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1.
J Sci Food Agric ; 104(5): 3147-3155, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38072645

RESUMEN

BACKGROUND: Carotenoids play key roles in photosynthesis and are widely used in foods as natural pigments, antioxidants, and health-promoting compounds. Enhancing carotenoid production in microalgae via biotechnology has become an important area of research. RESULTS: We knocked out the Na+ /Ca2+ antiporter gene slr0681 in Synechocystis sp. PCC 6803 via homologous recombination and evaluated the effects on carotenoid production under normal (NL) and high-light (HL) conditions. On day 7 of NL treatment in calcium ion (Ca2+ )-free medium, the cell density of Δslr0681 decreased by 29% compared to the wild type (WT). After 8 days of HL treatment, the total carotenoid contents decreased by 35% in Δslr0681, and the contents of individual carotenoids were altered: myxoxanthophyll, echinenone, and ß-carotene contents increased by 10%, 50%, and 40%, respectively, while zeaxanthin contents decreased by ~40% in Δslr0681 versus the WT. The expression patterns of carotenoid metabolic pathway genes also differed: ipi expression increased by 1.2- to 8.5-fold, whereas crtO and crtR expression decreased by ~90% and 60%, respectively, in ∆slr0681 versus the WT. In addition, in ∆slr0681, the expression level of psaB (encoding a photosystem I structural protein) doubled, whereas the expression levels of the photosystem II genes psbA2 and psbD decreased by ~53% and 84%, respectively, compared to the WT. CONCLUSION: These findings suggest that slr0681 plays important roles in regulating carotenoid biosynthesis and structuring of the photosystems in Synechocystis sp. This study provides a theoretical basis for the genetic engineering of microalgae photosystems to increase their economic benefits and lays the foundation for developing microalgae germplasm resources with high carotenoid contents. © 2023 Society of Chemical Industry.


Asunto(s)
Synechocystis , Synechocystis/genética , Synechocystis/metabolismo , Proteínas Bacterianas/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Zeaxantinas/metabolismo
2.
Biochim Biophys Acta Mol Cell Res ; 1871(2): 119641, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37996057

RESUMEN

Extracellular vesicles (EVs) are cell-released vesicles that mediate intercellular communication by transferring bioactive cargo. Protein and RNA sorting into EVs has been extensively assessed, while selective enrichment of glycans in EVs remains less explored. In this study, a mass spectrometry-based approach, glycan node analysis (GNA), was applied to broadly assess the sorting of glycan features into EVs. Two metastatic variants (lung and bone) generated in mouse modes from the MDA-MB-231 human breast cancer cell line were assessed, as these EVs are known to contain distinct organotropic biomolecules. EVs were isolated from conditioned cell culture medium by tangential flow filtration and authenticated by standard techniques. GNA analysis revealed selective enrichment of several glycan features in EVs compared to the originating cells, particularly those associated with binding to the extracellular matrix, which was also observed in EVs from the parental MDA-MB-231 cell line (human pleural metastases). The bone-tropic variant displayed enrichment of distinct EV glycan features compared to the lung-tropic one. Additionally, the metastatic variants generated in mouse models displayed reduced EV glycan sorting compared to the parental metastatic cell line. This study represents the first comprehensive assessment of differences in glycan features between EVs and originating cells and provides evidence that the diversity of EV glycan sorting is reduced upon generation of variant cell lines in mouse models. Future research is likely to uncover novel mechanisms of EV glycan sorting, shed light on glycan features for EV authentication or biomarker purposes, and assess functional roles of the EV glycocode in (patho)physiology.


Asunto(s)
Neoplasias de la Mama , Vesículas Extracelulares , Humanos , Animales , Ratones , Femenino , Vesículas Extracelulares/metabolismo , Neoplasias de la Mama/metabolismo , Biomarcadores/metabolismo , Proteínas/metabolismo , Polisacáridos/análisis
3.
Front Microbiol ; 14: 1303979, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143871

RESUMEN

Arbuscular mycorrhizal fungi (AMF) have demonstrated the potential to enhance the saline-alkali tolerance in plants. Nevertheless, the extent to which AMF can ameliorate the tolerance of salt-sensitive plants to alkaline conditions necessitates further investigation. The current study is primarily centered on elucidating the impact of AMF on the growth of the Huayu22 (H22) when cultivated in saline-alkaline soil. We leveraged DNA of rhizosphere microorganisms extracted from saline-alkali soil subjected to AMF treatment and conducted high-throughput sequencing encompassing 16S rRNA gene and ITS sequencing. Our findings from high-throughput sequencing unveiled Proteobacteria and Bacillus as the prevailing phylum and genus within the bacterial population, respectively. Likewise, the predominant fungal phylum and genus were identified as Ascomycota and Haematonectria. It is noteworthy that the relative abundance of Proteobacteria, Actinobacteria, Chloroflexi, Bacteroidetes, and Ascomycota exhibited significant increments subsequent to AMF inoculation. Our investigation into soil enzyme activity revealed a remarkable surge post-AMF inoculation. Notably, the amounts of pathogen growth inhibitory enzymes and organic carbon degrading enzymes rise, as predicted by the putative roles of microbial communities. In saline-alkali soil, inoculation of AMF did boost the yield of H22. Notable improvements were observed in the weight of both 100 fruits and 100 grains, which increased by 20.02% and 22.30%, respectively. Conclusively, this study not only provides a theoretical framework but also furnishes empirical evidence supporting the utilization of AMF as a viable strategy for augmenting the yield of salt-sensitive plants grown in alkaline conditions.

4.
J Extracell Vesicles ; 12(9): e12362, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37712345

RESUMEN

The variable presence of contaminants in extracellular vesicle (EV) samples is one of the major contributors to a lack of inter-study reproducibility in the field. Well-known contaminants include protein aggregates, RNA-protein complexes and lipoproteins, which resemble EVs in shape, size and/or density. On the contrary, polysaccharides, such as hyaluronic acid (HA), have been overlooked as EV contaminants. Here, it is shown that low and medium molecular weight HA polymers are unexpectedly retained to some extent in EV fractions using two common isolation methods known for high purity: size-exclusion chromatography and tangential flow filtration. Although these isolation techniques are capable of efficient removal of non-EV-associated proteins, this is not the case for HA polymers, which are partially retained in a molecular weight-dependent manner, especially with size-exclusion chromatography. The supramolecular structure and hydrodynamic size of HA are likely to contribute to isolation in EV fractions of filtration-based approaches. Conversely, HA polymers were not retained with ultracentrifugation and polymer-based precipitation methods, which are known for co-isolating other types of contaminants. HA has a broad range of immunomodulatory effects, similar to those ascribed to various sources of EVs. Therefore, HA contaminants should be considered in future studies to avoid potential inaccurate attributions of functional effects to EVs.


Asunto(s)
Vesículas Extracelulares , Ácido Hialurónico , Reproducibilidad de los Resultados , Cromatografía en Gel , Polímeros
5.
Front Physiol ; 12: 712593, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34776998

RESUMEN

We studied the expression profile and ontogeny (from the egg stage through the larval stages and pupal stages, to the elderly adult age) of four OBPs from the silkworm moth Bombyx mori. We first showed that male responsiveness to female sex pheromone in the silkworm moth B. mori does not depend on age variation; whereas the expression of BmorPBP1, BmorPBP2, BmorGOBP1, and BmorGOBP2 varies with age. The expression profile analysis revealed that the studied OBPs are expressed in non-olfactory tissues at different developmental stages. In addition, we tested the effect of insecticide exposure on the expression of the four OBPs studied. Exposure to a toxic macrolide insecticide endectocide molecule (abamectin) led to the modulated expression of all four genes in different tissues. The higher expression of OBPs was detected in metabolic tissues, such as the thorax, gut, and fat body. All these data strongly suggest some alternative functions for these proteins other than olfaction. Finally, we carried out ligand docking studies and reported that PBP1 and GOBP2 have the capacity of binding vitamin K1 and multiple different vitamins.

6.
Zhongguo Zhong Yao Za Zhi ; 46(19): 5020-5026, 2021 Oct.
Artículo en Chino | MEDLINE | ID: mdl-34738397

RESUMEN

The chemical constituents in the ethyl acetate extract of Corydalis tomentella was isolated and purified with normal and reversed phase silica gel column chromatography, Sephadex LH-20, MCI, and semi-preparative HPLC. The compound structures were identified based on spectroscopic experiments and reported papers. Finally, eighteen compounds(1-18) were obtained from C. tomentella, including 17 alkaloids and 1 terpenoid. Among them, compound 1(tomentellaine A) was a novel alkaloid. Compounds 2-5, 7-14, and 16-18 were isolated from this plant for the first time.


Asunto(s)
Alcaloides , Corydalis , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Extractos Vegetales
7.
Health Psychol Behav Med ; 9(1): 830-857, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34650834

RESUMEN

BACKGROUND: The global COVID-19 pandemic has had a significant impact on the physical and mental health of people everywhere. The aim of the study is to understand how people living in 15 countries around the globe experience an unexpected crisis which threatens their health and that of loved ones, and how they make meaning of this disruption in their narratives. METHODS: Data were collected through an anonymous online survey during May-September 2020, which was during or just after the first wave of the COVID-19 pandemic, depending on the country. The questionnaire included demographic and three open-ended questions as prompts for stories about experiences during the initial months of the pandemic. The text was analyzed through inductive thematic content analysis and quantified for full sample description, demographic and subsequently international comparisons. RESULTS: The final qualitative dataset included stories from n = 1685 respondents. The sample was 73.6% women and 26.4% men. The mean age of participants was 39.55 years (SD = 14.71). The identified four groups of overarching themes were: The presence and absence of others; Rediscovering oneself; The meaning of daily life; Rethinking societal and environmental values. We discuss the prevalence of each theme for the sample as a whole and differences by demographic groups. The most prevalent theme referred to disruptions in interpersonal contacts, made meaningful by the increased appreciation of the value of relationships, present in (45.6%) of stories. It was more prevalent in the stories of women compared to men (χ² = 24.88, p = .001). CONCLUSIONS: The paper provides a detailed overview of the methodology, the main themes identified inductively in the stories and differences according to select demographic variables. We identify several major ways of making meaning of the pandemic. The pandemic has impacted many aspects of people's lives which give it meaning, no matter where they live.

8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-921640

RESUMEN

The chemical constituents in the ethyl acetate extract of Corydalis tomentella was isolated and purified with normal and reversed phase silica gel column chromatography, Sephadex LH-20, MCI, and semi-preparative HPLC. The compound structures were identified based on spectroscopic experiments and reported papers. Finally, eighteen compounds(1-18) were obtained from C. tomentella, including 17 alkaloids and 1 terpenoid. Among them, compound 1(tomentellaine A) was a novel alkaloid. Compounds 2-5, 7-14, and 16-18 were isolated from this plant for the first time.


Asunto(s)
Alcaloides , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Corydalis , Extractos Vegetales
9.
Huan Jing Ke Xue ; 42(1): 378-385, 2021 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-33372490

RESUMEN

A pot experiment was conducted to identify the effect of a tribasic amendment (limestone+diatomite+ferric sulfate, LDF) on chemical fractions of Cd and As in paddy soils and their accumulation in brown rice. LDF was set to seven levels (0, 0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 g·kg-1) based on the quality ratio, and two genotypes of rice were planted (Huanghuazhan and T-you 272). The results show that:① The application of LDF increased the rhizosphere soil pH of two varieties of rice, Huanghuazhan and T-you 272, by 0.01-0.42 and 0.11-0.54, respectively, and decreased the concentrations of EX-Cd by 11.1%-61.1% and 26.5%-52.9%, respectively, and the concentrations of EX-As by 8.2%-60.0% and 5.6%-49.9%, respectively. ② Application of LDF promoted the transformation of soil Cd and As from soluble to insoluble forms. Although the trends of the rhizosphere soils of the two rice varieties were not consistent, the application of LDF could decrease the proportion of EX-Cd and increase the proportion of Fe/Mn-Cd, Org-Cd, and O-Cd, which was accompanied by the reduction of the proportion of EX-As and an increase in the proportion of Ca-As. ③ The concentrations of Cd, As, and Fe in the iron plaque decreased by applying LDF, while the concentration of Mn increased, and the maximum increase of Mn could reach 124.2%. ④ Application of LDF decreased the concentrations of Cd in brown rice of the two varieties of rice by 64.6% and 65.9%, respectively, and decreased that of As by 37.0% and 42.5%, respectively. The effect on the concentrations of inorganic As was not significant. When the application amount of LDF was 2-16 g·kg-1, the concentrations of Cd and inorganic As in T-you 272 brown rice were both under 0.2 mg·kg-1, and when the application amount was 16 g·kg-1, the concentrations of Cd and inorganic As in Huanghuazhan brown rice were both under 0.2 mg·kg-1. In actual agricultural production, the application amount of LDF can be adjusted according to the soil pollution levels and the rice varieties.

10.
Genes (Basel) ; 11(4)2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32290210

RESUMEN

In this review we present the developmental, histological, evolutionary and functional properties of insect chemosensory proteins (CSPs) in insect species. CSPs are small globular proteins folded like a prism and notoriously known for their complex and arguably obscure function(s), particularly in pheromone olfaction. Here, we focus on direct functional consequences on protein function depending on duplication, expression and RNA editing. The result of our analysis is important for understanding the significance of RNA-editing on functionality of CSP genes, particularly in the brain tissue.


Asunto(s)
Evolución Biológica , Proteínas de Insectos/metabolismo , Insectos/metabolismo , Filogenia , Receptores Odorantes/metabolismo , Células Receptoras Sensoriales/metabolismo , Animales , Proteínas de Insectos/genética , Insectos/genética , Receptores Odorantes/genética
11.
PLoS One ; 13(1): e0190491, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29298333

RESUMEN

Heading date is an important agronomic trait in rice (Oryza sativa L.); it determines the geographical and seasonal adaptability of the crop. Single segment substitution lines (SSSLs) have become the preferred experimental materials in mapping functional genetic variations as the particular chromosome segments from donor genotypes can be evaluated for their impact on the phenotype in a recurrent recipient background. The phenotypic differences can be attributed to the control of quantitative trait loci (QTLs). Here, we evaluated a library consisting of 1,123 SSSLs in the same genetic background of an elite rice variety, Huajingxian74 (HJX74), and revealed four SSSLs, W05-1-11-2-7-6 (W05), W08-16-3-2 (W08), W12-28-58-03-19-1 (W12), and W22-9-5-2-4-9-3 (W22), which had a significantly different heading date compared to HJX74. To further genetically dissect the QTLs controlling heading date on chromosomes 3, 6, and 10, four SSSLs were used to develop 15 secondary SSSLs with the smaller substituted segments. The qHD-3 heading date QTL detected in W05 and W08 was delimited to an interval of 4.15 cM, whereas qHD-6-1 and qHD-6-2 heading date QTLs dissected from the substituted segments in W12 were mapped to the intervals of 2.25-cM and 2.55-cM, respectively. The qHD-10 QTL detected on the substituted segment in W22 was mapped to an interval of 6.85-cM. The nucleotide and amino acid sequence changes for those genes in the secondary SSSLs were also revealed. The allele variations of those genes might contribute to the heading date QTLs on chromosome 3 (DTH3, OsDof12, and EHD4), chromosome 6 (Hd3a, Hd17, and RFT1), and chromosome 10 (Ehd1 and Ehd2). These sequence variations in heading date genes would be useful resources for further studying the function of genes, and would be important for rice breeding. Overall, our results indicate that secondary SSSLs were powerful tools for genetic dissection of QTLs and identification of differentiation in the genes.


Asunto(s)
Cromosomas de las Plantas , Oryza/genética , Mapeo Cromosómico , Sitios de Carácter Cuantitativo
12.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-278716

RESUMEN

<p><b>OBJECTIVE</b>The study was to investigate the effect of silencing Eps8 gene expression on proliferation and apoptosis of human leukemia K562 cells and its molecular mechanism.</p><p><b>METHODS</b>The expetriments were divided into 3 groups, including blank control group(K562 cells without treatment), K562-shRNA group(K562 cells transfected by specific Eps8-shRNA lenticiral vector) and K562-NC group(K562 cells transfected by negtive control lenticiral vector). K562 cells with stably-silenced Eps8 gene were constucted by lentibirus-mediated RNA technology. The efficacy of transfection was observed by fluorescence microscopy and the changes of Eps8 mRNA and protein level were detected by RT-PCR and Western blot respectively. Cell proliferation was confirmed by typan blue exclusion and MTT method. The apoptosis rate of cells was analysed by the flow cytometry, and colony forming was detected by methylcellulose colony forming assay. The protein level change of phosphrylated-AKT were detected by Western blot.</p><p><b>RESULTS</b>Stably-silenced Eps8 gene K562 cells and the negative control cells were successfully constructed. Compared with the blank control group and the K562-NC group, the proliferation of K562-shRNA cells were siginificantly inhibited(P<0.05); the apoptosis of K562-shRNA cells increased(P<0.05). In addition, the methylcellulose colony forming assay showed that the colony forming was dramatically suppressed in K562-shRNA cells (P<0.05). Furthermore, knocking down Eps8 gene reduced the protein level of AKT phosphrylation at both residue Ser437 and Thr308(P<0.05), while there was no obvious change in the level of total-AKT(P>0.05). Knocking down Eps8 gene reduced the protein level of m-TOR phosphrylation and PRAS40 phosphrylation (P<0.05), while there was no obvious change in the level of total-mTOR and PRAS40 (P>0.05).</p><p><b>CONCLUSION</b>Silencing Eps8 gene through lentvirus can inhibit the cell proliferation and promote the apoptosis of human leukemia K562 cells, which possibly relates with the inhibition of AKT/mTOR activation.</p>

13.
PLoS One ; 11(5): e0154706, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27167733

RESUMEN

Chemosensory proteins (CSPs) are believed to play a key role in the chemosensory process in insects. Sequencing genomic DNA and RNA encoding CSP1, CSP2 and CSP3 in the sweet potato whitefly Bemisia tabaci showed strong variation between B and Q biotypes. Analyzing CSP-RNA levels showed not only biotype, but also age and developmental stage-specific expression. Interestingly, applying neonicotinoid thiamethoxam insecticide using twenty-five different dose/time treatments in B and Q young adults showed that Bemisia CSP1, CSP2 and CSP3 were also differentially regulated over insecticide exposure. In our study one of the adult-specific gene (CSP1) was shown to be significantly up-regulated by the insecticide in Q, the most highly resistant form of B. tabaci. Correlatively, competitive binding assays using tryptophan fluorescence spectroscopy and molecular docking demonstrated that CSP1 protein preferentially bound to linoleic acid, while CSP2 and CSP3 proteins rather associated to another completely different type of chemical, i.e. α-pentyl-cinnamaldehyde (jasminaldehyde). This might indicate that some CSPs in whiteflies are crucial to facilitate the transport of fatty acids thus regulating some metabolic pathways of the insect immune response, while some others are tuned to much more volatile chemicals known not only for their pleasant odor scent, but also for their potent toxic insecticide activity.


Asunto(s)
Hemípteros/crecimiento & desarrollo , Hemípteros/inmunología , Proteínas de Insectos/metabolismo , Insecticidas/toxicidad , Acroleína/análogos & derivados , Acroleína/metabolismo , Secuencia de Aminoácidos , Animales , Células Clonales , Etiquetas de Secuencia Expresada , Fluorescencia , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Hemípteros/efectos de los fármacos , Hemípteros/genética , Proteínas de Insectos/química , Proteínas de Insectos/genética , Ligandos , Ácido Linoleico/metabolismo , Simulación del Acoplamiento Molecular , Neonicotinoides , Nitrocompuestos/toxicidad , Oxazinas/toxicidad , Filogenia , Tiametoxam , Tiazoles/toxicidad , Factores de Tiempo
14.
Gene ; 576(1 Pt 2): 284-91, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26481237

RESUMEN

Bemisia tabaci Gennadius biotypes B and Q are two of the most important worldwide agricultural insect pests. Genomic sequences of Type-2 B. tabaci chemosensory protein (BtabCSP2) were cloned and sequenced in B and Q biotypes, revealing key biotype-specific variations in the intron sequence. A Q260 sequence was found specifically in Q-BtabCSP2 and Cucumis melo LN692399, suggesting ancestral horizontal transfer of gene between the insect and the plant through bacteria. A cleaved amplified polymorphic sequences (CAPS) method was then developed to differentiate B and Q based on the sequence variation in exon of BtabCSP2 gene. The performances of CSP2-based CAPS for whitefly recognition were assessed using B. tabaci field collections from Shandong Province (P.R. China). Our SacII based CAPS method led to the same result compared to mitochondrial cytochrome oxidase-based CAPS method in the field collections. We therefore propose an explanation for CSP origin and a new rapid simple molecular method based on genomic DNA and chemosensory gene to differentiate accurately the B and Q whiteflies of the Bemisia complex around the world.


Asunto(s)
Marcadores Genéticos , Hemípteros/genética , Proteínas de Insectos/genética , Animales , Secuencia de Bases , China , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Complejo IV de Transporte de Electrones/genética , Transferencia de Gen Horizontal , Variación Genética , Genética de Población , Intrones , Mitocondrias/genética , Datos de Secuencia Molecular , Filogenia
15.
Zhongguo Gu Shang ; 28(9): 864-7, 2015 Sep.
Artículo en Chino | MEDLINE | ID: mdl-26647572

RESUMEN

OBJECTIVE: To evaluate the technique and the clinical effect of folding roof and rotary pushing in treatment of children with distal radius and ulna fracture of "back to back". METHODS: From January 2012 to February 2014,38 children with distal radius and ulna fracture of "back to back" were treated by using the technique of folding roof and rotary pushing to reset and splint fixation including 23 males and 15 females with an average age of 9.5 years old ranging from 6 to 14 years old. Injury time was from 45 min to 3 days (averaged 1.3 days). All cases was unilateral closed fracture without symptoms of nerve injury occurred. The wrist joint anteroposterior and lateral radiographs showed double fracture of radius and ulna, and the broken end of radius was typical "back to back" displacement. The quality of reduction was assessed according to Dienst recommendation on the combination of Aro measurement, and the therapeutic effect was evaluated using standard of Anderson function. RESULTS: All patients were followed up from 3 to 13 months with an average of 6 months. There were no iatrogenic nerve injury. Thirty cases were treated successfully for the first time, 8 cases were again reset successfully; 28 cases were anatomical reduction, 7 cases were near anatomic reduction, 3 cases were functional reduction. At the second day 7 cases with hand and finger swelling appeared in multiple reset patients. Quality results of reduction were excellent in 33 cases, good in 5 cases. According to the standard of Anderson function evaluation, 35 cases were excellent, 3 cases were good. All fractures were healed with of deformity of wrist. CONCLUSION: Using the technique of folding roof and rotary pushing in treatment of children with distal radius and ulna fracture of "back to back" is very successful, the patient's limb function recovered well, the whole operation process is simple.


Asunto(s)
Fracturas del Radio/cirugía , Fracturas del Cúbito/cirugía , Adolescente , Niño , Femenino , Curación de Fractura , Humanos , Masculino , Fracturas del Radio/fisiopatología , Fracturas del Cúbito/fisiopatología
16.
PLoS One ; 10(3): e0121108, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25815820

RESUMEN

The relationship between salt bridges and stability/enzymatic activity is unclear. We studied this relationship by systematic alanine-scanning mutation analysis using the typical M4 family metalloprotease Pseudomonas aeruginosa elastase (PAE, also known as pseudolysin) as a model. Structural analysis revealed seven salt bridges in the PAE structure. We constructed ten mutants for six salt bridges. Among these mutants, six (Asp189Ala, Arg179Ala, Asp201Ala, Arg205Ala, Arg245Ala and Glu249Ala) were active and four (Asp168Ala, Arg198Ala, Arg253Ala, and Arg279Ala) were inactive. Five mutants were purified, and their catalytic efficiencies (kcat/Km), half-lives (t1/2) and thermal unfolding curves were compared with those of PAE. Mutants Asp189Ala and Arg179Ala both showed decreased thermal stabilities and increased activities, suggesting that the salt bridge Asp189-Arg179 stabilizes the protein at the expense of catalytic efficiency. In contrast, mutants Asp201Ala and Arg205Ala both showed slightly increased thermal stability and slightly decreased activity, suggesting that the salt bridge Asp201-Arg205 destabilizes the protein. Mutant Glu249Ala is related to a C-terminal salt bridge network and showed both decreased thermal stability and decreased activity. Furthermore, Glu249Ala showed a thermal unfolding curve with three discernable states [the native state (N), the partially unfolded state (I) and the unfolded state (U)]. In comparison, there were only two discernable states (N and U) in the thermal unfolding curve of PAE. These results suggest that Glu249 is important for catalytic efficiency, stability and unfolding cooperativity. This study represents a systematic mutational analyses of salt bridges in the model metalloprotease PAE and provides important insights into the structure-function relationship of enzymes.


Asunto(s)
Elastasa Pancreática/química , Conformación Proteica , Pseudomonas aeruginosa/enzimología , Relación Estructura-Actividad , Alanina/química , Alanina/genética , Catálisis , Estabilidad de Enzimas , Mutagénesis Sitio-Dirigida , Elastasa Pancreática/genética , Pseudomonas aeruginosa/patogenicidad , Sales (Química)/química
17.
Insect Sci ; 22(2): 203-19, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24677614

RESUMEN

We analyzed 20 chemosensory protein (CSP) genes of the silkworm Bombyx mori. We found a high number of retrotransposons inserted in introns. We then analyzed expression of the 20 BmorCSP genes across tissues using quantitative real-time polymerase chain reaction (PCR). Relatively low expression levels of BmorCSPs were found in the gut and fat body tissues. We thus tested the effects of endectocyte insecticide abamectin (B1a and B1b avermectins) on BmorCSP gene expression. Quantitative real-time PCR experiments showed that a single brief exposure to insecticide abamectin increased dramatically CSP expression not only in the antennae but in most tissues, including gut and fat body. Furthermore, our study showed coordinate expression of CSPs and metabolic cytochrome P450 enzymes in a tissue-dependent manner in response to the insecticide. The function of CSPs remains unknown. Based on our results, we suggest a role in detecting xenobiotics that are then detoxified by cytochrome P450 anti-xenobiotic enzymes.


Asunto(s)
Bombyx/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas de Insectos/metabolismo , Insecticidas/toxicidad , Ivermectina/análogos & derivados , Animales , Bombyx/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Femenino , Regulación de la Expresión Génica , Genes de Insecto , Proteínas de Insectos/genética , Ivermectina/toxicidad , Retroelementos
18.
Sheng Wu Gong Cheng Xue Bao ; 31(9): 1375-86, 2015 Sep.
Artículo en Chino | MEDLINE | ID: mdl-26955715

RESUMEN

Maize is one of the most important food crops. Rice black-streaked dwarf virus is a maize rough dwarf disease pathogen. The occurrence and transmission of maize rough dwarf disease brings great damage to maize production. The technology of using artificial miRNA to build antiviral plant has been proven effective in a variety of plants. However, such trials in maize have not been reported. We designed primers based on the sequence of maize zea-miR159a precursor and sequence of function protein genes and silencing RBSDV coding genes in RBSDV genome. We constructed amiRNA (artificial miRNA) gene for silencing RBSDV coding gene and gene silencing suppressor. We constructed pCAMBIA3301-121-amiRNA plant expression vector for transforming maize inbred lines Z31 by using agrobacterium mediated method. After molecular analysis of transgenic maize, homozygous lines with high miRNA expression were selected by molecular detection for a subsequent natural infection experiment. We studied the severity of maize rough dwarf disease according to a grading standard (grade 0 to 4). The experiment results showed that the disease resistance of transgenic homozygous maize with the anti-rough dwarf virus amiRNA vector was better than that of wild type. Among the transgenic maize, S6-miR159 transgenic maize had high disease resistance. It is feasible to create new maize variety by the use of artificial miRNA.


Asunto(s)
Resistencia a la Enfermedad/genética , MicroARNs/genética , Enfermedades de las Plantas/genética , Reoviridae/patogenicidad , Zea mays/genética , Silenciador del Gen , Vectores Genéticos , Enfermedades de las Plantas/virología , Plantas Modificadas Genéticamente/genética
19.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-251623

RESUMEN

<p><b>OBJECTIVE</b>To evaluate the technique and the clinical effect of folding roof and rotary pushing in treatment of children with distal radius and ulna fracture of "back to back".</p><p><b>METHODS</b>From January 2012 to February 2014,38 children with distal radius and ulna fracture of "back to back" were treated by using the technique of folding roof and rotary pushing to reset and splint fixation including 23 males and 15 females with an average age of 9.5 years old ranging from 6 to 14 years old. Injury time was from 45 min to 3 days (averaged 1.3 days). All cases was unilateral closed fracture without symptoms of nerve injury occurred. The wrist joint anteroposterior and lateral radiographs showed double fracture of radius and ulna, and the broken end of radius was typical "back to back" displacement. The quality of reduction was assessed according to Dienst recommendation on the combination of Aro measurement, and the therapeutic effect was evaluated using standard of Anderson function.</p><p><b>RESULTS</b>All patients were followed up from 3 to 13 months with an average of 6 months. There were no iatrogenic nerve injury. Thirty cases were treated successfully for the first time, 8 cases were again reset successfully; 28 cases were anatomical reduction, 7 cases were near anatomic reduction, 3 cases were functional reduction. At the second day 7 cases with hand and finger swelling appeared in multiple reset patients. Quality results of reduction were excellent in 33 cases, good in 5 cases. According to the standard of Anderson function evaluation, 35 cases were excellent, 3 cases were good. All fractures were healed with of deformity of wrist.</p><p><b>CONCLUSION</b>Using the technique of folding roof and rotary pushing in treatment of children with distal radius and ulna fracture of "back to back" is very successful, the patient's limb function recovered well, the whole operation process is simple.</p>


Asunto(s)
Adolescente , Niño , Femenino , Humanos , Masculino , Curación de Fractura , Fracturas del Radio , Cirugía General , Fracturas del Cúbito , Cirugía General
20.
Biotechnol Biofuels ; 7(1): 32, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24581179

RESUMEN

BACKGROUND: Polyunsaturated fatty acids (PUFAs), which contain two or more double bonds in their backbone, are the focus of intensive global research, because of their nutritional value, medicinal applications, and potential use as biofuel. However, the ability to produce these economically important compounds is limited, because it is both expensive and technically challenging to separate omega-3 polyunsaturated fatty acids (ω-3 PUFAs) from natural oils. Although the biosynthetic pathways of some plant and microalgal ω-3 PUFAs have been deciphered, current understanding of the correlation between fatty acid desaturase content and fatty acid synthesis in Synechocystis sp. PCC6803 is incomplete. RESULTS: We constructed a series of homologous vectors for the endogenous and exogenous expression of Δ6 and Δ15 fatty acid desaturases under the control of the photosynthesis psbA2 promoter in transgenic Synechocystis sp. PCC6803. We generated six homologous recombinants, harboring various fatty acid desaturase genes from Synechocystis sp. PCC6803, Gibberella fujikuroi and Mortierella alpina. These lines produced up to 8.9 mg/l of α-linolenic acid (ALA) and 4.1 mg/l of stearidonic acid (SDA), which are more than six times the corresponding wild-type levels, at 20°C and 30°C. Thus, transgenic expression of Δ6 and Δ15 fatty acid desaturases enhances the accumulation of specific ω-3 PUFAs in Synechocystis sp. PCC6803. CONCLUSIONS: In the blue-green alga Synechocystis sp. PCC6803, overexpression of endogenous and exogenous genes encoding PUFA desaturases markedly increased accumulation of ALA and SDA and decreased accumulation of linoleic acid and γ-linolenic acid. This study lays the foundation for increasing the fatty acid content of cyanobacteria and, ultimately, for producing nutritional and medicinal products with high levels of essential ω-3 PUFAs.

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