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1.
Plant Biotechnol J ; 22(3): 751-758, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37932934

RESUMO

Heading date (or flowering time) is a key agronomic trait that affects seasonal and regional adaption of rice cultivars. An unoptimized heading date can either not achieve a high yield or has a high risk of encountering abiotic stresses. There is a strong demand on the mild to moderate adjusting the heading date in breeding practice. Genome editing is a promising method which allows more precise and faster changing the heading date of rice. However, direct knock out of major genes involved in regulating heading date will not always achieve a new germplasm with expected heading date. It is still challenging to quantitatively adjust the heading date of elite cultivars with best adaption for broader region. In this study, we used a CRISPR-Cas9 based genome editing strategy called high-efficiency multiplex promoter-targeting (HMP) to generate novel alleles at cis-regulatory regions of three major heading date genes: Hd1, Ghd7 and DTH8. We achieved a series of germplasm with quantitative variations of heading date by editing promoter regions and adjusting the expression levels of these genes. We performed field trials to screen for the best adapted lines for different regions. We successfully expanded an elite cultivar Ningjing8 (NJ8) to a higher latitude region by selecting a line with a mild early heading phenotype that escaped from cold stress and achieved high yield potential. Our study demonstrates that HMP is a powerful tool for quantitatively regulating rice heading date and expanding elite cultivars to broader regions.


Assuntos
Oryza , Oryza/metabolismo , Locos de Características Quantitativas , Sistemas CRISPR-Cas/genética , Melhoramento Vegetal , Regiões Promotoras Genéticas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética
2.
BMC Pediatr ; 23(1): 642, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114939

RESUMO

BACKGROUND: The aim of this study was to find early predictors of Intravenous Immunoglobulin (IVIG)-Resistant Kawasaki Disease. METHODS: Patients diagnosed with Kawasaki disease were enrolled in this study. Univariate analysis and multiple logistic regression were used to analyze the clinical characteristics and laboratory findings of patients in both groups before IVIG treatment. Independent predictors of Intravenous Immunoglobulin-Resistant Kawasaki Disease were analyzed, and a prediction model for children with Intravenous Immunoglobulin-Resistant Kawasaki Disease was constructed. RESULTS: A total of 108 children (67 males and 41 females) with IVIG-sensitive Kawasaki disease and 31 children (20 males and 11 females) with IVIG-resistant Kawasaki disease participated in this study. Compared with the IVIG-sensitive group, the duration of hospitalization, ALT, AST, GLB, r-GT, IgG, PCT, and ESR was elevated in the IVIG-resistant KD group, and ATG16L1, LC3II, BECN1, RBC, HGB, ALB, A/G, and CK were significantly lower (P < 0.05). mRNA expression of ESR, BECN1, and LC3II were independent risk factors for IVIG-resistant Kawasaki disease. A logistic regression model and scoring system were established, and the cut-off values of independent risk factors were derived from ROC curves: ESR ≥ 79.5 mm/h, BECN1 ≤ 0.645, LC3II ≤ 0.481. A new scoring system was established according to the respective regression coefficients as follows: ESR ≥ 79.5 mm/h (1 point), BECN1 ≤ 0.645 (1 point). LC3II ≤ 0.481 (2 points), 0-1 as low risk for IVIG non-response, and ≥ 2 as high risk. Applied to this group of study subjects, the sensitivity was 87.10%, specificity 83.33%, Youden index 0.70, AUC 0.9. CONCLUSIONS: Autophagy markers ATG16L1, BECN1, and LC3II are down-regulated in the expression of IVIG -resistant KD. ESR, BECN1, and LC3II mRNAs are independent risk factors for IVIG-resistant KD and may be involved in the development of IVIG-resistant KD. This study established a new model that can be used to predict IVIG-resistant KD, and future validation in a larger population is needed.


Assuntos
Imunoglobulinas Intravenosas , Síndrome de Linfonodos Mucocutâneos , Criança , Masculino , Feminino , Humanos , Lactente , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Modelos Logísticos , Fatores de Risco , Curva ROC , Estudos Retrospectivos
3.
Plants (Basel) ; 12(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37960079

RESUMO

Salt is harmful to crop production. Therefore, it is important to understand the mechanism of salt tolerance in rice. CIPK genes have various functions, including regulating salt tolerance and other types of stress and nitrogen use efficiency. In rice, OsCIPK24 is known to regulate salt tolerance, but other OsCIPKs could also function in salt tolerance. In this study, we identified another OsCIPK-OsCIPK9-that can regulate salt tolerance. Knockout of OsCIPK9 in rice could improve salt tolerance. Through expression analyses, OsCIPK9 was found to be mainly expressed in the roots and less expressed in mature leaves. Meanwhile, OsCIPK9 had the highest expression 6 h after salt treatment. In addition, we proved the interaction between OsCIPK9 and OsSOS3. The RNA-seq data showed that OsCIPK9 strongly responded to salt treatment, and the transporters related to salt tolerance may be downstream genes of OsCIPK9. Finally, haplotype analyses revealed that Hap6 and Hap8 mainly exist in indica, potentially providing a higher salt tolerance. Overall, a negative regulator of salt tolerance, OsCIPK9, which interacted with OsSOS3 similarly to OsCIPK24 and influenced salt-related transporters, was identified, and editing OsCIPK9 potentially could be helpful for breeding salt-tolerant rice.

4.
Plants (Basel) ; 12(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836098

RESUMO

Rice is a crucial global food crop, but it lacks a natural tolerance to high salt levels, resulting in significant yield reductions. To gain a comprehensive understanding of the molecular mechanisms underlying rice's salt tolerance, further research is required. In this study, the transcriptomic and metabolomic differences between the salt-tolerant rice variety Lianjian5 (TLJIAN) and the salt-sensitive rice variety Huajing5 (HJING) were examined. Transcriptome analysis revealed 1518 differentially expressed genes (DEGs), including 46 previously reported salt-tolerance-related genes. Notably, most of the differentially expressed transcription factors, such as NAC, WRKY, MYB, and EREBP, were upregulated in the salt-tolerant rice. Metabolome analysis identified 42 differentially accumulated metabolites (DAMs) that were upregulated in TLJIAN, including flavonoids, pyrocatechol, lignans, lipids, and trehalose-6-phosphate, whereas the majority of organic acids were downregulated in TLJIAN. The interaction network of 29 differentially expressed transporter genes and 19 upregulated metabolites showed a positive correlation between the upregulated calcium/cation exchange protein genes (OsCCX2 and CCX5_Ath) and ABC transporter gene AB2E_Ath with multiple upregulated DAMs in the salt-tolerant rice variety. Similarly, in the interaction network of differentially expressed transcription factors and 19 upregulated metabolites in TLJIAN, 6 NACs, 13 AP2/ERFs, and the upregulated WRKY transcription factors were positively correlated with 3 flavonoids, 3 lignans, and the lipid oleamide. These results suggested that the combined effects of differentially expressed transcription factors, transporter genes, and DAMs contribute to the enhancement of salt tolerance in TLJIAN. Moreover, this study provides a valuable gene-metabolite network reference for understanding the salt tolerance mechanism in rice.

5.
Plants (Basel) ; 12(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37765407

RESUMO

Rice yield and grain quality are highly sensitive to salinity stress. Salt-tolerant/susceptible rice cultivars respond to salinity differently. To explore the variation in grain yield and quality to moderate/severe salinity stress, five rice cultivars differing in degrees of salt tolerance, including three salt-tolerant rice cultivars (Lianjian 5, Lianjian 6, and Lianjian 7) and two salt-susceptible rice cultivars (Wuyunjing 30 and Lianjing 7) were examined. Grain yield was significantly decreased under salinity stress, while the extent of yield loss was lesser in salt-tolerant rice cultivars due to the relatively higher grain filling ratio and grain weight. The milling quality continued to increase with increasing levels. There were genotypic differences in the responses of appearance quality to mild salinity. The appearance quality was first increased and then decreased with increasing levels of salinity stress in salt-tolerant rice but continued to decrease in salt-susceptible rice. Under severe salinity stress, the protein accumulation was increased and the starch content was decreased; the content of short branched-chain of amylopectin was decreased; the crystallinity and stability of the starch were increased, and the gelatinization temperature was increased. These changes resulted in the deterioration of cooking and eating quality of rice under severe salinity-stressed environments. However, salt-tolerant and salt-susceptible rice cultivars responded differently to moderate salinity stress in cooking and eating quality and in the physicochemical properties of the starch. For salt-tolerant rice cultivars, the chain length of amylopectin was decreased, the degrees of order of the starch structure were decreased, and pasting properties and thermal properties were increased significantly, whereas for salt-susceptible rice cultivars, cooking and eating quality was deteriorated under moderate salinity stress. In conclusion, the selection of salt-tolerant rice cultivars can effectively maintain the rice production at a relatively high level while simultaneously enhancing grain quality in moderate salinity-stressed environments. Our results demonstrate specific salinity responses among the rice genotypes and the planting of salt-tolerant rice under moderate soil salinity is a solution to ensure rice production in China.

6.
Nat Commun ; 14(1): 3550, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321989

RESUMO

Salinity stress progressively reduces plant growth and productivity, while plant has developed complex signaling pathways to confront salt stress. However, only a few genetic variants have been identified to mediate salt tolerance in the major crop rice, and the molecular mechanism remains poorly understood. Here, we identify ten candidate genes associated with salt-tolerance (ST) traits by performing a genome-wide association analysis in rice landraces. We characterize two ST-related genes, encoding transcriptional factor OsWRKY53 and Mitogen-activated protein Kinase Kinase OsMKK10.2, that mediate root Na+ flux and Na+ homeostasis. We further find that OsWRKY53 acts as a negative modulator regulating expression of OsMKK10.2 in promoting ion homeostasis. Furthermore, OsWRKY53 trans-represses OsHKT1;5 (high-affinity K+ transporter 1;5), encoding a sodium transport protein in roots. We show that the OsWRKY53-OsMKK10.2 and OsWRKY53-OsHKT1;5 module coordinate defenses against ionic stress. The results shed light on the regulatory mechanisms underlying plant salt tolerance.


Assuntos
Oryza , Tolerância ao Sal , Tolerância ao Sal/genética , Oryza/metabolismo , Estudo de Associação Genômica Ampla , Estresse Salino/genética , Transporte de Íons , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Front Neurol ; 14: 1156879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37153682

RESUMO

Ischemic stroke is by far the most common cerebrovascular disease and a major burden to the global economy and public health. Trimethylamine-N-oxide (TMAO), a small molecule compound produced by the metabolism of intestinal microorganisms, is reportedly associated with the risk of stroke, as well as the severity and prognosis of stroke; however, this conclusion remains contentious. This article reviews the production of TMAO, TMAO's relationship with different etiological types of ischemic stroke, and the possibility of reducing TMAO levels to improve the prognosis of ischemic stroke.

9.
Entropy (Basel) ; 24(11)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36421512

RESUMO

Underwater acoustic target recognition is very complex due to the lack of labeled data sets, the complexity of the marine environment, and the interference of background noise. In order to enhance it, we propose an attention-based residual network recognition method (AResnet). The method can be used to identify ship-radiated noise in different environments. Firstly, a residual network is used to extract the deep abstract features of three-dimensional fusion features, and then a channel attention module is used to enhance different channels. Finally, the features are classified by the joint supervision of cross-entropy and central loss functions. At the same time, for the recognition of ship-radiated noise in other environments, we use the pre-training network AResnet to extract the deep acoustic features and apply the network structure to underwater acoustic target recognition after fine-tuning. The two sets of ship radiation noise datasets are verified, the DeepShip dataset is trained and verified, and the average recognition accuracy is 99%. Then, the trained AResnet structure is fine-tuned and applied to the ShipsEar dataset. The average recognition accuracy is 98%, which is better than the comparison method.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35969542

RESUMO

As machine learning algorithms are increasingly deployed for high-impact automated decision-making, the presence of bias (in datasets or tasks) gradually becomes one of the most critical challenges in machine learning applications. Such challenges range from the bias of race in face recognition to the bias of gender in hiring systems, where race and gender can be denoted as sensitive attributes. In recent years, much progress has been made in ensuring fairness and reducing bias in standard machine learning settings. Among them, learning fair representations with respect to the sensitive attributes has attracted increasing attention due to its flexibility in learning the rich representations based on advances in deep learning. In this article, we propose graph-fair, an algorithmic approach to learning fair representations under the graph Laplacian regularization, which reduces the separation between groups and the clustering within a group by encoding the sensitive attribute information into the graph. We have theoretically proved the underlying connection between graph regularization and distance correlation and show that the latter can be regarded as a standardized version of the former, with an additional advantage of being scale-invariant. Therefore, we naturally adopt the distance correlation as the fairness constraint to decrease the dependence between sensitive attributes and latent representations, called dist-fair. In contrast to existing approaches using measures of dependency and adversarial generators, both graph-fair and dist-fair provide simple fairness constraints, which eliminate the need for parameter tuning (e.g., choosing kernels) and introducing adversarial networks. Experiments conducted on real-world corpora indicate that our proposed fairness constraints applied for representation learning can provide better tradeoffs between fairness and utility results than existing approaches.

11.
New Phytol ; 235(5): 1836-1852, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35643887

RESUMO

Salt stress is one of the major environmental factors limiting plant growth and development. Although microtubule (MT) organization is known to be involved in response to salt stress, few tubulin genes have been identified that confer salt insensitivity in plants. In this study, we identified a MT encoding gene, OsTUB1, that increased the survival rate of rice plants under salt stress by stabilizing MT organization and ion transporters. We found that OsTUB1 interacted with Kinesin13A protein, which was essential for OsTUB1-regulated MT organization under salt stress. Further molecular evidence revealed that a OsTUB1-Kinesin13A complex protected rice from salt stress by sustaining membrane-localized Na+ transporter OsHKT1;5, a key regulator of ionic homeostasis. Our results shed light on the function of tubulin and kinesin in regulating MT organization and stabilizing Na+ transporters and Na+ flux at the plasma membrane in rice. The identification of the OsTUB1-Kinesin13A complex provides novel genes for salt insensitivity rice breeding in areas with high soil salinity.


Assuntos
Proteínas de Transporte de Cátions , Oryza , Simportadores , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica de Plantas , Microtúbulos/metabolismo , Oryza/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Sódio/metabolismo , Simportadores/metabolismo , Tubulina (Proteína)/metabolismo
12.
Plant J ; 110(6): 1751-1762, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35404523

RESUMO

Excessive nitrogen fertilizer application is harmful to the environment and reduces the quality of cereal crops. Maintaining crop yields under low nitrogen (LN) conditions and improving quality are important goals for cereal crop breeding. Although the effects of nitrogen assimilation on crop nitrogen-use efficiency (NUE) have been intensively studied, natural variations of the key assimilation genes underlying grain development and quality are largely unclear. Here, we identified an NUE-associated gene, OsGS1;1, encoding glutamine synthase, through genome-wide association analysis, followed by validation experiments and functional analysis. Fifteen single-nucleotide polymorphisms in the OsGS1;1 region led to alternative splicing that generated two functional transcripts: OsGS1;1a and OsGS1;1b. The elite haplotype of OsGS1;1 showed high OsGS1;1b activity, which improved NUE, affected grain development, and reduced amylose content. The results show that OsGS1;1, which is induced under LN conditions, affects grain formation by regulating sugar metabolism and may provide a new avenue for the breeding of high-yield and high-quality rice (Oryza sativa).


Assuntos
Oryza , Processamento Alternativo/genética , Amilose/metabolismo , Grão Comestível/metabolismo , Estudo de Associação Genômica Ampla , Nitrogênio/metabolismo , Oryza/metabolismo , Melhoramento Vegetal
13.
Front Psychol ; 13: 1100172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698591

RESUMO

Introduction: The COVID-19 pandemic continues to impact people's lives and professions worldwide. Chinese nurses face immense work pressure under the normalization of COVID-19 prevention and control, resulting in greater turnover intention. It is, therefore, crucial to study the mechanisms that influence the turnover intention of nurses in this situation. Objective: Many studies have examined the impact of leadership style on nurses' turnover intention; however, few researchers have investigated this influence during the COVID-19 pandemic. Based on the leader-member exchange theory, this study empirically studied the effect of inclusive leadership on turnover intention of nurses under the normalization of COVID-19 prevention and control in China, while assessing the mediating role of psychological ownership. Design: Cross-sectional study with multi-center data. Participants: Two thousand, two hundred ninety-nine registered nurses from 17 hospitals in China were recruited from January to March, 2022, under the normalization of COVID-19 prevention and control in China. Methods: A demographic questionnaire and scales of inclusive leadership, psychological ownership, and turnover intention integrated into an online survey were sent to registered nurses of different hospitals. Maximum likelihood structural equation modeling (ML-SEM) was used to analyze data. Results: Independent variable inclusive leadership has a significant effect on the overall turnover intention of nurses, p < 0.001. The direct effect path coefficient from inclusive leadership to psychological ownership is significant, p < 0.001. The direct effect path coefficient from psychological ownership to turnover intention is significant, p < 0.001. The indirect effect path coefficient from inclusive leadership to turnover intention is significant, p < 0.001. Conclusion: Psychological anxiety, burnout, turnover intention, and even suicidal thoughts were the main symptoms of Chinese nurses under the normalization of COVID-19 prevention and control in China. The absence of a mechanism to counteract these negative conditions may ultimately lead to personal psychological distress for nurses and collapse of the healthcare system. Inclusive leadership can improve nurses' psychological ownership level and reduce their turnover intention by treating them fairly, providing them with opportunities for self-development, paying attention to communication with them, and increasing their sense of belonging, self-efficacy, and self-identity.

14.
Plant Biotechnol J ; 19(1): 167-176, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32710800

RESUMO

Increased use of nitrogen fertilizers has deleterious impact on the environment. Increase in yield potential at low nitrogen supply is regarded as a cereal breeding goal for future agricultural sustainability. Although natural variations of nitrogen transporters have been investigated, key genes associated with assimilation remain largely unexplored for nitrogen use efficiency (NUE) enhancement. Here, we identified a NIN-like protein NLP4 associated with NUE through a GWAS in rice. We found that OsNLP4 transactivated OsNiR encoding nitrite reductase that was critical in nitrogen assimilation in rice. We further constructed quadrupling NREs (Nitrate-responsive cis-elements) in the promoter of OsNiR (p4xNRE:OsNiR) and enhanced nitrogen assimilation significantly. We demonstrated that OsNLP4-OsNiR increased tiller number and yield through enhancing nitrogen assimilation and NUE. Our discovery highlights the genetic modulation of OsNLP4-OsNiR signalling cascade as a strategy for high NUE and yield breeding in rice.


Assuntos
Oryza , Fertilizantes , Nitrogênio , Oryza/genética , Melhoramento Vegetal , Proteínas de Plantas/genética
16.
Soft Matter ; 16(40): 9292-9305, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32930694

RESUMO

Uniform small-sized MOF-Ti nanoparticles were prepared by a one-step hydrothermal method, and then a 5-10 nm TiO2 shell was coated onto them by using the sol-gel method, and MOF-Ti/TiO2 with a specific surface area of 50.2 m2 g-1 was successfully prepared. The nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), nitrogen adsorption-desorption isotherms (BET), and X-ray photoelectron spectroscopy (XPS). The above-analyses have elaborated the experimental study of their morphology, elements, and energy of organic functional groups. At the same time, through the use of a high-voltage rotary rheometer to test their rheological properties, the analysis of shear stress, ER efficiency, shear viscosity, etc. was performed and their dielectric constant and dielectric loss were studied by using a broadband dielectric spectrometer. Finally, we found that MOF-Ti/TiO2 is a new core-shell nanocomposite particle with a small particle size and good electrorheological properties.

17.
Plant Physiol Biochem ; 155: 429-436, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32814279

RESUMO

The bioaccumulation of cadmium (Cd) in crop and the subsequent food chain has aroused extensive concerns. However, the underlying molecular mechanisms of plant Cd tolerance remain to be clarified from the viewpoint of novel candidate genes. Here we described a highly efficient approach for preliminary identifying rice Cd-tolerant genes through the yeast-based cDNA library survival screening combined with high-throughput sequencing strategy. About 690 gene isoforms were identified as being Cd-tolerant candidates using this shotgun approach. Among the Cd-tolerant genes identified, several categories of genes such as BAX inhibitor (BI), NAC transcription factors and Rapid ALkalinization Factors (RALFs) were of particular interest, and their function of Cd tolerance was further validated via heterologous expression, which suggested that SNAC1, RALF12, OsBI-1 can confer Cd tolerance in yeast and tobacco leaves. Regarding the genes involved in ion transport, the validated Cd-tolerant heavy metal-associated domain (HMAD) isoprenylated protein HIPP42 was particularly noteworthy. Further elucidation of these genes associated with Cd tolerance in rice will benefit agricultural activities.


Assuntos
Cádmio/toxicidade , Genes de Plantas , Oryza/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Oryza/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
18.
ISA Trans ; 101: 366-378, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32035636

RESUMO

Early bearing fault detection is crucial to avoid catastrophic accidents. However, the repetitive defect impulses indicating bearing fault are buried in heavy background noise. In the paper, a novel periodical sparse low-rank (PSLR) matrix estimation algorithm is proposed for extracting repetitive transients from noisy signal. Concretely, periodical group sparsity and low-lank property of fault transients in time-frequency domain are first revealed, and then an optimization problem is proposed for simultaneously promoting these two properties. Meanwhile, to further highlight the sparsity of fault features, the non-convex penalty functions are incorporated into the optimization problem. Then, for solving the proposed optimization problem, an iterative algorithm is derived based on alternating direction method of multipliers (ADMM) and majorization-minimization (MM), in which the traditional soft-thresholding operation is replaced by the proposed Gini-guided fault information thresholding (FIT) scheme to enhance fault transient extraction. Finally, simulated and real signals confirm the performance of proposed PSLR in extracting defect impulses from noisy vibration signal.

19.
Funct Plant Biol ; 46(8): 766-776, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31046902

RESUMO

The chloroplast is an essential photosynthetic apparatus that is more sensitive to low temperatures than other organelles. Sigma factors were revealed regulating specific gene expression for maintaining photosynthetic efficiency and adapting to physiological and environmental conditions. However, the regulatory mechanisms of SIG genes supporting chloroplast development under low temperature in rice have not yet been reported. Here, we uncovered the essential role of OsSIG2A in rice chloroplast development at low temperatures by a newly reported thermo-sensitive chlorophyll deficient 12 (tcd12) mutant, which exhibited albino leaves with decreased chlorophyll content and malformed chloroplasts at seedling stage under low temperature. OsSIG2A is a typical chloroplast-localised RNA polymerase sigma factor, and constitutively expresses in different rice tissues, especially for young leaves and stems. Moreover, the transcription level of both PEP- and NEP- dependent genes, which are necessary for chloroplast development at early leaf development stage, was greatly affected in the tcd12 mutant under low temperature. Taken together, our findings indicate that OsSIG2A is required for early chloroplast differentiation under low temperatures by regulating plastid genes expression.


Assuntos
Oryza , Cloroplastos , Proteínas de Plantas , Plastídeos , Temperatura
20.
Int J Mol Sci ; 20(6)2019 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-30909604

RESUMO

Cadmium (Cd) has the potential to be chronically toxic to humans through contaminated crop products. MicroRNAs (miRNAs) can move systemically in plants. To investigate the roles of long-distance moving xylem miRNAs in regulating maize response to Cd stress, three xylem sap small RNA (sRNA) libraries were constructed for high-throughput sequencing to identify potential mobile miRNAs in Cd-stressed maize seedlings and their putative targets in maize transcriptomes. In total, about 199 miRNAs (20⁻22 nucleotides) were identified in xylem sap from maize seedlings, including 97 newly discovered miRNAs and 102 known miRNAs. Among them, 10 miRNAs showed differential expression in xylem sap after 1 h of Cd treatment. Two miRNAs target prediction tools, psRNAtarget (reporting the inhibition pattern of cleavage) and DPMIND (discovering Plant MiRNA-Target Interaction with degradome evidence), were used in combination to identify, via bioinformatics, the targets of 199 significantly expressed miRNAs in maize xylem sap. The integrative results of these two bioinformatic tools suggested that 27 xylem sap miRNAs inhibit 34 genes through cleavage with degradome evidence. Moreover, nearly 300 other genes were also the potential miRNAs cleavable targets without available degradome data support, and the majority of them were enriched in abiotic stress response, cell signaling, transcription regulation, as well as metal handling. These approaches and results not only enhanced our understanding of the Cd-responsive long-distance transported miRNAs from the view of xylem sap, but also provided novel insights for predicting the molecular genetic mechanisms mediated by miRNAs.


Assuntos
Cádmio/metabolismo , Biologia Computacional , MicroRNAs/genética , Estresse Fisiológico/genética , Xilema/fisiologia , Zea mays/fisiologia , Cádmio/toxicidade , Biologia Computacional/métodos , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Interferência de RNA , RNA Mensageiro/genética , Reprodutibilidade dos Testes , Análise de Sequência de RNA
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