RESUMEN
Soybean (Glycine max) is a typical short-day plant, but has been widely cultivated in high-latitude long-day (LD) regions because of the development of early-maturing genotypes which are photoperiod-insensitive. However, some early-maturing varieties exhibit significant responses to maturity under different daylengths but not for flowering, depicting an evident photoperiodic after-effect, a poorly understood mechanism. In this study, we investigated the postflowering responses of 11 early-maturing soybean varieties to various preflowering photoperiodic treatments. We confirmed that preflowering SD conditions greatly promoted maturity and other postflowering developmental stages. Soybean homologs of FLOWERING LOCUS T (FT), including GmFT2a, GmFT3a, GmFT3b and GmFT5a, were highly accumulated in leaves under preflowering SD treatment. More importantly, they maintained a high expression level after flowering even under LD conditions. E1 RNAi and GmFT2a overexpression lines showed extremely early maturity regardless of preflowering SD and LD treatments due to constitutively high levels of floral-promoting GmFT homolog expression throughout their life cycle. Collectively, our data indicate that high and stable expression of floral-promoting GmFT homologs play key roles in the maintenance of photoperiodic induction to promote postflowering reproductive development, which confers early-maturing varieties with appropriate vegetative growth and shortened reproductive growth periods for adaptation to high latitudes.
Asunto(s)
Glycine max , Fotoperiodo , Glycine max/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/fisiología , Ritmo Circadiano , Regulación de la Expresión Génica de las PlantasRESUMEN
SOS2-like protein kinases (PKS/CIPK) family genes are known to be involved in various abiotic stresses in plants. Even though, its functions have been well characterized under salt and drought stresses. The roles of PKS genes associated with alkaline stress response are not fully established yet. In this study, we identified 56 PKS family genes which could be mainly classified into three groups in wild soybean (Glycine soja). PKS family genes transcript profiles revealed different expression patterns under alkali stress. Furthermore, we confirmed the regulatory roles of GsPKS24 in response to NaHCO3, pH and ABA treatments. Overexpression of GsPKS24 enhanced plant tolerance to pH stress in Arabidopsis and soybean hairy roots but conferred suppressed pH tolerance in Arabidopsis atpks mutant. Additionally, Overexpression of GsPKS24 decreased the ABA sensitivity compared to Arabidopsis atpks mutant which displayed more sensitivity towards ABA. Moreover, upregulated expression of stress responsive and ABA signal-related genes were detected in GsPKS24 overexpression lines. In conclusion, we identified the wild soybean PKS family genes, and explored the roles of GsPKS24 in positive response to pH stress tolerance, and in alleviation of ABA sensitivity.
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Arabidopsis , Fabaceae , Arabidopsis/genética , Calcineurina , Transducción de Señal , Glicina , Concentración de Iones de HidrógenoRESUMEN
Strigolactone (SL) is a new plant hormone, which not only plays an important role in stimulating seed germination, plant branching, and regulating root development, but also plays an important role in the response of plants to abiotic stresses. In this study, the full-length cDNA of a soybean SL signal transduction gene (GmMAX2a) was isolated, cloned and revealed an important role in abiotic stress responses. Tissue-specific expression analysis by qRT-PCR indicated that GmMAX2a was expressed in all tissues of soybean, but highest expression was detected in seedling stems. Moreover, upregulation of GmMAX2a transcript expression under salt, alkali, and drought conditions were noted at different time points in soybean leaves compared to roots. Additionally, histochemical GUS staining studies revealed the deep staining in PGmMAX2a: GUS transgenic lines compared to WT indicating active involvement of GmMAX2a promoter region to stress responses. To further investigate the function of GmMAX2a gene in transgenic Arabidopsis, Petri-plate experiments were performed and GmMAX2a OX lines appeared with longer roots and improved fresh biomass compared to WT plants to NaCl, NaHCO3, and mannitol supplementation. Furthermore, the expression of several stress-related genes such as RD29B, SOS1, NXH1, AtRD22, KIN1, COR15A, RD29A, COR47, H+-APase, NADP-ME, NCED3, and P5CS were significantly high in GmMAX2a OX plants after stress treatment compared to WT plants. In conclusion, GmMAX2a improves soybean tolerance towards abiotic stresses (salt, alkali, and drought). Hence, GmMAX2a can be considered a candidate gene for transgenic breeding against various abiotic stresses in plants.
Asunto(s)
Arabidopsis , Cloruro de Sodio , Glycine max/genética , Arabidopsis/genética , Sequías , Fitomejoramiento , ÁlcalisRESUMEN
KEY MESSAGE: IBD analysis clarified the dynamics of chromosomal recombination during the ZP pedigree breeding process and identified ten genomic regions resistant to SCN race3 combining association mapping. Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is one of the most devastating pathogens for soybean production worldwide. The cultivar Zhongpin03-5373 (ZP), derived from SCN-resistant progenitor parents, Peking, PI 437654 and Huipizhi Heidou, is an elite line with high resistance to SCN race3. In the current study, a pedigree variation map was generated for ZP and its ten progenitors using 3,025,264 high-quality SNPs identified from an average of 16.2 × re-sequencing for each genome. Through identity by decent (IBD) tracking, we showed the dynamic change of genome and detected important IBD fragments, which revealed the comprehensively artificial selection of important traits during ZP breeding process. A total of 2,353 IBD fragments related to SCN resistance including SCN-resistant genes rhg1, rhg4 and NSFRAN07 were identified based on the resistant-related genetic paths. Moreover, 23 genomic regions underlying resistance to SCN race3 were identified by genome-wide association study (GWAS) in 481 re-sequenced cultivated soybeans. Ten common loci were found by both IBD tracking and GWAS analysis. Haplotype analysis of 16 potential candidate genes suggested a causative SNP (C/T, - 1065) located in the promoter of Glyma.08G096500 and encoding a predicted TIFY5b-related protein on chr8 was highly correlated with SCN race3 resistance. Our results more thoroughly elucidated the dynamics of genomic fragments during ZP pedigree breeding and the genetic basis of SCN resistance, which will provide useful information for gene cloning and the development of resistant soybean cultivars using a marker-assisted selection approach.
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Glycine max , Tylenchoidea , Animales , Glycine max/genética , Glycine max/metabolismo , Estudio de Asociación del Genoma Completo/métodos , Fitomejoramiento , Genes de Plantas , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genéticaRESUMEN
To characterize IncI1 and IncF18:A-:B1 multidrug-resistance plasmids from an avian Escherichia coli isolate, antibiotic susceptibility testing, conjugation assays, transformation assays, S1-PFGE, and WGS analysis were performed. The 119,457-bp plasmid pEC014-1 with a multidrug-resistance region (MRR) containing four different segments interspersed with six IS26 elements, belonged to incompatibility group I1 and sequence type 71. The 154,516-bp plasmid pEC014-2 with two replicons, typed as FII-18 and FIB-1, carried 14 resistance determinants including blaTEM-1b, blaOXA-1, oqxAB, dfrA17, aac(6')-Ib-cr, sul1, sul2, tet(A), floR, catB3, hph(aph(4)-Ia), aacC4(aac(3)-IV), aadA5, arr-3, and a merEDACPTR loci in MRR, and additionally encoded three virulence loci: iroNEDCB, sitABCD, and iucABCD-iutA. Plasmid stability assays showed that pEC014-1 and pEC014-2 were stable in recipient E. coli C600 for at least 15 days of passage. Competition assays were carried out to evaluate the fitness impact of pEC014-2 carriage in vitro, revealing a decrease in host fitness. Growth kinetics showed that the growth rate for pEC014-1 or/and pEC014-2 bearing cells was significantly slower than that of the E. coli C600 host strain in the exponential stage (p < 0.01), with only cells carrying pEC014-1 sustaining rapid growth after 6 h of exponential growth. Our findings highlight the mosaic structures of epidemic plasmid IncI1/ST71 and F18:A-:B1 lineages and contribute to a better understanding of the evolution and dissemination of these multidrug resistance and virulence plasmids.
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Infecciones por Escherichia coli , Escherichia coli , Humanos , Plásmidos/genética , beta-Lactamasas/genética , Pruebas de Sensibilidad Microbiana , Infecciones por Escherichia coli/epidemiología , Resistencia a Múltiples Medicamentos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genéticaRESUMEN
The plant hormone strigolactones (SLs) play crucial roles in regulating plant development and adaptations to abiotic stresses. Even though the functional roles of SLs have been identified in response to abiotic stresses, the function, and mechanism of SLs are not fully established under alkaline stress. In this study, we identified that exogenous SL could improve alkaline tolerance of soybean seedlings, especially when treated with 0.5 µM SL. The application of SL remarkably reduced the malondialdehyde content, hydrogen peroxide content, and increased the activity of antioxidant enzymes under alkaline stress, suggesting that SL improved the alkaline tolerance by regulating the antioxidant defense capacity. The RNA sequencing data showed 530 special differentially expressed genes under SL treatment and alkaline stress, mainly were associated with antioxidant processes and phenylpropanoid biosynthetic pathway. Some transcription factors were also induced by SL under alkaline stress as confirmed by quantitative real-time PCR (qRT-PCR). Furthermore, SL largely increased the Na content in leaves and decreased Na content in roots under alkaline stress, which suggested that SL might promote the transport of Na from the roots to the leaves of the soybean seedlings. Meanwhile, exogenous SL decreased the content of other elements such as K, Mg, Fe, and Cu in leaves or roots under alkaline stress. Collectively, our results suggested a role of SL in regulating antioxidant defense capacity, specific gene expression, and alterations in ionic contents to alleviate harmful effects of alkaline stress in soybean seedlings.
Asunto(s)
Glycine max , Plantones , Plantones/metabolismo , Glycine max/fisiología , Reguladores del Crecimiento de las Plantas/metabolismo , Peróxido de Hidrógeno/metabolismo , Antioxidantes , Malondialdehído , Factores de TranscripciónRESUMEN
MicroRNAs (miRNAs) play key roles in cervical cancer metastasis progression. Accumulated evidences have revealed that miRNAs are related to the pathophysiological process. However, the role of miR-340 in cervical cancer and how it works is still not fully interpreted. Using qRT-PCR to examine the expression of miR-340 in cervical cancer tissues. Transwell migration and invasion experiments were used to detect the role of miR-340 in migration and invasion. Luciferase reporter assay, qRT-PCR, and Western blot were used to detect the relationship between miR-340 and EphA3. Using Transwell migration and invasion experiments to investigate the role of EphA3 on migration and invasion. Restoration expriments were also performed. Western blot was used to assay the influence of miR-340 and EphA3 on EMT. We found that miR-340 was downregulated in cervical cancer tissues compared with the normal tissues. Transwell migration and invasion experiments indicated that overexpression of miR-340 frequently inhibited the migration and invasion of cervical cancer cells. EphA3 is a target of miR-340, and ectopic expression of EphA3 can promote the migration and invasion of cervical cancer cells, whereas restoration of EphA3 in miR-340-overexpressing cervical cancer cells reversed the suppressive effects of miR-340. What's more, the process of migration and invasion which regulated by miR-340/EphA3 was depended on adjusting the EMT way. These findings indicate that miR-340 may act as an anti-tumor factor during the process of tumor metastasis through targeting EphA3, suggesting that miR-340 might be a potential new diagnostic and therapeutic molecule for the treatment of cervical cancer.
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MicroARNs/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Adulto , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Transición Epitelial-Mesenquimal , Femenino , Células HeLa , Humanos , MicroARNs/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Proteínas Tirosina Quinasas Receptoras/genética , Receptor EphA3 , Transcriptoma , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patologíaRESUMEN
The morphology and infraciliature of one freshwater ciliate, Cyclidium sinicum spec. nov., isolated from a farmland pond in Harbin, northeastern China, was investigated using living observation and silver staining methods. Cyclidium sinicum spec. nov. could be distinguished by the following features: body approximately 20-25×10-15 µm in vivo; buccal field about 45-50â% of body length; 11 somatic kineties; somatic kinety n terminating sub-caudally; two macronuclei and one micronucleus; M1 almost as long as M2; M2 triangle-shaped. The genus Cyclidium is re-defined as follows: body outline usually oval or elliptical, ventral side concave, dorsal side convex; single caudal cilium; contractile vacuole posterior terminal; adoral membranelles usually not separated; paroral membrane 'L'-shaped, with anterior end terminating at the level of anterior end of M1; somatic kineties longitudinally arranged and continuous. Phylogenetic trees based on the SSU rDNA sequences showed that C. sinicum spec. nov. clusters with the type species, Cyclidiumglaucoma, with full support. Cyclidium is not monophyletic with members of the clade of Cyclidium+Protocyclidium+Ancistrum+Boveria.
Asunto(s)
Agua Dulce/microbiología , Oligohimenóforos/clasificación , Filogenia , China , ADN Ribosómico/genética , Oligohimenóforos/genética , Oligohimenóforos/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
OBJECTIVE: To analyze the present situation and influencing factors of discrimination against hepatitis B patients and carriers among rural adults in three eastern provinces in China. METHODS: By using the method of probability proportionate to size (PPS), we involved a sample of 9 269 rural adults aged above 18 years old from 22 villages of 7 counties in Beijing, Hebei, Shandong in 2011 and 2012. We used a self-designed interview questionnaire with questions about the individual and household characteristics, attitudes toward hepatitis B patients and carriers, individual HBV vaccination history, etc. We analyzed the hepatitis B discrimination score and its distribution, and we also created a multinomial logistic regression model to analyze the influencing factors of discrimination. RESULTS: Of all the participants, 51.15% (4 741) were afraid of being infected with HBV when getting on with hepatitis B patients or carriers; 51.29% (4 754), 61.14% (5 667) and 52.22% (4 841) of them were not willing to accept gifts from hepatitis B patients or carriers, have dinner with them, or hug and shake hands with them, respectively; 73.92% (6 852) were unwilling to their children's playing with kids whose parents were hepatitis B patients or carriers, and 86.68% (8 034) were unwilling to their children's marrying hepatitis B patients or carriers. Of all the participants, only 0.88% (82) were totally discrimination-free (discrimination score = 0); mild or without discrimination (< 0 discrimination score ≤ 5) accounted for 23.70% (2 197/9 269); severe discrimination (discrimination score ≥ 6) accounted for 76.30% (7 072). The multiple multinomial logistic regression showed that migratory workers, other occupations like technician, civil servants and village doctors were less likely to show severe HBV-related discrimination compared with farmers, with OR (95% CI) 0.86 (0.75-0.98), 0.77 (0.67-0.87), 0.57 (0.41-0.79), respectively. Compared with the lowest income group (< 10 000 RMB/year per person), and the highest income group (> 40 000 RMB/year per person) had an OR (95% CI) of 0.57 (0.46-0.70). People with higher education tended to show less severe discrimination. The high education group had an OR (95% CI) of 0.64 (0.51-0.80) based on the low education group. And compared with people whose self-assessment of health status was very good, those who assessed their health status as very poor showed less severe discrimination, with an OR (95% CI) of 0.41 (0.25-0.67). CONCLUSION: The situation of discrimination against hepatitis B patients and carriers among rural adults in three eastern provinces was serious. It is of great urgency to eliminate the discrimination. Work on eliminating hepatitis B discrimination should focus on farmers, people with low incomes, and people with low educational level.
Asunto(s)
Portador Sano , Conocimientos, Actitudes y Práctica en Salud , Hepatitis B/psicología , Población Rural , Discriminación Social , Adulto , Beijing , Composición Familiar , Humanos , Modelos Logísticos , Ocupaciones , Encuestas y CuestionariosRESUMEN
The Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1) is a convergent node for oncogenic cell-signaling cascades. Consequently, SHP1 represents a potential target for drug development in cancer treatment. The development of efficient methods for rapidly tracing and modulating the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of the related disease. Thus, we designed and synthesized a series of imidazo[1,2,4] triazole derivatives containing salicylic acid to explore novel scaffolds with inhibitory activities and good fluorescence properties for SHP1. The photophysical properties and inhibitory activities of these imidazo[1,2,4] triazole derivatives (5a-5y) against SHP1PTP were thoroughly studied from the theoretical simulation and experimental application aspects. The representative compound 5p exhibited remarkable fluorescence response (P: 0.002) with fluorescence quantum yield (QY) of 0.37 and inhibitory rate of 85.21 ± 5.17% against SHP1PTP at the concentration of 100 µM. Furthermore, compound 5p showed obvious aggregation caused quenching (ACQ) effect and had high selectivity for Fe3+ ions, good anti-interference and relatively low detection limit (5.55 µM). Finally, the cellular imaging test of compound 5p also exhibited good biocompatibility and certain potential biological imaging application. This study provides a potential way to develop molecules with fluorescent properties and bioactivities for SHP1.
Asunto(s)
Proteínas Tirosina Fosfatasas , Transducción de Señal , Fluorescencia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Triazoles/farmacologíaRESUMEN
The station-level ridership during the peak hour is one of the key indicators for the design of station size and relevant facilities. However, with the operation of metro system, it cannot be ignored that, in many cities, the station peak and the city peak may not be simultaneously occurred. As the current ridership forecasting methods use the city peak as the point of reference, stations with wide differences of ridership in between would experience disorders due to serious underestimates of passenger demand during the actual peak. Accordingly, this study fully considers the phenomenon that the metro station peak is not identical to the city peak and focuses on the concept of the peak deviation coefficient (PDC), the ratio of the station peak ridership to the city peak ridership. It investigates how metro ridership determinants affects the PDC using the least square support vector machine (LSSVM) model. A land-use function complementarity index is employed as one of the independent variables, which is newly proposed in this study that describes the relationship of the commute land use around an individual station with that along the whole network. This method can help to resolve the ridership amplification indicator for a fine-grained station-level forecasting. The results for Xi'an metro indicate that the LSSVM is an effective method to scrutinize the nonlinear effects of e.g., land use attributes, on the temporal distribution features of the metro ridership. Compared to the ratio of commute land use measured for individual stations, the land-use function complementarity index can better explain and predict the severity of peak deviation phenomenon, controlling other independent variables in the model.
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Máquina de Vectores de Soporte , Análisis de los Mínimos Cuadrados , CiudadesRESUMEN
Oil-in-water nanoemulsions were produced in the system water/Span 80-Tween 80/paraffin oil via the phase inversion composition (PIC) method at elevated temperature. With the increase of preparation temperature from 20 to 70 °C, we found that the emulsion droplet diameter decreases from 10.3 µm to 51 nm, proving the formation of nanoemulsions. The viscosity of nanoemulsions clearly increases with droplet volume fraction, φ, but the droplet size changes less. Significantly, at φ ≤ 0.5, the size distribution of nanoemulsions can be kept unchangeable more than 5 months. These results proved that the highly viscous paraffin oil can hardly be dispersed by the PIC method at 25 °C, but the increase in preparation temperature makes it possible for producing monodisperse nanoemulsions. Once the nanoemulsion is produced, the stability against Ostwald ripening is outstanding due to the extremely low solubility of the paraffin oil in the continuous phase. The highly stable nanoemulsions are of great importance in practical applications.
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Nanoestructuras/química , Temperatura , Emulsiones/química , Hexosas/química , Aceites/química , Parafina/química , Tamaño de la Partícula , Polisorbatos/química , Propiedades de Superficie , Viscosidad , Agua/químicaRESUMEN
Seed-coat color has changed from black to yellow during natural and artificial selection of cultivated soybean from wild soybean, and it is also an important morphological marker. Therefore, discovering genes related to the soybean seed-coat color will play a very important role in breeding and evolutionary study. Different seed-coat colors caused by deposition of various anthocyanin pigments. Although pigmentation has been well dissected at molecular level in several plant species, the genes controlling natural variation of seed-coat color in soybean remain to be unknown. Genes related to seed-coat color in soybean were discussed in this paper, including 5 genetic loci (I, T, W1, R and O). Locus I is located in a region that riches in chalcone synthase (CHS) genes on chromosome 8. Gene CHS is a multi-gene family with highly conserved sequences in soybean. Locus T located on chromosome 6 has been cloned and verified, which encodes a flavon-oid-3'-hydroxylase. Mutant of F3'H can not interact with the heme-binding domain due to lack of conservative domain GGEK caused by a nucleotide deletion in the coding region of F3'H. Locus R is located between A668-1 and K387-1 on chromosome 9 (linkage group K). This locus may encode a R2R3 MYB transcription factor or a UDP flavonoid 3-O glyco-syltransferase. Locus O is located between Satt207 and Satt493 on chromosome 8 (linkage group A2) and its molecular characteristics has not been characterized. Locus W1 may be a homology of F3'5'H gene.
Asunto(s)
Evolución Molecular , Genes de Plantas , Glycine max/genética , Pigmentación/genética , Semillas/genética , ColorRESUMEN
Background: NDR1/HIN1-like (NHL) family genes are known to be involved in pathogen induced plant responses to biotic stress. Even though the NHL family genes have been identified and characterized in plant defense responses in some plants, the roles of these genes associated with the plant abiotic stress tolerance in wild soybean is not fully established yet, especially in response to alkaline stress. Methods: We identified the potential NHL family genes by using the Hidden Markov model and wild soybean genome. The maximum-likelihood phylogenetic tree and conserved motifs were generated by using the MEME online server and MEGA 7.0 software, respectively. Furthermore, the syntenic analysis was generated with Circos-0.69. Then we used the PlantCARE online software to predict and analyze the regulatory cis-acting elements in promoter regions. Hierarchical clustering trees was generated using TM4: MeV4.9 software. Additionally, the expression levels of NHL family genes under alkaline stress, ABA and MEJA treatment were identified by qRT-PCR. Results: In this study, we identified 59 potential NHL family genes in wild soybean. We identified that wild soybean NHL family genes could be mainly classified into five groups as well as exist with conserved motifs. Syntenic analysis of NHL family genes revealed genes location on 18 chromosomes and presence of 65 pairs of duplication genes. Moreover, NHL family genes consisted of a variety of putative hormone-related and abiotic stress responsive elements, where numbers of methyl jasmonate (MeJA) and abscisic acid (ABA) responsive elements were significantly larger than other elements. We confirmed the regulatory roles of NHL family genes in response to alkaline stress, ABA and MEJA treatment. In conclusion, we identified and provided valuable information on the wild soybean NHL family genes, and established a foundation to further explore the potential roles of NHL family genes in crosstalk with MeJA or ABA signal transduction mechanisms under alkaline stress.
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Ácido Abscísico , Fabaceae , Ácido Abscísico/metabolismo , Glycine max/genética , Filogenia , Fabaceae/genética , Glicina/genéticaRESUMEN
Cadmium (Cd), as a heavy metal, not only negatively affects the development and yield of plants, but also threatens human health due to its accumulation in plants. Increasing evidences indicate that the JUMONJI-C DOMAIN-CONTAINING PROTEIN (JMJ) gene family plays a key role in regulating plant development and stress. Therefore, in this study, SlJMJ524, a 1254 bp gene encoding the jumonji C domain (417 amino acids), was highly expressed in tomato leaves and flowers. Interestingly, the transgenic plants exhibited sensitivity to Cd during post-germination stage but showed enhanced tolerance to the heavy metal during adult stage. Overexpression of SlJMJ524 increased the expression level of related proteins gene involved in heavy metal uptake while increasing Cd tolerance through the GSH-PC pathway. The higher transcription of genes related to flavonoid synthesis reflected higher accumulations of flavonoids in transgenic plants. Our study demonstrated that the ectopic expression of SlJMJ524 conferred the transgenic plants many traits for improving cadmium stress tolerance at different developmental stages. This study advances our collective understanding of the functional role of JMJs and can be used to improve the cadmium tolerance and breeding of crops and plants.
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Arabidopsis , Solanum lycopersicum , Arabidopsis/genética , Arabidopsis/metabolismo , Cadmio/metabolismo , Cadmio/toxicidad , Flavonoides/genética , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , FitomejoramientoRESUMEN
Onset of flowering of plants is precisely controlled by extensive environmental factors and internal molecular networks, in which FLOWERING LOCUS T (FT) is a key flowering integrator. In soybean, a typical short-day plant, 11 FT homologues are found in its genome, of which several homologues are functionally diversified in flowering pathways and the others including GmFT3a are yet unknown. In the current study, we characterized GmFT3a, which is located on the same chromosome as the flowering promoters GmFT2a and GmFT5a. Overexpression of GmFT3a significantly promoted flowering of Arabidopsis under the inductive long-day (LD) photoperiod. GmFT3a over-expressed soybean also flowered earlier than the control under LD, but they were not significantly different under inductive short-day (SD) conditions, indicating that GmFT3a acts as a flowering promoter in the non-inductive photoperiod in soybean. Compared with other GmFT homologues, GmFT3a exhibited a slighter effect in flowering promotion than GmFT2a, GmFT5a and GmFT2b under LD conditions. GmFT3a promoted flowering by regulating the expression of downstream flowering-related genes and also affected the expression of other GmFTs. According to the re-sequencing data, the regional distributions of two major haplotypes in 176 soybean varieties were analyzed. The varieties with GmFT3a-Hap2 haplotype matured relatively early, and relative higher expression of GmFT3a was detected in early maturing varieties, implying that Hap2 variation may contribute to the adaptation of soybean to higher latitude regions by increasing expression level of genes in metabolism and signaling pathways. The early flowering germplasm generated by overexpression of GmFT3a has potential to be planted at higher latitudes where non-inductive long day is dominant in the growing season, and GmFT3a can be used to fine-tune soybean flowering and maturity time and improve the geographical adaptation.
RESUMEN
The aims of this study were to elucidate the role of IS1294 in plasmid reorganization and to analyze biological characteristics of cointegrates derived from different daughter plasmids. The genetic profiles of plasmids in Escherichia coli strain C21 and its transconjugants were characterized by conjugation, S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern hybridization, whole-genome sequencing (WGS) analysis, and PCR. The traits of cointegrates were characterized by conjugation and stability assays. blaCTX-M-55-bearing IncI2 pC21-1 and nonresistant IncI1 pC21-3, as conjugative helper plasmids, were fused with nonconjugative rmtB-bearing IncN-X1 pC21-2, generating cointegrates pC21-F1 and pC21-F2. Similarly, pC21-1 and pC21-3 were fused with nonconjugative IncF33:A-:B- pHB37-2 from another E. coli strain to generate cointegrates pC21-F3 and pC21-F4 under experimental conditions. Four cointegrates were further conjugated into the E. coli strain J53 recipient at high conjugation frequencies, ranging from 2.8 × 10-3 to 3.2 × 10-2. The formation of pC21-F1 and pC21-F4 was the result of host- and IS1294-mediated reactions and occurred at high fusion frequencies of 9.9 × 10-4 and 2.1 × 10-4, respectively. Knockout of RecA resulted in a 100-fold decrease in the frequency of plasmid reorganization. The phenomenon of cointegrate pC21-F2 and its daughter plasmids coexisting in transconjugants was detected for the first time in plasmid stability experiments. IS26-orf-oqxAB was excised from cointegrate pC21-F2 through a circular intermediate at a very low frequency, which was experimentally observed. To the best of our knowledge, this is the first report of IS1294-mediated fusion between plasmids with different replicons. This study provides insight into the formation and evolution of cointegrate plasmids under different drug selection pressures, which can promote the dissemination of MDR plasmids. IMPORTANCE The increasing resistance to ß-lactams and aminoglycoside antibiotics, mainly due to extended-spectrum ß-lactamases (ESBLs) and 16S rRNA methylase genes, is becoming a serious problem in Gram-negative bacteria. Plasmids, as the vehicles for resistance gene capture and horizontal gene transfer, serve a key role in terms of antibiotic resistance emergence and transmission. IS26, present in many antibiotic-resistant plasmids from Gram-negative bacteria, plays a critical role in the spread, clustering, and reorganization of resistance determinant-encoding plasmids and in plasmid reorganization through replicative transposition mechanisms and homologous recombination. However, the role of IS1294, present in many MDR plasmids, in the formation of cointegrates remains unclear. Here, we investigated experimentally the intermolecular recombination of IS1294, which occurred with high frequencies and led to the formation of conjugative MDR cointegrates and facilitated the cotransfer of blaCTX-M-55 and rmtB, and we further uncovered the significance of IS1294 in the formation of cointegrates and the common features of IS1294-driven cointegration of plasmids.
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Antibacterianos/farmacología , Elementos Transponibles de ADN , Escherichia coli/genética , Plásmidos/genética , Conjugación Genética , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Plásmidos/metabolismoRESUMEN
Contamination of soils with cadmium (Cd) is a serious problem worldwide. Solanum nigrum L. is reported as a Cd hyperaccumulator, but its enrichment capacity is limited. 2,4-Epibrassinolide (2,4-EBL) plays important roles in plant response to various stresses. Little is known about its effect on Cd tolerance in S. nigrum. Current study was performed to demonstrate effects of 2,4-EBL on plant growth, photosynthesis activity, activities of antioxidants, and Cd concentration in plants by nutrient solution contaminated with Cd. Results revealed that S. nigrum exhibited toxicity to Cd stress, including reducing plant height, root length, and chlorophyll content and increasing malondialdehyde (MDA) content. Exogenous application of 2,4-EBL significantly enhanced the contents of proline and soluble sugar and decreased the MDA content. Meanwhile, the levels of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) markedly increased compared with the control. Interesting, 2,4-EBL promoted photosynthesis by increasing the chlorophyll content, Fv/Fm. And increase in chlorophyll content is caused by increased expression of synthetic genes and decreased expression of degraded genes. 2,4-EBL also decreased accumulation of Cd in S. nigrum compared with single Cd stress. According to the present results, 2,4-EBL can effectively be used to alleviate the damage of Cd stress in S. nigrum and probably in other solanaceae.
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Contaminantes del Suelo/análisis , Solanum nigrum , Antioxidantes , Biodegradación Ambiental , Cadmio/análisis , Catalasa , Malondialdehído , Raíces de Plantas/química , Superóxido DismutasaRESUMEN
BACKGROUND: Superoxide dismutase (SOD) proteins, as one kind of the antioxidant enzymes, play critical roles in plant response to various environment stresses. Even though its functions in the oxidative stress were very well characterized, the roles of SOD family genes in regulating alkaline stress response are not fully reported. METHODS: We identified the potential family members by using Hidden Markov model and soybean genome database. The neighbor-joining phylogenetic tree and exon-intron structures were generated by using software MEGA 5.0 and GSDS online server, respectively. Furthermore, the conserved motifs were analyzed by MEME online server. The syntenic analysis was conducted using Circos-0.69. Additionally, the expression levels of soybean SOD genes under alkaline stress were identified by qRT-PCR. RESULTS: In this study, we identified 13 potential SOD genes in soybean genome. Phylogenetic analysis suggested that SOD genes could be classified into three subfamilies, including MnSODs (GmMSD1-2), FeSODs (GmFSD1-5) and Cu/ZnSODs (GmCSD1-6). We further investigated the gene structure, chromosomal locations and gene-duplication, conserved domains and promoter cis-elements of the soybean SOD genes. We also explored the expression profiles of soybean SOD genes in different tissues and alkaline, salt and cold stresses, based on the transcriptome data. In addition, we detected their expression patterns in roots and leaves by qRT-PCR under alkaline stress, and found that different SOD subfamily genes may play different roles in response to alkaline stress. These results also confirmed the hypothesis that the great evolutionary divergence may contribute to the potential functional diversity in soybean SOD genes. Taken together, we established a foundation for further functional characterization of soybean SOD genes in response to alkaline stress in the future.