchgrass populations. Four pseudo-F2 populations (two pairs of reciprocal crosses) were developed from lowland (late flowering) and upland (early flowering) ecotypes, and heading and anthesis dates of these populations were collected in Lafayette, IN and DeKalb, IL in 2015 and 2016. Across 2 years, there was a 34- and 73-day difference in heading and a 52- and 75-day difference in anthesis at the Lafayette and DeKalb locations, respectively. A total of 37,901 single nucleotide polymorphisms obtained by exome capture sequencing of the populations were used in a genome-wide association study (GWAS) that identified five significant signals at three loci for heading and two loci for anthesis. Among them, a homolog of FLOWERING LOCUS T on chromosome 5b associated with heading date was identified at the Lafayette location across 2 years. A homolog of ARABIDOPSIS PSEUDO-RESPONSE REGULATOR 5, a light modulator in the circadian clock associated with heading date was detected on chromosome 8a across locations and years. These results demonstrate that genetic variants related to floral development could lend themselves to a long-term goal of developing late flowering varieties of switchgrass with high biomass yield.

16.
Plant J ; 96(4): 761-771, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30112860

RESUMO

Stem growth habit is a key plant architecture trait determining yield potential in grain legumes, and the phenotypic change from the indeterminate stem growth habit of wild mungbeans (Vigna radiata) to the determinate stem growth habit of cultivated mungbeans is a critical domestication transition. Here we show that indeterminate stem growth in wild mungbean is modulated by a single gene, VrDet1, which encodes a signaling protein of shoot apical meristems. The transition from an indeterminate to a determinate stem growth habit was achieved by selection of two linked point mutations in two putative cis-regulatory elements, resulting in a significant reduction in gene expression. Both the wild-type nucleotides corresponding to the two point mutations were essential for VrDet1 function. In addition, two highly diverse haplotypes of Vrdet1 were found in cultivated mungbeans, suggesting dual domestication of Vrdet1. VrDet1 was orthologous to Dt1 in wild soybean and PvTFL1y in wild common bean, where multiple loss-of-function mutations altering the coding sequences of individual genes were selected to produce determinate stems in cultivated accessions. Interspecific comparison of these orthologs in the wild and cultivated accessions reveals the most conservative interspecific and intraspecific parallel domestication events with the broadest mutational spectrum of a domestication trait in leguminous crops. We also found that interspecifically and functionally conserved promoters possess cis-regulatory elements that are highly conserved in kind but greatly variable in number and order, demonstrating the evolutionary dynamics of regulatory sequences. This work provides insights into the origins of cultivated mungbean and exemplifies the conservativeness and plasticity of the domestication processes of related crops.


Assuntos
Produtos Agrícolas/genética , Domesticação , Fabaceae/genética , Mutação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Fabaceae/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Haplótipos , Meristema/genética , Meristema/crescimento & desenvolvimento , Fenótipo , Análise de Sequência de DNA , Vigna/genética , Vigna/crescimento & desenvolvimento
17.
Nat Plants ; 4(1): 30-35, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29292374

RESUMO

Many leguminous species have adapted their seed coat with a layer of powdery bloom that contains hazardous allergens and makes the seeds less visible, offering duel protection against potential predators 1 . Nevertheless, a shiny seed surface without bloom is desirable for human consumption and health, and is targeted for selection under domestication. Here we show that seed coat bloom in wild soybeans is mainly controlled by Bloom1 (B1), which encodes a transmembrane transporter-like protein for biosynthesis of the bloom in pod endocarp. The transition from the 'bloom' to 'no-bloom' phenotypes is associated with artificial selection of a nucleotide mutation that naturally occurred in the coding region of B1 during soybean domestication. Interestingly, this mutation not only 'shined' the seed surface, but also elevated seed oil content in domesticated soybeans. Such an elevation of oil content in seeds appears to be achieved through b1-modulated upregulation of oil biosynthesis in pods. This study shows pleiotropy as a mechanism underlying the domestication syndrome 2 , and may pave new strategies for development of soybean varieties with increased seed oil content and reduced seed dust.


Assuntos
Pleiotropia Genética/genética , Óleo de Soja/metabolismo , Soja/genética , Domesticação , Fenótipo , Sementes/anatomia & histologia , Sementes/genética , Soja/anatomia & histologia
18.
Pathol Oncol Res ; 24(1): 75-81, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28341911

RESUMO

Murine double minute 2 (MDM2) negatively regulates the activity of the p53 protein and plays a vital role in cell cycle arrest, apoptosis, and senescence mediated by p53. Nutlin-3, an antagonist of MDM2, is frequently used in anti-cancer studies. In many human tumors, nutlin-3 stabilizes p53 status and enhances p53 expression in cells with wild-type p53. However, the effect of nutlin-3 combined with radiotherapy on esophageal squamous cancer (ESCC) has not been reported. In this study, we examined whether nutlin-3 increases the radiosensitivity of ESCC in vitro and in vivo.We chose two cell lines, ECA-109 (wild-type p53) and TE-13 (p53 mutated), for the following experiments. Cell proliferation and clonogenic survival experiments showed that nutlin-3 inhibits the cell growth and colony formation of ECA-109 cells in a dose-dependent manner. Flow cytometry analysis showed that the apoptosis rate of ECA-109 cells co-treated with nutlin-3 and irradiation(IR) was significantly increased compared with cells treated with irradiation or nutlin-3 alone. Western blotting detected the expression of apoptosis-associated proteins in ECA-109 cells in response to nutlin-3 and irradiation. These effects were not evident in TE-13 cells. Xenograft mouse models indicated that nutlin-3 suppresses tumor growth and promotes radiosensitivity in the ESCC cell line ECA-109 in vivo. We have demonstrated that co-treatment of nutlin-3 with irradiation can significantly inhibit the growth and improve the radiosensitivity of ESCC cells with wild-type p53. The study suggests that nutlin-3 may be a potent therapeutic agent in conjunction with radiotherapy in ESCC.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Esofágicas/radioterapia , Imidazóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Tolerância a Radiação/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Raios gama , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Plant Cell ; 29(12): 2974-2994, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29180596

RESUMO

Polyploidy is an important feature of plant genomes, but the nature of many polyploidization events remains to be elucidated. Here, we demonstrate that the evolutionary fates of the subgenomes in maize (Zea mays) and soybean (Glycine max) have followed different trajectories. One subgenome has been subject to relaxed selection, lower levels of gene expression, higher rates of transposable element accumulation, more small interfering RNAs and DNA methylation around genes, and higher rates of gene loss in maize, whereas none of these features were observed in soybean. Nevertheless, individual gene pairs exhibit differentiation with respect to these features in both species. In addition, we observed a higher number of chromosomal rearrangements and higher frequency of retention of duplicated genes in soybean than in maize. Furthermore, soybean "singletons" were found to be more frequently tandemly duplicated than "duplicates" in soybean, which may, to some extent, counteract the genome imbalance caused by gene loss. We propose that unlike in maize, in which two subgenomes were distinct prior to the allotetraploidization event and thus experienced global differences in selective constraints, in soybean, the two subgenomes were far less distinct prior to polyploidization, such that individual gene pairs, rather than subgenomes, experienced stochastic differences over longer periods of time, resulting in retention of the majority of duplicates.


Assuntos
Genoma de Planta , Paleontologia , Plantas/genética , Poliploidia , Soja/genética , Zea mays/genética , Centrômero/genética , Cromossomos de Plantas/genética , Metilação de DNA/genética , Elementos de DNA Transponíveis/genética , Epigênese Genética , Evolução Molecular , Duplicação Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genes Duplicados , Genes de Plantas , Phaseolus/genética , RNA Interferente Pequeno/metabolismo , Retroelementos/genética , Seleção Genética , Especificidade da Espécie , Sintenia/genética
20.
Cent Eur J Immunol ; 42(1): 97-100, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28680337

RESUMO

Developed chronic hepatitis B (CHB) causes death in approximately one million patients every year. Therefore, natural drugs with high therapeutic efficacy and minimal side effects must be developed for CHB treatment. This study aimed to relate the therapeutic effects of glutathione on CHB. A total of 104 CHB patients were randomly divided into two groups: the control group, which received an intravenous drip of 0.4 g of inosine injection with 250 ml of 5% glucose once a day for eight weeks, and the treatment group, which received an intravenous drip of 1200 mg of glutathione on the basis of the treatment of the control group. Glutathione treatment decreased the serum levels of asparaginic acid transaminase, alanine aminotransferase, total bilirubin, total bile acids, haluronic acid, collagen IV, laminin, transforming growth factor-ß1, tumour necrosis factor-α, interleukin-6, and interleukin-8, compared with the control group. The results indicate that glutathione treatment can improve liver function and inhibit inflammation and hepatic fibrosis in CHB patients.

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