RESUMO
Potassium (K) fertilisation has frequently been shown to enhance plant resistance against pathogens, though the mechanisms remain elusive. This study investigates the interaction dynamics between Nicotiana benthamiana and the pathogen Alternaria longipes under different planta K levels. On the host side, adding K activated the expressions of three NLR (nucleotide-binding domain and leucine-rich repeat-containing proteins) resistance genes, including NbRPM1, NbR1B23 and NbNBS12. Silencing these NLRs attenuated resistance in high-K (HK, 40.8 g/kg) plant, whereas their overexpression strengthened resistance in low-K (LK, 23.9 g/kg) plant. Typically, these NLRs mainly strengthened plant resistance via promoting the expression of pathogenesis-related genes (PRs), ROS burst and synthesis of antifungal metabolites in HK plant. On the pathogen side, the expression of effectors HKCSP1, HKCSP2 and LKCSP were shown to be related to planta K content. A. longipes mainly expressed effectors HKCSP1 and HKCSP2 in HK plant to interfere host resistance. HKCSP1 physically interacted with NbRPM1 to promote the degradation of NbRPM1, then attenuated related resistance in HK N. benthamiana. Meanwhile, HKCSP2 directly interacted with NbPR5 to suppress resistance in HK plant. In LK plant, A. longipes mainly deployed LKCSP that interacted with NbR1B23 to interfere reduce resistance in N. benthamiana. Overall, our research insights that both pathogen and host mobilise distinct strategies to outcompete each other during interactions in different K nutrient environments.
Assuntos
Alternaria , Nicotiana , Doenças das Plantas , Proteínas de Plantas , Potássio , Nicotiana/microbiologia , Nicotiana/genética , Nicotiana/metabolismo , Alternaria/fisiologia , Doenças das Plantas/microbiologia , Potássio/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Proteínas NLR/metabolismo , Proteínas NLR/genéticaRESUMO
The role of lncRNA and circRNA in wheat grain development is still unclear. The objectives of this study were to characterize the lncRNA and circRNA in the wheat grain development and to construct the interaction network among lncRNA, circRNA, and their target miRNA to propose a lncRNA-circRNA-miRNA module related to wheat grain development. Full transcriptome sequencing on two wheat varieties (Annong 0942 and Anke 2005) with significant differences in 1000-grain weight at 10 d (days after pollination), 20 d, and 30 d of grain development were conducted. We detected 650, 736, and 609 differentially expressed lncRNA genes, and 769, 1054, and 1062 differentially expressed circRNA genes in the grains of 10 days, 20 days and 30 days after pollination between Annong 0942 and Anke 2005, respectively. An analysis of the lncRNA-miRNA and circRNA-miRNA targeting networks reveals that circRNAs exhibit a more complex and extensive interaction network in the development of cereal grains and the formation of grain shape. Central to these interactions are tae-miR1177, tae-miR1128, and tae-miR1130b-3p. In contrast, lncRNA genes only form a singular network centered around tae-miR1133 and tae-miR5175-5p when comparing between varieties. Further analysis is conducted on the underlying genes of all target miRNAs, we identified TaNF-YB1 targeted by tae-miR1122a and TaTGW-7B targeted by miR1130a as two pivotal regulatory genes in the development of wheat grains. The quantitative real-time PCR (qRT-PCR) and dual-luciferase reporter assays confirmed the target regulatory relationships between miR1130a-TaTGW-7B and miR1122a-TaNF-YB1. We propose a network of circRNA and miRNA-mediated gene regulation in the development of wheat grains.
Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , MicroRNAs , RNA Circular , RNA Longo não Codificante , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , RNA Longo não Codificante/genética , RNA Circular/genética , RNA Circular/metabolismo , MicroRNAs/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Redes Reguladoras de Genes , RNA de Plantas/genética , Perfilação da Expressão GênicaRESUMO
Black wolfberry (Lycium ruthenicum Murr.) contains various bioactive metabolites represented by flavonoids, which are quite different among production regions. However, the underlying regulation mechanism of flavonoid biosynthesis governing the bioactivity of black wolfberry remains unclear. Presently, we compared the bioactivity of black wolfberry from five production regions. Multi-omics were performed to construct the regulation network associated with the fruit bioactivity. The detailed regulation mechanisms were identified using genetic and molecular methods. Typically, Qinghai (QH) fruit exhibited higher antioxidant and anti-inflammatory activities. The higher medicinal activity of QH fruit was closely associated with the accumulation of eight flavonoids, especially Kaempferol-3-O-rutinoside (K3R) and Quercetin-3-O-rutinoside (rutin). Flavonoid biosynthesis was found to be more active in QH fruit, and the upregulation of LrFLS, LrCHS, LrF3H and LrCYP75B1 caused the accumulation of K3R and rutin, leading to high medicinal bioactivities of black wolfberry. Importantly, transcription factor LrMYB94 was found to regulate LrFLS, LrCHS and LrF3H, while LrWRKY32 directly triggered LrCYP75B1 expression. Moreover, LrMYB94 interacted with LrWRKY32 to promote LrWRKY32-regulated LrCYP75B1 expression and rutin synthesis in black wolfberry. Transgenic black wolfberry overexpressing LrMYB94/LrWRKY32 contained higher levels of K3R and rutin, and exhibited high medicinal bioactivities. Importantly, the LrMYB94/LrWRKY32-regulated flavonoid biosynthesis was light-responsive, showing the importance of light intensity for the medicinal quality of black wolfberry. Overall, our results elucidated the regulation mechanisms of K3R and rutin synthesis, providing the basis for the genetic breeding of high-quality black wolfberry.
Assuntos
Lycium , Lycium/genética , Melhoramento Vegetal , Flavonoides , Antioxidantes , Rutina , Frutas/genéticaRESUMO
An essential step in the application of near infrared spectroscopy technology is the spectrum preprocessing. A reasonable implementation of it ensures that the effective spectral information is correctly extracted and, also that the model's accuracy is increased. However, some analysts' research still uses the manual approach of trial and error, particularly those less skilled ones. Previous papers have provided preprocessing optimization algorithms for NIR, but there are still some problems that need to be resolved, such as the unwieldy sequence determination of preprocessing method or, the fluctuated optimization outcomes or, lack of sufficient statistical information. This research suggests a spectrum auto-analysis methodology named self-expansion full information optimization strategy, a new powerful open-source technique for concurrently addressing all of these above issues simultaneously. For the first time in the field of chemometrics, this algorithm offers a reliable and effective automatic near infrared auto-modelling method based on the statistical informatics. With the aid of its built-in modules, such as information generators, spectrum processors, etc., it is able to fully search the common preprocessing techniques, which is determined by Monte Carlo cross validation. Then the final ensemble calibration model is built by employing the optimized preprocessing schemes, along with the wavelength variables screening algorithm. The optimization strategy can offer the user objective useful statistics information created throughout the modeling process to further examine the model's effectiveness. The results demonstrate that the suggested method can easily and successfully extract spectrum information and develop calibration models by putting it to the test on two groups of actual near-infrared spectral data. Additionally, this optimization strategy can also be applied to other spectrum analysis areas, such Raman spectroscopy or infrared spectroscopy, by changing a few of its parameters, and has extraordinary application value.
RESUMO
Cytospora canker, caused by Cytospora mali, is the most destructive disease in production of apples (Malus domestica). Adding potassium (K) to apple trees can effectively control this disease. However, the underlying mechanisms of apple resistance to C. mali under high-K (HK) status remain unknown. Here, we found that HK (9.30 g/kg) apple tissues exhibited high disease resistance. The resistance was impeded when blocking K channels, leading to susceptibility even under HK conditions. We detected a suite of resistance events in HK apple tissues, including upregulation of resistance genes, callose deposition, and formation of ligno-suberized tissues. Further multiomics revealed that the phenylpropanoid pathway was reprogrammed by increasing K content from low-K (LK, 4.30 g/kg) status, leading to increases of 18 antifungal chemicals. Among them, the physiological concentration of coumarin (1,2-benzopyrone) became sufficient to inhibit C. mali growth in HK tissues, and exogenous application could improve the C. mali resistance of LK apple branches. Transgenic apple calli overexpressing beta-glucosidase 40 (MdBGLU40), which encodes the enzyme for coumarin synthesis, contained higher levels of coumarin and exhibited high resistance to C. mali even under LK conditions. Conversely, the suppression of MdBGLU40 through RNAi reduced coumarin content and resistance in HK apple calli, supporting the importance of coumarin accumulation in vivo for apple resistance. Moreover, we found that the upregulation of transcription factor MdMYB1r1 directly activated MdBGLU40 and the binding affinity of MdMYB1r1 to the MdBGLU40 promoter increased in HK apple tissue, leading to high levels of coumarin and resistance in HK apple. Overall, we found that the accumulation of defensive metabolites strengthened resistance in apple when raising K from insufficient to optimal status, and these results highlight the optimization of K content in fertilization practices as a disease management strategy.
Assuntos
Ascomicetos , Malus , Malus/metabolismo , Ascomicetos/genética , Potássio/metabolismo , Cumarínicos/metabolismoRESUMO
OBJECTIVE: To study the prevalence of mild cognitive impairment (MCI) in the urban and the rural areas in Chengdu, Southwest China. METHODS: Residents aged 55 or over were selected by stratified random cluster sampling from 19 districts, cities, and counties of Chengdu area in Sichuan province. A two-stage survey was carried out. In the first stage, CMMSE, CES-D were used as screening instruments. In the second stage, Diagnostic questionnaires of dementia and CDR were used as diagnostic instruments. The diagnostic criteria of mild cognitive impairment adopted from Petersen's were: (1) memory complaint; (2) normal activities of daily living; (3) normal general cognitive function; (4) memory impairment incompatible with age; (5) not demented; (6) CDR = 0.5 and (7) exclusion of the reversible cognitive impairment caused by other factors (i.e. depression). RESULTS: Three thousand, nine hundred and ten subjects were examined. The prevalence rates of MCI was 2.4%. The MCI prevalence rates in the urban and the rural areas were 1.5%, 2.5% respectively, without significant difference. The MCI prevalence in males and females were 1.8%, 2.9% respectively. Prevalence rate in female was higher than in males with significant difference. Prevalence of illiteracy (4.0%) was the highest among different educational levels. The accumulated prevalence increased with age. CONCLUSION: The prevalence of MCI (2.4%) was slightly higher than the prevalence of AD (2.05%) in the same areas of Chengdu. MCI seemed to be a high risk factor for AD which should to be followed up. Early intervention in MCI might be helpful in the prevention of AD.