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1.
Planta ; 259(5): 112, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38581602

RESUMEN

MAIN CONCLUSION: The three, by mutagenesis produced genes OsPi21, OsXa5, and OsBADH2, generated novel lines exhibiting desired fragrance and improved resistance. Elite sterile lines are the basis for hybrid rice breeding, and rice quality and disease resistance become the focus of new sterile lines breeding. Since there are few sterile lines with fragrance and high resistance to blast and bacterial blight at the same time in hybrid rice production, we here integrated the simultaneous mutagenesis of three genes, OsPi21, OsXa5, and OsBADH2, into Zhi 5012S, an elite thermo-sensitive genic male sterile (TGMS) variety, using the CRISPR/Cas9 system, thus eventually generated novel sterile lines would exhibit desired popcorn-like fragrance and improved resistance to blast and bacterial blight but without a loss in major agricultural traits such as yield. Collectively, this study develops valuable germplasm resources for the development of two-line hybrid rice with disease resistance, which provides a way to rapid generation of novel TGMS lines with elite traits.


Asunto(s)
Sistemas CRISPR-Cas , Oryza , Oryza/genética , Resistencia a la Enfermedad/genética , Odorantes , Temperatura , Fitomejoramiento
2.
Langmuir ; 40(18): 9676-9687, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38663019

RESUMEN

Prehydrolysis liquid (PHL) from dissolving pulp and biorefinery industries is rich in saccharides and lignin, being considered as a potential source of value-added materials and platform molecules. This study proposed an environmentally friendly and simple method to prepare morphologically controllable hollow lignin nanoparticles (LNPs) and levulinic acid (LA) from PHL. In the first step, after hydrothermal treatment of PHL with p-toluenesulfonic acid (p-TsOH), lignin with a uniform molecular weight was obtained to prepare LNPs. The prepared LNPs have an obvious hollow structure, with an average size of 490-660 nm, and exhibit good stability during 30 days of storage. When the as-obtained LNPs were used as a sustained-release agent for amikacin sulfate, the encapsulation efficiency reached over 70% and the release efficiency within 40 h reached 69.2% in a pH 5.5 buffer. Subsequently, the remaining PHL that contains saccharides was directly used for LA production under the catalysis of p-TsOH. At 150 °C for 1.5 h, the LA yield reached 58.4% and remained at 56% after 5 cycles of p-TsOH. It is worth noting that only p-TsOH was used as a reactive reagent throughout the entire preparation process. Overall, this study provided a novel pathway for the integrated utilization of PHL and showed the immense potential of the preparation and application of LNPs.


Asunto(s)
Portadores de Fármacos , Ácidos Levulínicos , Lignina , Nanopartículas , Populus , Ácidos Levulínicos/química , Lignina/química , Nanopartículas/química , Populus/química , Portadores de Fármacos/química , Madera/química , Hidrólisis , Tamaño de la Partícula
3.
BMC Med Educ ; 24(1): 103, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297299

RESUMEN

OBJECTIVE: To develop a clinical learning environment scale for Chinese nursing students and test its reliability and validity. METHODS: Based on Moos social environment theory, qualitative interviews and expert consultations were used to develop a pretest version of the Chinese Nursing Students' Clinical Learning Environment Scale. With a convenience sampling method, 255 and 1582 Chinese nursing students were selected as the prediction and validation samples, respectively, from December 2022 to March 2023. Exploratory and confirmatory factor analyses were conducted to determine the construct validity. RESULTS: The scale consisted of 19 items. Exploratory factor analysis revealed three sub-scales, named goal orientation, interpersonal relation, and learning support, which explained 71.500% of the total variance. The results of the confirmatory factor analysis showed that the GFI was 0.848, the AGFI was 0.806, the RMSEA was 0.090, the RMR was 0.041, the NFI was 0.910, the IFI was 0.916, the CFI was 0.916, the PCFI was 0.798, and the PNFI was 0.793. The reliability values of the three dimensions were 0.870, 0.858, and 0.943, respectively, and the convergent validity values were 0.574, 0.603, and 0.625, respectively. CONCLUSION: The reliability and validity of the dimensions of the Chinese Nursing Students' Clinical Learning Environment Scale are acceptable, and the scale can be used as a useful tool for measuring the clinical learning environment of Chinese nursing students.


Asunto(s)
Estudiantes de Enfermería , Humanos , Psicometría , Reproducibilidad de los Resultados , Estudios Transversales , Encuestas y Cuestionarios , China
4.
Proc Biol Sci ; 290(1997): 20230406, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37072036

RESUMEN

Bird observation mainly relies on field surveys, which are time-consuming and laborious. In this study, we explored using street-view images in the virtual survey of urban birds and nests. Using the coastal city of Qingdao as the study area, 47 201 seamless spherical photos at 2741 sites were collected using the Baidu street-view (BSV) map. Single-rater-all photo checks and seven-rater-metapopulation checks were used to find inter-rater repeatability, the best viewing layer for BSV collection, and possible environments affecting the results. We also collected community science data for comparison. The BSV time machine was used to assess the temporal dynamics. Kappa square test, generalized linear model, redundancy ordination and ArcMap were used in the analysis. Different rater repeatability was 79.1% in nest evaluations and 46.9% in bird occurrence. A re-check of the different-rating photos can increase them to 92% and 70%. Seven-rater statistics showed that more than 5% sampling ratio could produce a non-significant different bird and nest percentage of the whole data, and the higher sampling ratio could reduce the variation. The middle-viewing layer survey alone could produce 93% precision of the nest checks by saving 2/3 of the time used; in birds, selecting middle and upper-view photos could find 97% of bird occurrences. In the spatial distribution, the nest's hotspot areas from this method were much greater than the community science bird-watching sites. The BSV time machine made it possible to re-check nests in the same sites but challenging the re-check of bird occurrences. The nests and birds can be observed more in the leafless season, on wide, traffic-dense coastal streets with complex vertical structures of trees, and in the gaps of tall buildings dominated by road forests. Our results indicate that BSV photos could be used to virtually evaluate bird occurrence and nests from their numbers, spatial distribution and temporal dynamics. This method provides a pre-experimental and informative supplement to large-scale bird occurrence and nest abundance surveys in urban environments.


Asunto(s)
Bosques , Comportamiento de Nidificación , Animales , Estudios de Factibilidad , Árboles , Aves
5.
Plant Physiol ; 188(1): 460-476, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34730827

RESUMEN

Lateral branches such as shoot and panicle are determining factors and target traits for rice (Oryza sativa L.) yield improvement. Cytokinin promotes rice lateral branching; however, the mechanism underlying the fine-tuning of cytokinin homeostasis in rice branching remains largely unknown. Here, we report the map-based cloning of RICE LATERAL BRANCH (RLB) encoding a nuclear-localized, KNOX-type homeobox protein from a rice cytokinin-deficient mutant showing more tillers, sparser panicles, defected floret morphology as well as attenuated shoot regeneration from callus. RLB directly binds to the promoter and represses the transcription of OsCKX4, a cytokinin oxidase gene with high abundance in panicle branch meristem. OsCKX4 over-expression lines phenocopied rlb, which showed upregulated OsCKX4 levels. Meanwhile, RLB physically binds to Polycomb repressive complex 2 (PRC2) components OsEMF2b and co-localized with H3K27me3, a suppressing histone modification mediated by PRC2, in the OsCKX4 promoter. We proposed that RLB recruits PRC2 to the OsCKX4 promoter to epigenetically repress its transcription, which suppresses the catabolism of cytokinin, thereby promoting rice lateral branching. Moreover, antisense inhibition of OsCKX4 under the LOG promoter successfully increased panicle size and spikelet number per plant without affecting other major agronomic traits. This study provides insight into cytokinin homeostasis, lateral branching in plants, and also promising target genes for rice genetic improvement.


Asunto(s)
Meristema/genética , Meristema/metabolismo , Oryza/crecimiento & desarrollo , Oryza/genética , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Metilación/efectos de los fármacos , Plantas Modificadas Genéticamente
6.
Physiol Plant ; 175(4): e13956, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37327069

RESUMEN

Melatonin is a stress-related hormone that plays a critical role in triggering the plant defence system and regulating secondary metabolism when plants are exposed to stress. To explore the potential roles of melatonin in response to Ultraviolet-B (UV-B) radiation, we examined the effects of exogenous melatonin on rosemary in vitro shoots under UV-B stress. The application of melatonin (50 µM) alleviated the adverse effects of UV-B stress on the biomass, photosynthetic pigment contents, and membrane lipids of the rosemary in vitro shoots. Melatonin significantly increased superoxide dismutase (1.15.1.1, SOD), peroxidase (1.11.1.7, POD), and catalase (1.11.1.6, CAT) activities by 62%, 99%, and 53%, respectively. The contents of total phenols, rosmarinic acid, and carnosic acid increased under UV-B stress, and they further increased by the melatonin treatment by 41%, 68%, and 67%, respectively, compared with the control group. Under UV-B stress, the increased total phenol content in melatonin-pretreated plants could be attributed to the activation of phenylalanine ammonia-lyase (4.3.1.5, PAL) and tyrosine aminotransferase (2.6.1.5, TAT). In addition, melatonin enhanced the antioxidant and antibacterial activities of the rosemary in vitro shoots under UV-B stress. These results suggest that melatonin can alleviate the damage caused by UV-B stress and also enhance the secondary metabolism and bioactivity of rosemary in vitro shoots.


Asunto(s)
Melatonina , Rosmarinus , Melatonina/farmacología , Rosmarinus/metabolismo , Biomasa , Antioxidantes/metabolismo , Fenoles/metabolismo
7.
Environ Res ; 221: 115261, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36657594

RESUMEN

Accurate information on urban forests of tree sizes, health state, community structures, and spatial distribution is still limited in African cities. Using a Google Street View (GSV)-based tree-size measuring method developed by our team, this paper aims to evaluate street trees of four African metropolitan cities using GSV data. The study compiled a large dataset with 46,016 street trees in 3454 sites in Kampala, Nairobi, Bloemfontein, and Johannesburg. The data including tree size (diameter at breast height, DBH; tree height, TH; underbranch height, UBH; canopy size), tree floristic composition (apical dominance types, broadleaf-conifer-palm leaf, flowering or not), tree health (leaf color, diebacks, dead tree, and bracket-supporting percent), streetside development (lane number, roadside shops, parking vehicle, and pedestrian density), and geolocation (latitude, longitude). These data can be spatially visualized with the help of ArcGIS, and the large dataset favors reliable maps from the street-view level. Data statistics showed that four cities were dominated by broad-leaved, apical dominance, and flowering trees, with a low level of unhealthy leaves and a tiny percentage of dead. The arbor-shrubs-herb structure vegetation dominated all four cities. Kampala had the most slender trees (DBH = 23 cm, TH = 8.4 m), while Nairobi and Johannesburg had the thickest trees (DBH = 38 cm, TH = 8.5-8.6 m). Bare land rates were lowest at 23% in Bloemfontein and highest at 33% in Nairobi. Principal analysis and Pearson correlations showed that these tree variations were closely associated with street development and local land use configuration. By comparing the urban tree data in other regions of the world, we found that the trees in African cities are generally giant but have a lower density (the trees within a 100-m street segment). Our findings emphasized that GSV data is feasible enough for urban forest monitoring in Africa, and the database is helpful for urban landscape planning and management.


Asunto(s)
Bosques , Motor de Búsqueda , Ciudades , Sudáfrica , Uganda , Kenia , Árboles
8.
Part Fibre Toxicol ; 20(1): 49, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110964

RESUMEN

BACKGROUND: Nanoplastics (NPs) are omnipresent in our lives as a new type of pollution with a tiny size. It can enter organisms from the environment, accumulate in the body, and be passed down the food chain. Inflammatory bowel disease (IBD) is a nonspecific intestinal inflammatory disease that is recurrent and prevalent in the population. Given that the intestinal features of colitis may affect the behavior and toxicity of NPs, it is imperative to clarify the risk and toxicity mechanisms of NPs in colitis models. METHODS AND RESULTS: In this study, mice were subjected to three cycles of 5-day dextran sulfate sodium (DSS) exposures, with a break of 7 to 11 days between each cycle. After the first cycle of DSS exposure, the mice were fed gavagely with water containing 100 nm polystyrene nanobeads (PS-NPs, at concentrations of 1 mg/kg·BW, 5 mg/kg·BW and 25 mg/kg·BW, respectively) for 28 consecutive days. The results demonstrated that cyclic administration of DSS induced chronic inflammation in mice, while the standard drug "5-aminosalicylic acid (5-ASA)" treatment partially improved colitis manifestations. PS-NPs exacerbated intestinal inflammation in mice with chronic colitis by activating the MAPK signaling pathway. Furthermore, PS-NPs aggravated inflammation, oxidative stress, as well as hepatic lipid metabolism disturbance in the liver of mice with chronic colitis. CONCLUSION: PS-NPs exacerbate intestinal inflammation and injury in mice with chronic colitis. This finding highlights chronically ill populations' susceptibility to environmental hazards, which urgent more research and risk assessment studies.


Asunto(s)
Colitis , Poliestirenos , Ratones , Animales , Poliestirenos/toxicidad , Poliestirenos/metabolismo , Metabolismo de los Lípidos , Colitis/inducido químicamente , Colitis/metabolismo , Inflamación/metabolismo , Estrés Oxidativo , Hígado/metabolismo , Enfermedad Crónica , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
9.
J Integr Neurosci ; 22(6): 170, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38176926

RESUMEN

BACKGROUND: Based on susceptibility-weighted imaging (SWI) visibility, deep medullary vein (DMV) scores are related to white matter damage (WMD) in patients with cerebral small vessel disease (CSVD). However, whether mechanisms are associated with DMV changes is unclear. We examined extracellular fluid (ECF) roles in white matter associations between DMV scores and white matter integrity (WMI) in patients with CSVD. METHODS: We examined magnetic resonance imaging (MRI) and clinical data from 140 patients with CSVD. DMV scores (0-18) were assigned on SWI according to DMV anatomic regions and signal continuity/visibility. WMI and ECF volumes were evaluated using free water (FW) and fractional anisotropy (FA) values by diffusion tensor imaging (DTI). RESULTS: DMV scores were independently associated with FA after adjusting for vascular risk factors, age, white matter hyperintensity (WMH) volume, and CSVD burden [ß (95% confidence interval (CI)): -0.219 (-0.375, -0.061), p = 0.006]. We also observed a significant indirect effect of DMV scores on FA in white matter (mediated by FW in white matter) after controlling for age, vascular risk factors, WMH volume, and CSVD burden. CONCLUSIONS: DMV scores were independently related to WMI and mediated by ECF in the white matter of patients with CSVD.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Imagen de Difusión Tensora , Imagen por Resonancia Magnética/métodos , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Factores de Riesgo
10.
J Environ Manage ; 344: 118375, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37356331

RESUMEN

Soil nitrogen (N) is an essential nutrient for tree growth, and excessive N is a source of pollution. This paper aims to define the effects of plant diversity and forest structure on various aspects of soil N cycling. Herein, we collected soils from 720 plots to measure total N content (TN), alkali-hydrolyzed N (AN), nitrate N (NO3--N), ammonium N (NH4+-N) in a 7.2 ha experimental forest in northeast China. Four plant diversity indices, seven structural metrics, four soil properties, and in situ N2O efflux were also measured. We found that: 1) high tree diversity had 1.3-1.4-fold NO3--N, 1.1-fold NH4+-N, and 1.5-1.8-fold N2O efflux (p < 0.05). 2) Tree growth decreased soil TN, AN, and NO3--N by more than 13%, and tree mixing and un-uniform distribution increased TN, AN, and NH4+-N by 11-22%. 3) Soil organic carbon (SOC) explained 34.3% of the N variations, followed by soil water content (1.5%), tree diameter (1.5%) and pH (1%), and soil bulk density (0.5%). SOC had the most robust linear relations to TN (R2 = 0.59) and AN (R2 = 0.5). 4) The partial least squares path model revealed that the tree diversity directly increased NO3--N, NH4+-N, and N2O efflux, and they were strengthened indirectly from soil properties by 1%-4%. The effects of tree size-density (-0.24) and spatial structure (0.16) were mainly achieved via their soil interaction and thus indirectly decreased NH4+-N, AN, and TN. Overall, high tree diversity forests improved soil N availability and N2O efflux, and un-uniform spatial tree assemblages could partially balance the soil N consumed by tree growth. Our data support soil N management in high northern hemisphere temperate forests from tree diversity and forest structural regulations.


Asunto(s)
Suelo , Árboles , Suelo/química , Carbono , Bosques , Nitrógeno/análisis , China
11.
Physiol Plant ; 174(5): e13778, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36086870

RESUMEN

Ultraviolet-B (UV-B) radiation is one of the abiotic stresses that can significantly affect the secondary metabolite accumulation in in vitro tissue cultures of medicinal plants. The present study investigated the effects of UV-B radiation on the secondary metabolites and antioxidant activities of Scutellaria baicalensis in vitro shoots grown at different concentrations of 6-benzyl aminopurine (6-BA), which is the cytokinin most widely used in plant tissue culture. The UV-B radiation caused significant increases in lipid peroxidation, total phenolic, and flavonoid contents, and antioxidant activities in the in vitro shoots grown at lower 6-BA concentrations (0 and 1 mg L-1 ), while it did not cause any significant changes in those grown at higher 6-BA concentrations (2 and 3 mg L-1 ). However, the UV-B radiation significantly altered the contents of main individual flavonoids at both lower and higher 6-BA concentrations. Upon UV-B radiation, aglycones (including baicalein, wogonin, and scutellarein) increased, while glucuronides such as baicalin and wogonoside decreased; this was more evident at higher 6-BA concentrations. This study demonstrated that the effects of UV-B radiation on the secondary metabolites of S. baicalensis in vitro shoots highly depended on the 6-BA concentration in the culture medium.


Asunto(s)
Plantas Medicinales , Scutellaria baicalensis , Antioxidantes , Flavonoides , Citocininas
12.
Appl Microbiol Biotechnol ; 106(21): 7027-7037, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36171502

RESUMEN

Atractylodes chinensis is a medicinal plant widely used for the treatment of gastric disorders, and its main bioactive compounds are atractylon and ß-eudesmol. This study was purposed to establish the adventitious root culture system of A. chinensis for in vitro production of atractylon and ß-eudesmol. The main parameters in the adventitious root induction and suspension cultures were optimized to maximize the culture efficiency. Adventitious roots were induced most efficiently from leaf explants on Murashige and Skoog (MS) solid medium containing 1.5 mg/L naphthaleneacetic acid (NAA) and 30 g/L sucrose with the highest root induction rate of approximately 92% and 12.9 roots per explant. During the adventitious root suspension culture, the root biomass and the accumulated content of the target compounds simultaneously increased to reach the maximum values after 8 weeks of culture. The maximum yield of the target compounds (total concentration 3.38 mg/g DW, total yield 2.66 mg) was achieved in the roots cultured in ½ MS liquid medium supplemented with 2.0 mg/L IBA, 3.2 mg/L NAA, and 40 g/L sucrose with the inoculum density of 8 g/L. Through the central composite design experiment, it was found that the combined use of different types of auxins in the suspension culture could further improve root growth and metabolite accumulation than the application of only one type of auxin. This work provides a new possibility to have a promising candidate for the industrial production of A. chinensis pharmaceuticals without relying on wild resources or field cultivation. KEY POINTS: • The induction culture was optimized for efficient root induction. • Suspension culture was optimized for the atractylon and ß-eudesmol production. • Combined use of different auxins improves root growth and metabolite accumulation.


Asunto(s)
Atractylodes , Raíces de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Sacarosa/metabolismo , Preparaciones Farmacéuticas/metabolismo
13.
Exp Parasitol ; 242: 108387, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36170911

RESUMEN

Plagiorchis elegans (Trematoda: Digenea) is mainly parasitic in the intestines of vertebrate animals, including humans, causing irreversible pathological damage and herd-spherical influences. However, little information is available about its molecular epidemiology, population genetics, and phylogeny. In the present study, we sequenced, assembled, and annotated the complete mitochondrial (mt) genome of P. elegans. Combining with the available mitochondrial data of subclass Digenea, phylogenetic analysis was performed based on Bayesian inference (BI). These results showed that the complete length of P. elegans is 13,862 bp, including 12 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs), and one non-coding region (NCR). There was an obvious A + T content from 61.0% to 71.3% and the values of the Ka/Ks ratio ranged from 0.119 (cox1) to 1.053 (nad6). In the BI analysis, different from previous studies, phylogenetic analysis showed genus Glypthelmins was paraphyletic rather than monophyletic and had a closer relationship with Plagiorchis and Orientocreadium. Additionally, the BI tree also presented that the genus Echinostoma was monophyletic. Our results provided molecular data in the family Plagiorchiidae proposing new insight within Xiphidiata and Echinostomata.


Asunto(s)
Echinostoma , Genoma Mitocondrial , Trematodos , Humanos , Animales , Filogenia , Teorema de Bayes , Trematodos/genética , ARN de Transferencia/genética , ARN Ribosómico/genética
14.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36361879

RESUMEN

Sucking lice are obligate ectoparasites of mammalian hosts, causing serious public health problems and economic losses worldwide. It is well known that sucking lice have fragmented mitochondrial (mt) genomes, but many remain undetermined. To better understand patterns of mt genome fragmentation in the sucking lice, we sequenced the mt genome of the buffalo louse Haematopinus tuberculatus using next-generation sequencing (NGS). The mt genome of H. tuberculatus has ten circular minichromosomes containing a total of 37 genes. Each minichromosome is 2.9-5.0 kb long and carries one to eight genes plus one large non-coding region. The number of mt minichromosomes of H. tuberculatus (ten) is different from those of congeneric species (horse louse H. asini, domestic pig louse H. suis and wild pig louse H. apri) and other sucking lice. Two events (gene translocation and merger of mt minichromosome) are observed in Haematopinus. Compared to other studies, our phylogeny generated from mt genome datasets showed a different topology, suggesting that inclusion of data other than mt genomes would be required to resolve phylogeny of sucking lice. To our knowledge, this is the first report of a ten mt minichromosomes genome in sucking lice, which opens a new outlook into unexplored mt genome fragmentation patterns in sucking lice.


Asunto(s)
Anoplura , Genoma Mitocondrial , Porcinos , Animales , Caballos/genética , Evolución Molecular , Anoplura/genética , Secuencia de Bases , Filogenia , Sus scrofa/genética
15.
Int J Mol Sci ; 23(16)2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-36012754

RESUMEN

The number of grains per panicle significantly contributes to rice yield, but the regulatory mechanism remains largely unknown. Here, we reported a loss-of-function mutant, panicle apical abortion 7 (paa7), which exhibited panicle abortion and degeneration of spikelets on the apical panicles during the late stage of young panicle development in rice. High accumulations of H2O2 in paa7 caused programmed cell death (PCD) accompanied by nuclear DNA fragmentation in the apical spikelets. Map-based cloning revealed that the 3 bp "AGC" insertion and 4 bp "TCTC" deletion mutation of paa7 were located in the 3'-UTR regions of LOC_Os07g47330, which was confirmed through complementary assays and overexpressed lines. Interestingly, LOC_Os07g47330 is known as FRIZZY PANICLE (FZP). Thus, PAA7 could be a novel allele of FZP. Moreover, the severe damage for panicle phenotype in paa7/lax2 double mutant indicated that PAA7 could crosstalk with Lax Panicle 2 (LAX2). These findings suggest that PAA7 regulates the development of apical spikelets and interacts with LAX2 to regulate panicle development in rice.


Asunto(s)
Oryza , Alelos , Peróxido de Hidrógeno/metabolismo , Oryza/metabolismo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
J Nematol ; 54(1): 20220048, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36457371

RESUMEN

Contracaecum species are zooparasitic anisakid nematodes and occur in gastrointestinal tracts of vertebrate/invertebrate animals, including humans, causing gastrointestinal pain, diarrhea, and increasingly severe vomiting. Although the complete mitochondrial (mt) genome (mitogenome) of Contracaecum sp. isolated from night herons in Beijing has been reported, the detailed information about this mt sequence is still puzzling. In the present study, we described the detailed characteristics across the complete mt DNA of Contracaecum sp., which includes 36 genes consisting of 12 protein genes, 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), and 2 noncoding regions (NCRs), and all genes have the same orientation of transcription. The AT content in the complete mitogenome of Contracaecum sp. was 72.2%, and it was the least value (66.7%) in the cox1 gene but was the highest rate (84.1%) in NCRs. The highest nucleotide diversity (Pi) among the genus Contracaecum was nad4 (0.190) and the least was cox1 (0.125), which indicates that nad4 might have the potential ability as useful markers to detect cryptic species in the genus Contracaecum or subspecies. Based on the maximum likelihood (ML) and Bayesian inference (BI) computational algorithms within subfamilies Ascaridoidea and Heterakoidea, the results supported that Contracaecum sp. was a new species and the family Ascaridiidae was paraphyletic. The complete mitogenome sequence of Contracaecum sp. supported a clear recognition of Contracaecum species and provided the potential existence of cryptic species in the genus Contracaecum. Our findings would better contribute to the surveillance, molecular epidemiology, and control of Contracaecum.

17.
Plant Physiol ; 184(1): 283-299, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32661060

RESUMEN

The thylakoid membrane is a highly complex membrane system in plants and plays crucial roles in the biogenesis of the photosynthetic apparatus and plant development. However, the genetic factors involved in chloroplast development and its relationship with intracellular metabolites are largely unknown. Here, a rice (Oryza sativa) chlorotic and necrotic leaf1 (cnl1) mutant was identified and map-based cloning revealed that a single base substitution followed by a 6-bp deletion in the ATP-binding cassette transporter I family member7 (OsABCI7) resulted in chlorotic and necrotic leaves with thylakoid membrane degradation, chlorophyll breakdown, photosynthesis impairment, and cell death in cnl1 Furthermore, the expression of OsABCI7 was inducible under lower temperatures, which severely affected cnl1 chloroplast development, and etiolated cnl1 seedlings were unable to recover to a normal green state under light conditions. Functional complementation and overexpression showed that OsABCI7 could rescue the cnl1 chlorotic and necrotic phenotype. OsABCI7 interacted with HIGH CHLOROPHYLL FLUORESCENCE222 (OsHCF222) to regulate cellular reactive oxygen species (ROS) homeostasis for thylakoid membrane stability. OsABCI7 localized to thylakoid membranes, while OsHCF222 targeted to endoplasmic reticulum and chloroplasts. Exogenous application of ascorbic acid eased the yellowish leaf phenotype by increasing chlorophyll content and alleviating ROS stress in cnl1 Unlike cnl1, the CRISPR/Cas9-mediated OsHCF222 knockout lines showed chlorotic leaves but were seedling lethal. Our results provide insight into the functions of ABC transporters in rice, especially within the relationship between ROS homeostasis and stability of thylakoid membranes.


Asunto(s)
Oryza/metabolismo , Proteínas de Plantas/metabolismo , Tilacoides/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Fotosíntesis/fisiología , Proteínas de Plantas/genética , Unión Proteica
18.
Plant Physiol ; 182(4): 2047-2064, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32029522

RESUMEN

Plant male gametogenesis is a coordinated effort involving both reproductive tissues and sporophytic tissues, in which lipid metabolism plays an essential role. Although GDSL esterases/lipases have been well known as key enzymes for many plant developmental processes and stress responses, their functions in reproductive development remain unclear. Here, we report the identification of a rice male sterile2 (rms2) mutant in rice (Oryza sativa), which is completely male sterile due to the defects in tapetum degradation, cuticle formation in sporophytic tissues, and impaired exine and central vacuole development in pollen grains. RMS2 was map-based cloned as an endoplasmic reticulum-localized GDSL lipase gene, which is predominantly transcribed during early anther development. In rms2, a three-nucleotide deletion and one base substitution (TTGT to A) occurred within the GDSL domain, which reduced the lipid hydrolase activity of the resulting protein and led to significant changes in the content of 16 lipid components and numerous other metabolites, as revealed by a comparative metabolic analysis. Furthermore, RMS2 is directly targeted by the male fertility regulators Undeveloped Tapetum1 and Persistent Tapetal Cell1 both in vitro and in vivo, suggesting that RMS2 may serve as a key node in the rice male fertility regulatory network. These findings shed light on the function of GDSLs in reproductive development and provide a promising gene resource for hybrid rice breeding.


Asunto(s)
Lipasa/metabolismo , Oryza/metabolismo , Oryza/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Lipasa/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reproducción/genética , Reproducción/fisiología
19.
J Nat Prod ; 84(5): 1515-1523, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33905250

RESUMEN

Eight prenylated xanthones including four new analogues were extracted and purified from the leaves of Garcinia xipshuanbannaensis. Multiple techniques including UV, 1D and 2D NMR, and HRESIMS were used to determine the structures of the isolated xanthones. These xanthones were evaluated for their cytotoxicity toward human cancer cells, and compound 4 exhibited activity against HeLa cells. A cytotoxic mechanism examination revealed the active compound induced cell apoptosis by arresting the cell cycle, increasing the levels of ROS, and inhibiting the expression of p-STAT3 in HeLa cells. In in vivo zebrafish experiments, compound 4 was found to block tumor proliferation and migration and have antiangiogenetic activity, and thus seems worthy of further laboratory evaluation.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antineoplásicos Fitogénicos/farmacología , Garcinia/química , Xantonas/farmacología , Inhibidores de la Angiogénesis/aislamiento & purificación , Animales , Antineoplásicos Fitogénicos/aislamiento & purificación , China , Células HeLa , Humanos , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Hojas de la Planta/química , Prenilación , Xantonas/aislamiento & purificación , Ensayos Antitumor por Modelo de Xenoinjerto , Pez Cebra
20.
World J Surg Oncol ; 19(1): 136, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33941195

RESUMEN

BACKGROUND: Mesenchymal sarcomas are tumors that originate from mesenchymal tissue. Most mesenchymal sarcomas can be accurately classified, but some are unclassifiable in clinical practice. Molecular detection methods enable patients to benefit from molecular-targeted therapies for many cancers, including lung, breast, and bowel cancers. Further, even unclassified tumors can have therapeutic targets. NTRK gene fusions are sporadic genetic alterations that occur across tumor entities. If NTRK gene fusions are detected, TRK inhibitors can be used regardless of the tumor entity. CASE PRESENTATION: This report describes a case with an unclassifiable mesenchymal sarcoma carrying a neurotrophic tyrosine receptor kinase NTRK1-KHDRBS1 gene fusion that was diagnosed and treated at multiple hospitals. Diagnostic work-up included pathological and immunohistochemical analysis, which excluded angiosarcoma, dendritic cell sarcoma, and pseudomyogenic hemangioendothelioma. The patient achieved a long-term survival without tumor relapse after treatment with crizotinib. CONCLUSIONS: This case will be of significant interest to pathologists because, despite the tumor being unclassified, a molecular target was identified. Although the FDA does not currently approve crizotinib for treatment of patients harboring NTRK gene fusions, this case provides new insights for diagnosis and treatment of mesenchymal sarcomas with NTRK1 gene translocations. Similar to ALKomas, which can be successfully treated using NTRK molecular-targeted therapy, tumors with NTRK gene translocations can be classified as NTRKomas, even when they occur at different organ sites, and with varying histological morphologies, and immunophenotypes.


Asunto(s)
Receptor trkA , Sarcoma , Proteínas Adaptadoras Transductoras de Señales , Crizotinib/uso terapéutico , Proteínas de Unión al ADN , Fusión Génica , Humanos , Recurrencia Local de Neoplasia , Proteínas de Fusión Oncogénica/genética , Pronóstico , Proteínas de Unión al ARN , Receptor trkA/genética , Sarcoma/tratamiento farmacológico , Sarcoma/genética
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