RESUMO
While polygenic risk scores (PRSs) enable early identification of genetic risk for chronic obstructive pulmonary disease (COPD), predictive performance is limited when the discovery and target populations are not well matched. Hypothesizing that the biological mechanisms of disease are shared across ancestry groups, we introduce a PrediXcan-derived polygenic transcriptome risk score (PTRS) to improve cross-ethnic portability of risk prediction. We constructed the PTRS using summary statistics from application of PrediXcan on large-scale GWASs of lung function (forced expiratory volume in 1 s [FEV1] and its ratio to forced vital capacity [FEV1/FVC]) in the UK Biobank. We examined prediction performance and cross-ethnic portability of PTRS through smoking-stratified analyses both on 29,381 multi-ethnic participants from TOPMed population/family-based cohorts and on 11,771 multi-ethnic participants from TOPMed COPD-enriched studies. Analyses were carried out for two dichotomous COPD traits (moderate-to-severe and severe COPD) and two quantitative lung function traits (FEV1 and FEV1/FVC). While the proposed PTRS showed weaker associations with disease than PRS for European ancestry, the PTRS showed stronger association with COPD than PRS for African Americans (e.g., odds ratio [OR] = 1.24 [95% confidence interval [CI]: 1.08-1.43] for PTRS versus 1.10 [0.96-1.26] for PRS among heavy smokers with ≥ 40 pack-years of smoking) for moderate-to-severe COPD. Cross-ethnic portability of the PTRS was significantly higher than the PRS (paired t test p < 2.2 × 10-16 with portability gains ranging from 5% to 28%) for both dichotomous COPD traits and across all smoking strata. Our study demonstrates the value of PTRS for improved cross-ethnic portability compared to PRS in predicting COPD risk.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Transcriptoma , Humanos , Pulmão , National Heart, Lung, and Blood Institute (U.S.) , Doença Pulmonar Obstrutiva Crônica/genética , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
Ascorbic acid (AsA) is a multifunctional phytonutrient that is essential for the human diet as well as plant development. While much is known about AsA biosynthesis in plants, how this process is regulated in tomato (Solanum lycopersicum) fruits remains unclear. Here, we found that auxin treatment inhibited AsA accumulation in the leaves and pericarps of tomato. The auxin response factor gene SlARF4 is induced by auxin to mediate auxin-induced inhibition of AsA accumulation. Specifically, SlARF4 transcriptionally inhibits the transcription factor gene SlMYB11, thereby modulating AsA accumulation by regulating the transcription of the AsA biosynthesis genes l-galactose-1-phosphate phosphatase, l-galactono-1,4-lactone dehydrogenase, and dehydroascorbate. By contrast, abscisic acid (ABA) treatment increased AsA accumulation in tomato under drought stress. ABA induced the expression of the mitogen-activated protein kinase gene SlMAPK8. We demonstrate that SlMAPK8 phosphorylates SlARF4 and inhibits its transcriptional activity, whereas SlMAPK8 phosphorylates SlMYB11 and activates its transcriptional activity. SlMAPK8 functions in ABA-induced AsA accumulation and drought stress tolerance. Moreover, ABA antagonizes the effects of auxin on AsA biosynthesis. Therefore, auxin- and ABA-induced regulation of AsA accumulation is mediated by the SlMAPK8-SlARF4-SlMYB11 module in tomato during fruit development and drought stress responses, shedding light on the roles of phytohormones in regulating AsA accumulation to mediate stress tolerance.
Assuntos
Ácido Abscísico , Ácido Ascórbico , Secas , Ácidos Indolacéticos , Proteínas de Plantas , Solanum lycopersicum , Estresse Fisiológico , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Ácido Ascórbico/biossíntese , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: Preserved ratio impaired spirometry (PRISm) is defined as a forced expiratory volume in 1â s (FEV1) <80% predicted and FEV1/forced vital capacity ≥0.70. PRISm is associated with respiratory symptoms and comorbidities. Our objective was to discover novel genetic signals for PRISm and see if they provide insight into the pathogenesis of PRISm and associated comorbidities. METHODS: We undertook a genome-wide association study (GWAS) of PRISm in UK Biobank participants (Stage 1), and selected single nucleotide polymorphisms (SNPs) reaching genome-wide significance for replication in 13 cohorts (Stage 2). A combined meta-analysis of Stage 1 and Stage 2 was done to determine top SNPs. We used cross-trait linkage disequilibrium score regression to estimate genome-wide genetic correlation between PRISm and pulmonary and extrapulmonary traits. Phenome-wide association studies of top SNPs were performed. RESULTS: 22 signals reached significance in the joint meta-analysis, including four signals novel for lung function. A strong genome-wide genetic correlation (rg) between PRISm and spirometric COPD (rg=0.62, p<0.001) was observed, and genetic correlation with type 2 diabetes (rg=0.12, p=0.007). Phenome-wide association studies showed that 18 of 22 signals were associated with diabetic traits and seven with blood pressure traits. CONCLUSION: This is the first GWAS to successfully identify SNPs associated with PRISm. Four of the signals, rs7652391 (nearest gene MECOM), rs9431040 (HLX), rs62018863 (TMEM114) and rs185937162 (HLA-B), have not been described in association with lung function before, demonstrating the utility of using different lung function phenotypes in GWAS. Genetic factors associated with PRISm are strongly correlated with risk of both other lung diseases and extrapulmonary comorbidity.
Assuntos
Diabetes Mellitus Tipo 2 , Doença Pulmonar Obstrutiva Crônica , Humanos , Estudo de Associação Genômica Ampla , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/genética , Diabetes Mellitus Tipo 2/genética , Pulmão , Volume Expiratório Forçado/genética , Espirometria , Capacidade VitalRESUMO
Type 1 diabetes is an autoimmune disease in which one's own immune system destroys insulin-secreting beta cells in the pancreas. This process results in life-long dependence on exogenous insulin for survival. Both genetic and environmental factors play a role in disease initiation, progression, and ultimate clinical diagnosis of type 1 diabetes. This review will provide background on the natural history of type 1 diabetes and the role of genetic factors involved in the complement system, as several recent studies have identified changes in levels of these proteins as the disease evolves from pre-clinical through to clinically apparent disease.
Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 1/genética , Pâncreas/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismoRESUMO
The Chinese revered a species of aquatic reptile known as Pelodiscus sinensis as both an edible and medicinal species. When artificially breeding, many deaths occurred at the farmed P. sinensis, mainly due to excessive breeding density, water contamination, and turtles biting each other secondary to bacterial infections. In this study, an isolate of gram-negative bacteria WH0623 was isolated from the liver and kidney of diseased P. sinensis to trace the potential pathogen of this disease. Based on biochemical characteristics and 16S rRNA gene sequencing analyses, this isolated strain of WH0623 was identified as Chryseobacterium indologenes. The strain's median lethal dose (LD50 ) was 3.3 × 105 colony-forming units (CFU)/g per fish weight tested using artificial infection. Histopathological analysis revealed pathological changes, including cell swelling, hyperaemia, and necrosis in many tissues. Antibiotic susceptibility tests revealed that the bacteria WH0623 was susceptible to doxycycline, sulphonamides, ceftazidime, norfloxacin, and ciprofloxacin. These antibiotics could treat the disease. In conclusion, the pathogen causing the death of farmed P. sinensis was isolated and identified, and a drug-sensitive test was conducted. Our findings contribute to the future diagnosis and treatment of the disease.
Assuntos
Doenças dos Peixes , Tartarugas , Animais , RNA Ribossômico 16S/genética , Doenças dos Peixes/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Tartarugas/genéticaRESUMO
Aeromonas jandaei is a gram-negative bacterium commonly found in aquatic environments and can induce illnesses in amphibians, reptiles and aquatic animals. In this study, a strain of bacteria was isolated from the diseased Chinese soft-shell turtle (Pelodiscus sinensis), then named strain JDP-FX. This isolate was identified as A. jandaei after analysis of morphological, physiological and biochemical characteristics, as well as 16S rRNA and gyrB gene sequences. Virulence genetic testing further detected temperature-sensitive protease (eprCAI), type III secretion system (TTSS) (ascv), nuclease (nuc), cytotonic enterotoxin (alt) and serine proteinase (ser) in JDP-FX. Compared with healthy Chinese soft-shell turtle, the serum levels of total protein (TP), albumin (ALB) and globulin (GLB) were significantly decreased in the diseased Chinese soft-shell turtle, while, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were significantly increased. Histopathological observations showed that multiple tissues, including intestinal mucosa, liver and kidney, were severely damaged in the diseased Chinese soft-shell turtle. Moreover, the diseased Chinese soft-shell turtle had significant cell degeneration, necrosis, sloughing and interstitial inflammatory cell infiltration. The pathogenicity of JDP-FX was tested via artificial infection. The median lethal dosage (LD50 ) of the strain was 1.05 × 105 colony forming units (CFU/g) per weight of Chinese soft-shell turtle. Drug susceptibility analysis revealed that JDP-FX was susceptible to ceftazidime, minocycline, cefoperazone, ceftriaxone and piperacillin. In addition, JDP-FX was resistant to doxycycline, florfenicol, sulfonamides, gentamicin, ampicillin and neomycin. Therefore, this study may provide guidance for further research into the diagnosis, prevention and treatment of JDP-FX infection.
Assuntos
Aeromonas , Doenças dos Peixes , Tartarugas , Animais , Tartarugas/genética , Tartarugas/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , ChinaRESUMO
Fringe projection profilometry (FPP), with benefits such as high precision and a large depth of field, is a popular 3D optical measurement method widely used in precision reconstruction scenarios. However, the pixel brightness at reflective edges does not satisfy the conditions of the ideal pixel-wise phase-shifting model due to the influence of scene texture and system defocus, resulting in severe phase errors. To address this problem, we theoretically analyze the non-pixel-wise phase propagation model for texture edges and propose a reprojection strategy based on scene texture modulation. The strategy first obtains the reprojection weight mask by projecting typical FPP patterns and calculating the scene texture reflection ratio, then reprojects stripe patterns modulated by the weight mask to eliminate texture edge effects, and finally fuses coarse and refined phase maps to generate an accurate phase map. We validated the proposed method on various texture scenes, including a smooth plane, depth surface, and curved surface. Experimental results show that the root mean square error (RMSE) of the phase at the texture edge decreased by 53.32%, proving the effectiveness of the reprojection strategy in eliminating depth errors at texture edges.
RESUMO
BACKGROUND: SARS-CoV-2, the causal agent of COVID-19, enters human cells using the ACE2 (angiotensin-converting enzyme 2) protein as a receptor. ACE2 is thus key to the infection and treatment of the coronavirus. ACE2 is highly expressed in the heart and respiratory and gastrointestinal tracts, playing important regulatory roles in the cardiovascular and other biological systems. However, the genetic basis of the ACE2 protein levels is not well understood. METHODS: We have conducted the largest genome-wide association meta-analysis of plasma ACE2 levels in >28 000 individuals of the SCALLOP Consortium (Systematic and Combined Analysis of Olink Proteins). We summarize the cross-sectional epidemiological correlates of circulating ACE2. Using the summary statistics-based high-definition likelihood method, we estimate relevant genetic correlations with cardiometabolic phenotypes, COVID-19, and other human complex traits and diseases. We perform causal inference of soluble ACE2 on vascular disease outcomes and COVID-19 severity using mendelian randomization. We also perform in silico functional analysis by integrating with other types of omics data. RESULTS: We identified 10 loci, including 8 novel, capturing 30% of the heritability of the protein. We detected that plasma ACE2 was genetically correlated with vascular diseases, severe COVID-19, and a wide range of human complex diseases and medications. An X-chromosome cis-protein quantitative trait loci-based mendelian randomization analysis suggested a causal effect of elevated ACE2 levels on COVID-19 severity (odds ratio, 1.63 [95% CI, 1.10-2.42]; P=0.01), hospitalization (odds ratio, 1.52 [95% CI, 1.05-2.21]; P=0.03), and infection (odds ratio, 1.60 [95% CI, 1.08-2.37]; P=0.02). Tissue- and cell type-specific transcriptomic and epigenomic analysis revealed that the ACE2 regulatory variants were enriched for DNA methylation sites in blood immune cells. CONCLUSIONS: Human plasma ACE2 shares a genetic basis with cardiovascular disease, COVID-19, and other related diseases. The genetic architecture of the ACE2 protein is mapped, providing a useful resource for further biological and clinical studies on this coronavirus receptor.
Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Enzima de Conversão de Angiotensina 2/genética , COVID-19/genética , Estudos Transversais , Estudo de Associação Genômica Ampla , Humanos , Receptores de Coronavírus , SARS-CoV-2RESUMO
Multipath in 3D imaging happens when one pixel receives light from multiple reflections, which causes errors in the measured point cloud. In this paper, we propose the soft epipolar 3D(SEpi-3D) method to eliminate multipath in temporal space with an event camera and a laser projector. Specifically, we align the projector and event camera row onto the same epipolar plane with stereo rectification; we capture event flow synchronized with the projector frame to construct a mapping relationship between event timestamp and projector pixel; we develop a multipath eliminating method that utilizes the temporal information from the event data together with the epipolar geometry. Experiments show that the RMSE decreases by 6.55mm on average in the tested multipath scenes, and the percentage of error points decreases by 7.04%.
RESUMO
Crucial to variety improvement programs is the reliable and accurate prediction of genotype's performance across environments. However, due to the impactful presence of genotype by environment (G×E) interaction that dictates how changes in expression and function of genes influence target traits in different environments, prediction performance of genomic selection (GS) using single-environment models often falls short. Furthermore, despite the successes of genome-wide association studies (GWAS), the genetic insights derived from genome-to-phenome mapping have not yet been incorporated in predictive analytics, making GS models that use Gaussian kernel primarily an estimator of genomic similarity, instead of the underlying genetics characteristics of the populations. Here, we developed a GS framework that, in addition to capturing the overall genomic relationship, can capitalize on the signal of genetic associations of the phenotypic variation as well as the genetic characteristics of the populations. The capacity of predicting the performance of populations across environments was demonstrated by an overall gain in predictability up to 31% for the winter wheat DH population. Compared to Gaussian kernels, we showed that our multi-environment weighted kernels could better leverage the significance of genetic associations and yielded a marked improvement of 4-33% in prediction accuracy for half-sib families. Furthermore, the flexibility incorporated in our Bayesian implementation provides the generalizable capacity required for predicting multiple highly genetic heterogeneous populations across environments, allowing reliable GS for genetic improvement programs that have no access to genetically uniform material.
Assuntos
Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Humanos , Teorema de Bayes , Fenótipo , Genômica , Modelos Genéticos , Seleção Genética , Genótipo , Genoma de PlantaRESUMO
Kidney disease can be caused by various internal and external factors that have led to a continual increase in global deaths. Current treatment methods can alleviate but do not markedly prevent disease development. Further research on kidney disease has revealed the crucial function of epigenetics, especially acetylation, in the pathology and physiology of the kidney. Histone acetyltransferases (HATs), histone deacetylases (HDACs), and acetyllysine readers jointly regulate acetylation, thus affecting kidney physiological homoeostasis. Recent studies have shown that acetylation improves mechanisms and pathways involved in various types of nephropathy. The discovery and application of novel inhibitors and activators have further confirmed the important role of acetylation. In this review, we provide insights into the physiological process of acetylation and summarise its specific mechanisms and potential therapeutic effects on renal pathology.
Assuntos
Nefropatias , Humanos , Acetilação , Nefropatias/tratamento farmacológico , Rim , Epigênese Genética , EpigenômicaRESUMO
The novel biomarker, insulin-like growth factor binding protein 7 (IGFBP7), is used clinically to predict different types of acute kidney injury (AKI) and has drawn significant attention as a urinary biomarker. However, as a secreted protein in the circulation of patients with AKI, it is unclear whether IGFBP7 acts as a key regulator in AKI progression, and if mechanisms underlying its upregulation still need to be determined. Here we found that IGFBP7 is highly expressed in the blood and urine of patients and mice with AKI, possibly via a c-Jun-dependent mechanism, and is positively correlated with kidney dysfunction. Global knockout of IGFBP7 ameliorated kidney dysfunction, inflammatory responses, and programmed cell death in murine models of cisplatin-, kidney ischemia/reperfusion-, and lipopolysaccharide-induced AKI. IGFBP7 mainly originated from kidney tubular epithelial cells. Conditional knockout of IGFBP7 from the kidney protected against AKI. By contrast, rescue of IGFBP7 expression in IGFBP7-knockout mice restored kidney damage and inflammation. IGFBP7 function was determined in vitro using recombinant IGFBP7 protein, IGFBP7 knockdown, or overexpression. Additionally, IGFBP7 was found to bind to poly [ADP-ribose] polymerase 1 (PARP1) and inhibit its degradation by antagonizing the E3 ubiquitin ligase ring finger protein 4 (RNF4). Thus, IGFBP7 in circulation acts as a biomarker and key mediator of AKI by inhibiting RNF4/PARP1-mediated tubular injury and inflammation. Hence, over-activation of the IGFBP7/PARP1 axis represents a promising target for AKI treatment.
Assuntos
Injúria Renal Aguda , Inibidor Tecidual de Metaloproteinase-2 , Adenosina Difosfato Ribose , Animais , Biomarcadores , Cisplatino/toxicidade , Inflamação , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Lipopolissacarídeos , Camundongos , Camundongos Knockout , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Postharvest deterioration is among the major challenges for the fruit industry. Regulation of the fruit softening rate is an effective strategy for extending shelf-life and reducing the economic losses due postharvest deterioration. The tomato myoinositol monophosphatase 3 gene SlIMP3, which showed highest expression level in fruit, was expressed and purified. SlIMP3 demonstrated high affinity with the L-Gal 1-P and D-Ins 3-P, and acted as a bifunctional enzyme in the biosynthesis of AsA and myoinositol. Overexpression of SlIMP3 not only improved AsA and myoinositol content, but also increased cell wall thickness, improved fruit firmness, delayed fruit softening, decreased water loss, and extended shelf-life. Overexpression of SlIMP3 also increased uronic acid, rhamnose, xylose, mannose, and galactose content in cell wall of fruit. Treating fruit with myoinositol obtained similar fruit phenotypes of SlIMP3-overexpressed fruit, with increased cell wall thickness and delayed fruit softening. Meanwhile, overexpression of SlIMP3 conferred tomato fruit tolerance to Botrytis cinerea. The function of SlIMP3 in cell wall biogenesis and fruit softening were also verified using another tomato species, Ailsa Craig (AC). Overexpression of SlDHAR in fruit increased AsA content, but did not affect the cell wall thickness or fruit firmness and softening. The results support a critical role for SlIMP3 in AsA biosynthesis and cell wall biogenesis, and provide a new method of delaying tomato fruit softening, and insight into the link between AsA and cell wall metabolism.
Assuntos
Solanum lycopersicum , Ácido Ascórbico , Parede Celular/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Inositol/metabolismo , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
This paper presents a calibration method for a microscopic structured light system with an extended depth of field (DOF). We first employed the focal sweep technique to achieve large enough depth measurement range, and then developed a computational framework to alleviate the impact of phase errors caused by the standard off-the-shelf calibration target (black circles with a white background). Specifically, we developed a polynomial interpolation algorithm to correct phase errors near the black circles to obtain more accurate phase maps for projector feature points determination. Experimental results indicate that the proposed method can achieve a measurement accuracy of approximately 1.0 µm for a measurement volume of approximately 2,500 µm (W) × 2,000 µm (H) × 500 µm (D).
RESUMO
A base-catalyzed divergent synthesis of multisubstituted imidazoles through TosMIC-based [3 + 2] cyclization reaction has been developed. In the presence of ketenimines and tBuONa, 1,4,5-trisubstituted imidazoles were obtained. Nonetheless, in the absence of ketenimines, 1,4-disubstituted imidazole was produced through cyclodimerization of TosMIC.
Assuntos
Cianetos , Imidazóis , Ciclização , CatáliseRESUMO
OBJECTIVE: To investigate the effect and mechanism of Buyang Huanwu decoction (BYHWD) on angiogenesis of rat brain microvascular endothelial cells (RBMECs) after oxygen-glucose deprivation reperfusion (OGD/R) injury. METHODS: RBMECs were pretreated with BYHWD containing serum 24â h before OGD/R injury was induced. Cells were randomly divided into blank control group, model control group, BYHWD group (provided BYHWD containing serum) and LY294002 group [treated with phosphoinositide 3-kinase (PI3K) inhibitor LY294002 for 1â h before provided BYHWD containing serum]. The cell viability, migration and tube formation abilities of RBMECs were detected by CCK-8, scratch wound healing, Transwell migration and tube formation assays, respectively. The protein expression levels of PI3K, p-PI3K, protein kinase B (AKT), p-AKT, hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) were determined by Western blotting. RESULTS: Compared with model control group, cell viability, migration and tube formation abilities of RBMECs were significantly improved in BYHWD group (all P<0.01), the protein expression levels of p-PI3K, p-AKT, HIF-1α and VEGF were up-regulated (all P<0.05); while above effects were blocked by LY294002. CONCLUSION: BYHWD can promote angiogenesis of RBMECs after OGD/R injury, which may be related to the increased protein expression of HIF-1α and VEGF through activation of PI3K-AKT signaling pathway.
Assuntos
Fosfatidilinositol 3-Quinase , Traumatismo por Reperfusão , Ratos , Animais , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Oxigênio/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Transdução de Sinais , Encéfalo/metabolismoRESUMO
Unicellular and multicellular tomato trichomes function as mechanical and chemical barriers against herbivores. Auxin treatment increased the formation of II, V and VI type trichomes in tomato leaves. The auxin response factor gene SlARF4, which was highly expressed in II, V and VI type trichomes, positively regulated the auxin-induced formation of II, V and VI type trichomes in the tomato leaves. SlARF4 overexpression plants with high densities of these trichomes exhibited tolerance to spider mites. Two R2R3 MYB genes, SlTHM1 and SlMYB52, were directly targeted and inhibited by SlARF4. SlTHM1 was specifically expressed in II and VI type trichomes and negatively regulated the auxin-induced formation of II and VI type trichomes in the tomato leaves. SlTHM1 down-regulation plants with high densities of II and VI type trichomes also showed tolerance to spider mites. SlMYB52 was specifically expressed in V type trichomes and negatively regulated the auxin-induced formation of V type trichome in the tomato leaves. The regulation of SlARF4 on the formation of II, V and VI type trichomes depended on SlTHM1 and SlMYB52, which directly targeted cyclin gene SlCycB2 and increased its expression. In conclusion, our data indicates that the R2R3 MYB-dependent auxin signalling pathway regulates the formation of II, V and VI type trichomes in tomato leaves. Our study provides an effective method for improving the tolerance of tomato to spider mites.
Assuntos
Solanum lycopersicum , Tetranychidae , Animais , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos , Solanum lycopersicum/genética , Folhas de Planta/genética , Tetranychidae/genética , TricomasRESUMO
Tomato (Solanum lycopersicum) fruit ripening is accompanied by the degradation of chlorophylls and the accumulation of carotenoids and flavonoids. Tomato SlMYB72 belongs to the R2R3 MYB subfamily, is located in the nucleus, and possesses transcriptional activator activity. Down-regulation of the SlMYB72 gene produced uneven-colored fruits; that is, dark green spots appeared on immature and mature green fruits, whereas yellow spots appeared on red fruits. Down-regulation of SlMYB72 increased chlorophyll accumulation, chloroplast biogenesis and development, and photosynthesis rate in fruits. This down-regulation decreased lycopene content, promoted ß-carotene production and chromoplast development, and increased flavonoid accumulation in fruits. RNA sequencing analysis revealed that down-regulation of SlMYB72 altered the expression levels of genes involved in the biosynthesis of chlorophylls, carotenoids, and flavonoids. SlMYB72 protein interacted with the auxin response factor SlARF4. SlMYB72 directly targeted protochlorophyllide reductase, Mg-chelatase H subunit, and knotted1-like homeobox2 genes and regulated chlorophyll biosynthesis and chloroplast development. SlMYB72 directly bound to phytoene synthase, ζ-carotene isomerase, and lycopene ß-cyclase genes and regulated carotenoid biosynthesis. SlMYB72 directly targeted 4-coumarate-coenzyme A ligase and chalcone synthase genes and regulated the biosynthesis of flavonoids and phenolic acid. The uneven color phenotype in RNA interference-SlMYB72 fruits was due to uneven silencing of SlMYB72 and uneven expression of chlorophyll, carotenoid, and flavonoid biosynthesis genes. In summary, this study identified important roles for SlMYB72 in the regulation of chlorophyll, carotenoid, and flavonoid metabolism and provided a potential target to improve fruit nutrition in horticultural crops.
Assuntos
Carotenoides/metabolismo , Clorofila/genética , Clorofila/metabolismo , Flavonoides/genética , Frutas/genética , Frutas/metabolismo , Solanum lycopersicum/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Solanum lycopersicum/metabolismoRESUMO
Tomato trichomes act as a mechanical and chemical barrier against pests. An R2R3 MYB transcription factor gene, SlMYB75, is highly expressed in type II, V, and VI trichomes. SlMYB75 protein is located in the nucleus and possesses transcriptional activation activity. Down-regulation of SlMYB75 increased the formation of type II, V, and VI trichomes, accumulation of δ-elemene, ß-caryophyllene, and α-humulene in glandular trichomes, and tolerance to spider mites in tomato. In contrast, overexpression of SlMYB75 inhibited trichome formation and sesquiterpene accumulation, and increased plant sensitivity to spider mites. RNA-Seq analyses of the SlMYB75 RNAi line indicated massive perturbation of the transcriptome, with a significant impact on several classes of transcription factors. Expression of the MYB genes SlMYB52 and SlTHM1 was strongly reduced in the RNAi line and increased in the SlMYB75-overexpressing line. SlMYB75 protein interacted with SlMYB52 and SlTHM1 and activated their expression. SlMYB75 directly targeted the promoter of the cyclin gene SlCycB2, increasing its activity. The auxin response factor SlARF4 directly targeted the promoter of SlMYB75 and inhibited its expression. SlMYB75 also bound to the promoters of the terpene synthase genes SlTPS12, SlTPS31, and SlTPS35, inhibiting their transcription. Our findings indicate that SlMYB75 perturbation affects several transcriptional circuits, resulting in altered trichome density and metabolic content.
Assuntos
Proteínas de Plantas , Sesquiterpenos/metabolismo , Solanum lycopersicum , Fatores de Transcrição , Tricomas/crescimento & desenvolvimento , Animais , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Alcohol consumption is one of the risk factors for kidney injury. The underlying mechanism of alcohol-induced kidney injury remains largely unknown. We previously found that the kidney in a mouse model of alcoholic kidney injury had severe inflammation. In this study, we found that the administration of alcohol was associated with the activation of NLRP3 inflammasomes and NF-κB signaling, and the production of pro-inflammatory cytokines. Whole-genome methylation sequencing (WGBS) showed that the DNA encoding fat mass and obesity-associated protein (FTO) was significantly methylated in the alcoholic kidney. This finding was confirmed with the bisulfite sequencing (BSP), which showed that alcohol increased DNA methylation of FTO in the kidney. Furthermore, inhibition of DNA methyltransferases (DNMTs) by 5-azacytidine (5-aza) reversed alcohol-induced kidney injury and decreased the mRNA and protein levels of FTO. Importantly, we found that FTO, the m6A demethylase, epigenetically modified peroxisome proliferator activated receptor-α (PPAR-α) in a YTH domain family 2 (YTHDF2)-dependent manner, which resulted in inflammation in alcoholic kidney injury models. In conclusion, our findings indicate that alcohol increases the methylation of PPAR-α m6A by FTO-mediated YTHDF2 epigenetic modification, which ultimately leads to the activation of NLRP3 inflammasomes and NF-κB-driven renal inflammation in the kidney. These findings may provide novel strategies for preventing and treating alcoholic kidney diseases.