RESUMEN
Glycosylphosphatidylinositol (GPI) anchoring is a common protein modification that targets proteins to the plasma membrane (PM). Knowledge about the GPI lipid tail, which guides the secretion of GPI-anchored proteins (GPI-APs), is limited in plants. Here, we report that rice (Oryza sativa) BRITTLE CULM16 (BC16), a membrane-bound O-acyltransferase (MBOAT) remodels GPI lipid tails and governs cell wall biomechanics. The bc16 mutant exhibits fragile internodes, resulting from reduced cell wall thickness and cellulose content. BC16 is the only MBOAT in rice and is located in the endoplasmic reticulum and Golgi apparatus. Yeast gup1Δ mutant restoring assay and GPI lipid composition analysis demonstrated BC16 as a GPI lipid remodelase. Loss of BC16 alters GPI lipid structure and disturbs the targeting of BC1, a GPI-AP for cellulose biosynthesis, to the PM lipid nanodomains. Atomic force microscopy revealed compromised deposition of cellulosic nanofibers in bc16, leading to an increased Young's modulus and abnormal mechanical properties. Therefore, BC16-mediated lipid remodeling directs the GPI-APs, such as BC1, to the cell surface to fulfill multiple functions, including cellulose organization. Our work unravels a mechanism by which GPI lipids are remodeled in plants and provides insights into the control of cell wall biomechanics, offering a tool for breeding elite crops with improved support strength.
Asunto(s)
Glicosilfosfatidilinositoles , Aparato de Golgi , Glicosilfosfatidilinositoles/metabolismo , Aparato de Golgi/metabolismo , Membrana Celular/metabolismo , Saccharomyces cerevisiae/metabolismo , Aciltransferasas/metabolismo , Pared Celular/metabolismo , Celulosa/metabolismoRESUMEN
FUSCA 3 (FUS3), a seed master regulator, plays critical role in seed dormancy and oil accumulation. However, its downstream regulation mechanisms remain poorly understood. Here, we explored the roles of AINTEGUMENTA-like 6 (AIL6), a seed transcription factor, in these processes. The activation of AIL6 by FUS3 was demonstrated by dual-LUC assay. Seeds of ail6 mutants showed alterations in fatty acid compositions, and both AtAIL6 (AIL6 from Arabidopsis thaliana) and BnaAIL6 (AIL6 from Brassica napus) rescued the phenotype. Over-expression (OE) of AIL6s reversed changes in seed fatty acid composition. Notably, OE lines showed low seed germination rates down to 12% compared to 100% of wild-type Col-0. Transcriptome analysis of the mutant and an OE line indicated widespread expression changes of genes involved in lipid metabolism and phytohormone pathways. In OE mature seeds, GA4 content decreased more than 15-fold, while abscisic acid and indole-3-acetic acid (IAA) contents clearly increased. Exogenous GA3 treatments did not effectively rescue the low germination rate. Nicking seed coats increased germination rates from 25% to nearly 80% while the wild-type rdr6-11 is 100% and 98% respectively, and elongation of storage time also improved seed germination. Furthermore, dormancy imposed by AIL6 was fully released in the della quintuple mutant. Together, our results indicate AIL6 acts as a manager downstream of FUS3 in seed dormancy and lipid metabolism.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Latencia en las Plantas/genética , Proteínas de Arabidopsis/metabolismo , Giberelinas/metabolismo , Metabolismo de los Lípidos/genética , Regulación de la Expresión Génica de las Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Germinación/fisiología , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Semillas/metabolismo , Factores de Transcripción/metabolismoRESUMEN
Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health 1 . Bats have been recognized as one of the most important reservoirs for emerging viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS) 2-10 . Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.
Asunto(s)
Alphacoronavirus/aislamiento & purificación , Alphacoronavirus/patogenicidad , Enfermedades de los Animales/epidemiología , Enfermedades de los Animales/virología , Quirópteros/virología , Infecciones por Coronavirus/veterinaria , Diarrea/veterinaria , Porcinos/virología , Alphacoronavirus/clasificación , Alphacoronavirus/genética , Enfermedades de los Animales/transmisión , Animales , Biodiversidad , China/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Diarrea/patología , Diarrea/virología , Reservorios de Enfermedades/veterinaria , Reservorios de Enfermedades/virología , Genoma Viral/genética , Humanos , Yeyuno/patología , Yeyuno/virología , Filogenia , Síndrome Respiratorio Agudo Grave/epidemiología , Síndrome Respiratorio Agudo Grave/veterinaria , Síndrome Respiratorio Agudo Grave/virología , Análisis Espacio-Temporal , Zoonosis/epidemiología , Zoonosis/transmisión , Zoonosis/virologíaRESUMEN
Thyroid cancer is one of the most common endocrine malignancies in clinical practice. Traditional surgery and radioactive iodine ablation have poor treatment results for poorly differentiated thyroid cancer, and there is a risk of metastasis and recurrence. In this study, caffeic acid, a natural herbal extract with certain biological activity, has been as precursor to prepare new caffeic acid carbon nanodots via a one-step hydrothermal method. The caffeic acid carbon nanodots retains part of the structure and biological activity of caffeic acid, and have good biocompatibility, water solubility and stability. The construction of the carbon nanodots could effectively improve their bio-absorption rate and the efficacy. In vitro cell experiments showed that low-dose caffeic acid carbon nanodots had a significant inhibitory effect on poorly differentiated papillary thyroid carcinoma BCPAP cells. At low concentrations of 16 µg/mL, the inhibition rate of human thyroid cancer cells BCPAP was ~ 79%. The anti-tumor mechanism was predicted and verified by transcriptome, real-time quantitative PCR and western blot experiments. The caffeic acid carbon nanodots showed to simultaneously downregulate the expression of KRAS, p-BRAF, p-MEK1 and p-ERK1/2, the four continuous key proteins in a MAPK classical signaling pathway. In vivo experiments further confirmed the caffeic acid carbon nanodots could significantly inhibit the tumorigenicity of xenografts in papillary thyroid carcinoma at quite low doses. This piece of work provides a new nanomedicine and therapeutic strategy for highly resistant poorly differentiated papillary thyroid carcinoma.
Asunto(s)
Ácidos Cafeicos , Carbono , Ratones Desnudos , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Ácidos Cafeicos/farmacología , Ácidos Cafeicos/química , Humanos , Animales , Cáncer Papilar Tiroideo/tratamiento farmacológico , Cáncer Papilar Tiroideo/patología , Cáncer Papilar Tiroideo/metabolismo , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/patología , Línea Celular Tumoral , Carbono/química , Ratones , Ratones Endogámicos BALB C , Resistencia a Antineoplásicos/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Proliferación Celular/efectos de los fármacos , FemeninoRESUMEN
Various studies have suggested decoupling material stock from economic output as an important measure for promoting sustainable development. Here, we develop three theoretical hypotheses to describe the evolution features and economic effects of material stock intensity, and predict in theory that (1) Countries with higher material stock intensity are more likely to decouple economic growth from material stock. (2) Material stock intensity follows convergence trends. (3) Higher material stock intensity leads to higher long-run economic growth rates. To examine the adaptability of these hypotheses, we choose steel in-use stock as the proxy for the material capital stock and use panel data in 85 countries from 1950 to 2018 to conduct empirical analysis. Our empirical results in most countries support the theoretical predictions of the hypotheses. In particular, a 0.1t/k$ increase in steel stock intensity leads to a 2.12% increase in the probability of decoupling between steel stock and economic output next year and a 0.34% increase in the long-run GDP per capita growth rate annually. Moreover, steel stock intensity converges to approximately 0.25t/k$ to 0.35t/k$ at mature development stages. We predict that, except China, which is expected to follow decoupling trends, other large developing economies will couple economic output with steel stock. However, the shape of intensity curves is still uncertain for highly developed countries in the future.
Asunto(s)
Desarrollo Económico , Eficiencia , China , Acero , Desarrollo Sostenible , Dióxido de Carbono/análisisRESUMEN
ABA-INSENSITIVE 3 (ABI3) has long been known for activation of storage protein accumulation. A role of ABI3 on oil accumulation was previously suggested based on a decrease of oil content in seeds of abi3 mutant. However, this conclusion could not exclude possibilities of indirect or pleiotropic effects, such as through mutual regulatory interactions with FUSCA3 (FUS3), an activator of oil accumulation. To identify that ABI3 functions independent of the effects of related seed transcription factors, we expressed ABI3 under the control of an inducible promoter in tobacco BY2 cells and Arabidopsis rosette leaves. Inducible expression of ABI3 activated oil accumulation in these non-seed cells, demonstrating a general role of ABI3 in regulation of oil biosynthesis. Further expressing ABI3 in rosette leaves of fus3 knockout mutant still caused up to 3-fold greater triacylglycerol accumulation, indicating ABI3 can activate lipid accumulation independently of FUS3. Transcriptome analysis revealed that LIPID DROPLET PROTEIN (LDP) genes, including OLEOSINs and CALEOSINs, were up-regulated up to 1000-fold by ABI3 in the absence of FUS3, while the expression of WRINKLED1 was doubled. Taken together, our results provide genetic evidence that ABI3 activates oil accumulation with or without FUS3, most likely through up-regulating LDPs and WRINKLED1.
Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Proteínas Asociadas a Gotas Lipídicas/genética , Proteínas Asociadas a Gotas Lipídicas/metabolismo , Semillas/metabolismo , Factores de Transcripción/genéticaRESUMEN
Caleosins are lipid droplet- and endoplasmic reticulum-associated proteins. To investigate their functions in oil accumulation, expression levels of caleosins in developing seeds of Arabidopsis thaliana were examined and four seed-expressed caleosins (CLO1, CLO2, CLO4, and CLO6) were identified. The four single mutants showed similar minor changes of fatty acid composition in seeds. Two double mutants (clo1 clo2 and clo1×clo2) demonstrated distinct changes of fatty acid composition, a 16-23% decrease of oil content, and a 10-13% decrease of seed weight. Moreover, a 40% decrease of oil content, further fatty acid changes, and misshapen membranes of smaller lipid droplets were found in seeds of quadruple CLO RNAi lines. Notably, ~40% of quadruple CLO RNAi T1 seeds failed to germinate, and deformed embryos and seedlings were also observed. Complementation experiments showed that CLO1 rescued the phenotype of clo1 clo2. Overexpression of CLO1 in seedlings and BY2 cells increased triacylglycerol content up to 73.6%. Transcriptome analysis of clo1 clo2 developing seeds showed that expression levels of some genes related to lipid, embryo development, calcium signaling, and stress responses were affected. Together, these results suggest that the major seed-expressed caleosins have overlapping functions in oil accumulation and show pleiotropic effects on embryo development.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al Calcio , Desarrollo Embrionario , Ácidos Grasos/metabolismo , Regulación de la Expresión Génica de las Plantas , Aceites de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Plantones/metabolismo , SemillasRESUMEN
Acetylation, a prevalent modification of cell-wall polymers, is a tightly controlled regulatory process that orchestrates plant growth and environmental adaptation. However, due to limited characterization of the enzymes involved, it is unclear how plants establish and dynamically regulate the acetylation pattern in response to growth requirements. In this study, we identified a rice (Oryza sativa) GDSL esterase that deacetylates the side chain of the major rice hemicellulose, arabinoxylan. Acetyl esterases involved in arabinoxylan modification were screened using enzymatic assays combined with mass spectrometry analysis. One candidate, DEACETYLASE ON ARABINOSYL SIDECHAIN OF XYLAN1 (DARX1), is specific for arabinosyl residues. Disruption of DARX1 via Tos17 insertion and CRISPR/Cas9 approaches resulted in the accumulation of acetates on the xylan arabinosyl side chains. Recombinant DARX1 abolished the excess acetyl groups on arabinoxylan-derived oligosaccharides of the darx1 mutants in vitro. Moreover, DARX1 is localized to the Golgi apparatus. Two-dimensional 13C-13C correlation spectroscopy and atomic force microscopy further revealed that the abnormal acetylation pattern observed in darx1 interrupts arabinoxylan conformation and cellulose microfibril orientation, resulting in compromised secondary wall patterning and reduced mechanical strength. This study provides insight into the mechanism controlling the acetylation pattern on arabinoxylan side chains and suggests a strategy to breed robust elite crops.
Asunto(s)
Oryza/enzimología , Proteínas de Plantas/metabolismo , Xilanos/metabolismo , Acetilación , Pared Celular/metabolismo , Pared Celular/ultraestructura , Celulosa/metabolismo , Productos Agrícolas , Esterasas/genética , Esterasas/metabolismo , Aparato de Golgi/metabolismo , Aparato de Golgi/ultraestructura , Mutación , Oligosacáridos/metabolismo , Oryza/genética , Oryza/ultraestructura , Fitomejoramiento , Proteínas de Plantas/genéticaRESUMEN
Bisphenol A (BPA), an important chemical raw material, is now a ubiquitous environmental contaminant. As an endocrine disruptor similar to estrogen, BPA increases the risk of various metabolic and chronic diseases. BPA has immunotoxicity to humans and animals. 1,8-cineole (CIN) is a plant-derived monoterpene with antioxidant and antiapoptosis actions. However, there are no reports about whether CIN could antagonize the BPA-induced apoptosis and necroptosis in bursa of Fabricius (BF) of chicken. This study was to elucidate the ameliorative mechanism of CIN on the apoptosis and necroptosis in BF induced by BPA. 120 broilers (1-day-old) were randomly divided into four groups: control group, CIN group, CIN and BPA co-treatment group, and BPA group. TUNEL analysis results, histopathological variations, and the overexpression of proapoptosis biomakers (Caspase 3, Bax, Cyt-c, and p53) and necroptosis pathway-related factors (RIPK1, RIPK3, MLKL, and FADD) indicated that BPA exposure induced the apoptosis and necroptosis in chicken BF. Moreover, BPA treatment elevated the levels of oxidative stress indexes (MDA, iNOS, and NO) and weaken antioxidases activity (SOD, GPx, and CAT) and total antioxidant capacity in chicken BF. BPA administration also lessened the expression of PI3K and AKT and promoted HSPs (HSP27, HSP40, HSP60, and HSP70) activation. whereas CIN supplementation prominently mitigated BPA-caused these changes and the apoptosis and necroptosis damages. In brief, this study illuminated that CIN could protect the chicken BF against BPA-induced apoptosis and necroptosis through restraining oxidative stress and activating PI3K/AKT pathway.
Asunto(s)
Bolsa de Fabricio , Necroptosis , Animales , Apoptosis , Compuestos de Bencidrilo , Bolsa de Fabricio/metabolismo , Pollos/metabolismo , Eucaliptol/metabolismo , Estrés Oxidativo , Fenoles , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
During growth, plant cells must coordinate cell expansion and cell wall reinforcement by integrating distinct regulatory pathways in concert with intrinsic and external cues. However, the mechanism underpinning this integration is unclear, as few of the regulators that orchestrate cell expansion and wall strengthening have been identified. Here, we report a rice (Oryza sativa) Class II KNOX-like homeobox protein, KNOTTED ARABIDOPSIS THALIANA7 (KNAT7), that interacts with different partners to govern cell expansion and wall thickening. A loss-of-function mutation in KNAT7 enhanced wall mechanical strength and cell expansion, resulting in improved lodging resistance and grain size. Overexpression of KNAT7 gave rise to the opposite phenotypes, with plants having weaker cell walls and smaller grains. Biochemical and gene expression analyses revealed that rice KNAT7 interacts with a secondary wall key regulator, NAC31, and a cell growth master regulator, Growth-Regulating Factor 4 (GRF4). The KNAT7-NAC31 and KNAT7-GRF4 modules suppressed regulatory pathways of cell expansion and wall reinforcement, as we show in internode and panicle development. These modules function in sclerenchyma fiber cells and modulate fiber cell length and wall thickness. Hence, our study uncovers a mechanism for the combined control of cell size and wall strengthening, providing a tool to improve lodging resistance and yield in rice production.
Asunto(s)
Pared Celular/fisiología , Proteínas de Homeodominio/fisiología , Oryza/fisiología , Proteínas de Arabidopsis , Proteínas Represoras , Semillas/crecimiento & desarrolloRESUMEN
Acetylation is a ubiquitous modification on cell wall polymers, which play a structural role in plant growth and stress defenses. However, the mechanisms for how crop plants accomplish cell wall polymer O-acetylation are largely unknown. Here, we report on the isolation and characterization of two trichome birefringence-like (tbl) mutants in rice (Oryza sativa), which are affected in xylan O-acetylation. ostbl1 and ostbl2 single mutant and the tbl1 tbl2 double mutant displayed a stunted growth phenotype with varied degree of dwarfism. As shown by chemical assays, the wall acetylation level is affected in the mutants and the knock-down and overexpression transgenic plants. Furthermore, NMR spectroscopy analyses showed that all those mutants have varied decreases in xylan monoacetylation. The divergent expression levels of OsTBL1 and OsTBL2 explained the chemotype difference and indicated that OsTBL1 is a functionally dominant gene. OsTBL1 was found to be Golgi-localized. The recombinant OsTBL1 protein incorporates acetyl groups onto xylan. By using xylopentaose, a preferred acceptor substrate, OsTBL1 can transfer up to four acetyl residues onto xylopentaose, and this activity showed saturable kinetics. 2D-NMR spectroscopy showed that OsTBL1 transfers acetate to both 2-O and 3-O sites of xylosyl residues. In addition, ostbl1 and tbl1 tbl2 displayed susceptibility to rice blight disease, indicating that this xylan modification is required for pathogen resistance. This study identifies the major genes responsible for xylan acetylation in rice plants.
Asunto(s)
Oryza/metabolismo , Oryza/microbiología , Proteínas de Plantas/metabolismo , Xilanos/metabolismo , Acetilación , Acetiltransferasas/genética , Acetiltransferasas/metabolismo , Birrefringencia , Regulación de la Expresión Génica de las Plantas , Aparato de Golgi/metabolismo , Mutación , Oryza/genética , Filogenia , Enfermedades de las Plantas/microbiología , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Tricomas/metabolismo , Xilanos/genéticaRESUMEN
Cellulose, which can be converted into numerous industrial products, has important impacts on the global economy. It has long been known that cellulose synthesis in plants is tightly regulated by various phytohormones. However, the underlying mechanism of cellulose synthesis regulation remains elusive. Here, we show that in rice (Oryza sativa), gibberellin (GA) signals promote cellulose synthesis by relieving the interaction between SLENDER RICE1 (SLR1), a DELLA repressor of GA signaling, and NACs, the top-layer transcription factors for secondary wall formation. Mutations in GA-related genes and physiological treatments altered the transcription of CELLULOSE SYNTHASE genes (CESAs) and the cellulose level. Multiple experiments demonstrated that transcription factors NAC29/31 and MYB61 are CESA regulators in rice; NAC29/31 directly regulates MYB61, which in turn activates CESA expression. This hierarchical regulation pathway is blocked by SLR1-NAC29/31 interactions. Based on the results of anatomical analysis and GA content examination in developing rice internodes, this signaling cascade was found to be modulated by varied endogenous GA levels and to be required for internode development. Genetic and gene expression analyses were further performed in Arabidopsis thaliana GA-related mutants. Altogether, our findings reveal a conserved mechanism by which GA regulates secondary wall cellulose synthesis in land plants and provide a strategy for manipulating cellulose production and plant growth.
Asunto(s)
Celulosa/biosíntesis , Genes de Plantas/fisiología , Giberelinas/fisiología , Oryza/fisiología , Reguladores del Crecimiento de las Plantas/fisiología , Transducción de Señal/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Glucosiltransferasas/genética , Glucosiltransferasas/fisiología , Oryza/metabolismo , Proteínas de Plantas/fisiologíaRESUMEN
Due to its highly autonomy, the strapdown inertial navigation system (SINS) is widely used in unmanned underwater vehicles (UUV) navigation. Initial alignment is crucial because the initial alignment results will be used as the initial SINS value, which might affect the subsequent SINS results. Due to the rapid convergence of Earth meridians, there is a calculation overflow in conventional initial alignment algorithms, making conventional initial algorithms are invalid for polar UUV navigation. To overcome these problems, a polar initial alignment algorithm for UUV is proposed in this paper, which consists of coarse and fine alignment algorithms. Based on the principle of the conical slow drift of gravity, the coarse alignment algorithm is derived under the grid frame. By choosing the velocity and attitude as the measurement, the fine alignment with the Kalman filter (KF) is derived under the grid frame. Simulation and experiment are realized among polar, conventional and transversal initial alignment algorithms for polar UUV navigation. Results demonstrate that the proposed polar initial alignment algorithm can complete the initial alignment of UUV in the polar region rapidly and accurately.
RESUMEN
Cellulose represents the most abundant biopolymer in nature and has great economic importance. Cellulose chains pack laterally into crystalline forms, stacking into a complicated crystallographic structure. However, the mechanism of cellulose crystallization is poorly understood. Here, via functional characterization, we report that Brittle Culm1 (BC1), a COBRA-like protein in rice, modifies cellulose crystallinity. BC1 was demonstrated to be a glycosylphosphatidylinositol (GPI) anchored protein and can be released into cell walls by removal of the GPI anchor. BC1 possesses a carbohydrate-binding module (CBM) at its N-terminus. In vitro binding assays showed that this CBM interacts specifically with crystalline cellulose, and several aromatic residues in this domain are essential for binding. It was further demonstrated that cell wall-localized BC1 via the CBM and GPI anchor is one functional form of BC1. X-ray diffraction (XRD) assays revealed that mutations in BC1 and knockdown of BC1 expression decrease the crystallite width of cellulose; overexpression of BC1 and the CBM-mutated BC1s caused varied crystallinity with results that were consistent with the in vitro binding assay. Moreover, interaction between the CBM and cellulose microfibrils was largely repressed when the cell wall residues were pre-stained with two cellulose dyes. Treating wild-type and bc1 seedlings with the dyes resulted in insensitive root growth responses in bc1 plants. Combined with the evidence that BC1 and three secondary wall cellulose synthases (CESAs) function in different steps of cellulose production as revealed by genetic analysis, we conclude that BC1 modulates cellulose assembly by interacting with cellulose and affecting microfibril crystallinity.
Asunto(s)
Celulosa/química , Glicosilfosfatidilinositoles/química , Microfibrillas/química , Oryza/química , Secuencia de Aminoácidos , Pared Celular/genética , Pared Celular/metabolismo , Celulosa/genética , Clonación Molecular , Cristalización , Cristalografía por Rayos X , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Glicosilfosfatidilinositoles/genética , Glicosilfosfatidilinositoles/metabolismo , Espectroscopía de Resonancia Magnética , Microfibrillas/genética , Mutación , Oryza/genética , Oryza/metabolismoRESUMEN
The ribosome is the basic machinery for translation, and biogenesis of ribosomes involves many coordinated events. However, knowledge about ribosomal dynamics in higher plants is very limited. This study chose a highly conserved trans-factor, the 60S ribosomal subunit nuclear export adaptor NMD3, to characterize the mechanism of ribosome biogenesis in the monocot plant Oryza sativa (rice). O. sativa NMD3 (OsNMD3) shares all the common motifs and shuttles between the nucleus and cytoplasm via CRM1/XPO1. A dominant negative form of OsNMD3 with a truncated nuclear localization sequence (OsNMD3(ΔNLS)) was retained in the cytoplasm, consequently interfering with the release of OsNMD3 from pre-60S particles and disturbing the assembly of ribosome subunits. Analyses of the transactivation activity and cellulose biosynthesis level revealed low protein synthesis efficiency in the transgenic plants compared with the wild-type plants. Pharmaceutical treatments demonstrated structural alterations in ribosomes in the transgenic plants. Moreover, global expression profiles of the wild-type and transgenic plants were investigated using the Illumina RNA sequencing approach. These expression profiles suggested that overexpression of OsNMD3(ΔNLS) affected ribosome biogenesis and certain basic pathways, leading to pleiotropic abnormalities in plant growth. Taken together, these results strongly suggest that OsNMD3 is important for ribosome assembly and the maintenance of normal protein synthesis efficiency.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Unión al ARN/genética , Secuencia de Aminoácidos , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulación del Desarrollo de la Expresión Génica , Datos de Secuencia Molecular , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Fenotipo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/química , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/metabolismo , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Golgi-localized nucleotide sugar transporters (NSTs) are considered essential for the biosynthesis of wall polysaccharides and glycoproteins based on their characteristic transport of a large number of nucleotide sugars to the Golgi lumen. The lack of NST mutants in plants has prevented evaluation of this hypothesis in plants. A previously undescribed Golgi NST mutant, brittle culm14 (bc14), displays reduced mechanical strength caused by decreased cellulose content and altered wall structure, and exhibits abnormalities in plant development. Map-based cloning revealed that all of the observed mutant phenotypes result from a missense mutation in a putative NST gene, Oryza sativa Nucleotide Sugar Transporter1 (OsNST1). OsNST1 was identified as a Golgi-localized transporter by analysis of a fluorescence-tagged OsNST1 expressed in rice protoplast cells and demonstration of UDP-glucose transport activity via uptake assays in yeast. Compositional sugar analyses in total and fractionated wall residues of wild-type and bc14 culms showed a deficiency in the synthesis of glucoconjugated polysaccharides in bc14, indicating that OsNST1 supplies the glucosyl substrate for the formation of matrix polysaccharides, and thereby modulates cellulose biosynthesis. OsNST1 is ubiquitously expressed, with high expression in mechanical tissues. The inferior mechanical strength and abnormal development of bc14 plants suggest that OsNST1 has pleiotropic effects on cell wall biosynthesis and plant growth. Identification of OsNST1 has improved our understanding of how cell wall polysaccharide synthesis is regulated by Golgi NSTs in plants.
Asunto(s)
Pared Celular/metabolismo , Aparato de Golgi/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Oryza/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Polisacáridos/biosíntesis , Transporte Biológico/fisiología , Pared Celular/genética , Clonación Molecular , Aparato de Golgi/genética , Proteínas de Transporte de Membrana/genética , Mutación Missense , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Polisacáridos/genéticaRESUMEN
Background: Heart failure (HF) and colorectal cancer are significant public health concerns with substantial morbidity and mortality. Previous studies have indicated a close association between HF and various tumors, including colorectal cancer. Further understanding the potential causal relationship between them could provide insights into their shared pathophysiological mechanisms and inform strategies for prevention and treatment. Methods: This study employed a bidirectional Mendelian randomization (MR) approach using genetic variants from large genome-wide association studies (GWAS) as instrumental variables (IVs). The inverse-variance weighted (IVW) method was employed for the MR analysis. Meta-analyses of IVW results from discovery and validation cohorts were performed to enhance the power of detecting causal effects. Sensitivity analyses, including heterogeneity analysis and tests for horizontal pleiotropy, were conducted to test the robustness of the conclusions. Results: Results from the discovery cohort suggest HF is associated with an approximately 30% increased risk of colorectal cancer (OR 1.32, 95% CI 1.03-1.69, P=0.025), although this finding did not reach statistical significance in the validation cohort (OR 1.19, 95% CI 0.97-1.46, P=0.090). However, meta-analysis supports HF as a potential risk factor for colorectal cancer (Pooled OR 1.24, 95% CI 1.06-1.25, P=0.007). Reverse MR analysis found no evidence of colorectal cancer increasing HF risk (Pooled OR 1.03, 95% CI 0.99-1.07, P=0.121). Sensitivity analyses (all P>0.05) indicate robustness against heterogeneity and horizontal pleiotropy. Conclusion: This comprehensive bidirectional MR study provides genetic evidence supporting a causal link between HF and colorectal cancer. The insights gained enhance understanding of their interconnectedness and may guide future research and clinical practices aimed at mitigating their risks through targeted interventions.
Asunto(s)
Neoplasias Colorrectales , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Insuficiencia Cardíaca , Análisis de la Aleatorización Mendeliana , Humanos , Neoplasias Colorrectales/genética , Insuficiencia Cardíaca/genética , Polimorfismo de Nucleótido Simple , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/etiología , Factores de Riesgo , MultiómicaRESUMEN
The synthesis of materials with a multicomponent hierarchical structure is an essential strategy for achieving high-performance electromagnetic wave (EMW) absorption. However, conventional design strategies face challenges in terms of the rational construction of specific architecture. In this study, we employ a combined space-restricted and hierarchical construction strategy to surface-plant MoS2 nanosheets on yolk-shell structural carbon-modified Co-based composites, leading to the development of high-performance Co/NC@void@C@MoS2 absorbers with advanced architecture. The surface-planted MoS2 nanosheets, the Co/NC magnetic yolk, and the dielectric carbon shell work together to enhance the impedance matching characteristics and synergistic loss capabilities in the composites. Experimental results indicate that Co/NC@void@C-700@MoS2 exhibited the best absorption performance with an effective absorption bandwidth of 7.54 GHz (at 2.05 mm) and a minimum reflection loss of -60.88 dB (at 1.85 mm). Furthermore, radar cross-section simulation results demonstrate that Co/NC@void@C-700@MoS2 effectively suppresses the scattering and transmission of EMWs on perfect electric conductor substrates, implying its superior practical application value. This study provides inspiration and experimental basis for designing and optimizing EMW absorption materials with hierarchical yolk-shell architecture.
RESUMEN
The rational and effective combination of multicomponent materials and the design of subtle microstructure for efficient microwave absorption are still challenging. In this study, carbon-coated CoFe with heterogeneous interfaces was space-restricted in the void space of hollow mesoporous carbon spheres through a facile approach involving electrostatic adsorption and annealing, and a high-performance microwave absorber (MAs) (denoted as Co0.7Fe0.3@C@void@C) was successfully prepared. The heterostructure, three-dimensional lightweight porous morphology, and electromagnetic synergy strategy enabled the Co0.7Fe0.3@C@void@C material with yolk-shell structure to exhibit surprising microwave absorption properties. When the annealing temperature and filler loading were 550° C and 15 wt%, respectively, the composites exhibited an effective absorption bandwidth (EAB) of 7.16 GHz at 2.48 mm and a minimum reflection loss of -24.1 dB at 2.11 mm. A maximum EAB of 7.21 GHz at 2.37 mm could be achieved for the composite prepared with an annealing temperature of 650° C. In addition, radar cross-section experiments demonstrated, the potential practical applicability of Co0.7Fe0.3@C@void@C. This work expands a new avenue to develop high-performance and lightweight MAs with ingenious microstructure.
RESUMEN
BACKGROUND: In addition to the diameters of pulmonary nodules, the number and morphology of blood vessels in pure ground-glass nodules (pGGNs) were closely related to the occurrence of lung cancer. Moreover, the benign and malignant signs of nodules were also valuable for the identification of nodules. Based on these two points, we tried to revise Lung-RADS 2022 and proposed our Modified Lung-RADS. The aim of the study was to verify the diagnostic performance of Modified Lung-RADS for pulmonary solid nodules (SNs) and pure ground-glass nodules (pGGNs) in patients with previous malignancies. METHODS: The chest CT and clinical data of patients with prior cancer who underwent pulmonary nodulectomies from 1 January 2018 to 30 November 2021 were enrolled according to inclusion and exclusion criteria. A total of 240 patients with 293 pulmonary nodules were included in this study. In contrast with the original version, the risk classification of pGGNs based on the GGN-vascular relationships (GVRs), and the SNs without burrs and with benign signs, could be downgraded to category 2. The sensitivity, specificity, and agreement rate of the original Lung-RADS 2022 and Modified Lung-RADS for pGGNs and SNs were calculated and compared. RESULTS: Compared with the original version, the sensitivity and agreement rate of the Modified version for pGGNs increased from 0 and 23.33% to 97.10% and 92.22%, respectively, while the specificity decreased from 100% to 76.19%. As regards SNs, the specificity and agreement rate of the Modified version increased from 44.44% to 75.00% (p < 0.05) and 88.67% to 94.09% (p = 0.052), respectively, while the sensitivity was unchanged (98.20%). CONCLUSIONS: In general, the diagnostic efficiency of Modified Lung-RADS was superior to that of the original version, and Modified Lung-RADS could be a preliminary attempt to improve Lung-RADS 2022.