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1.
Plant Cell ; 36(1): 40-64, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37811656

RESUMO

Inflorescence architecture is important for rice (Oryza sativa) grain yield. The phytohormone cytokinin (CK) has been shown to regulate rice inflorescence development; however, the underlying mechanism mediated by CK perception is still unclear. Employing a forward genetic approach, we isolated an inactive variant of the CK receptor OHK4/OsHK4 gene named panicle length1, which shows decreased panicle size due to reduced inflorescence meristem (IM) activity. A 2-amino acid deletion in the long α-helix stalk of the sensory module of OHK4 impairs the homodimerization and ligand-binding capacity of the receptor, even though the residues do not touch the ligand-binding domain or the dimerization interface. This deletion impairs CK signaling that occurs through the type-B response regulator OsRR21, which acts downstream of OHK4 in controlling inflorescence size. Meanwhile, we found that IDEAL PLANT ARCHITECTURE1(IPA1)/WEALTHY FARMER'S PANICLE (WFP), encoding a positive regulator of IM development, acts downstream of CK signaling and is directly activated by OsRR21. Additionally, we revealed that IPA1/WFP directly binds to the OHK4 promoter and upregulates its expression through interactions with 2 TCP transcription factors, forming a positive feedback circuit. Altogether, we identified the OHK4-OsRR21-IPA1 regulatory module, providing important insights into the role of CK signaling in regulating rice inflorescence architecture.


Assuntos
Citocininas , Oryza , Humanos , Citocininas/metabolismo , Inflorescência , Oryza/metabolismo , Retroalimentação , Fazendeiros , Ligantes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética
2.
EMBO Rep ; 24(8): e56635, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37358015

RESUMO

Sepsis is a leading cause of in-hospital mortality resulting from a dysregulated response to infection. Novel immunomodulatory therapies targeting macrophage metabolism have emerged as an important focus for current sepsis research. However, understanding the mechanisms underlying macrophage metabolic reprogramming and how they impact immune response requires further investigation. Here, we identify macrophage-expressed Spinster homolog 2 (Spns2), a major transporter of sphingosine-1-phosphate (S1P), as a crucial metabolic mediator that regulates inflammation through the lactate-reactive oxygen species (ROS) axis. Spns2 deficiency in macrophages significantly enhances glycolysis, thereby increasing intracellular lactate production. As a key effector, intracellular lactate promotes pro-inflammatory response by increasing ROS generation. The overactivity of the lactate-ROS axis drives lethal hyperinflammation during the early phase of sepsis. Furthermore, diminished Spns2/S1P signaling impairs the ability of macrophages to sustain an antibacterial response, leading to significant innate immunosuppression in the late stage of infection. Notably, reinforcing Spns2/S1P signaling contributes to balancing the immune response during sepsis, preventing both early hyperinflammation and later immunosuppression, making it a promising therapeutic target for sepsis.


Assuntos
Macrófagos , Sepse , Humanos , Proteínas de Transporte de Ânions/metabolismo , Terapia de Imunossupressão , Lactatos , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Am J Physiol Cell Physiol ; 327(1): C193-C204, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38682240

RESUMO

Negative pressure wound therapy (NPWT) is extensively used in clinical settings to enhance the healing of wounds. Despite its widespread use, the molecular mechanisms driving the efficacy of NPWT have not been fully elucidated. In this study, skin wound-healing models were established, with administration of NPWT. Vimentin, collagen I, and MMP9 of skin tissues were detected by immunofluorescence (IF). Gene expression analysis of skin wound tissues was performed by RNA-sequencing (RNA-seq). Protein expression was assayed by a Western blotting or IF assay, and mRNA levels were quantified by quantitative PCR. Chromatin accessibility profiles of fibroblasts following NPWT or IL-17 exposure were analyzed by ATAC-seq. In rat wound-healing models, NPWT promoted wound repair by promoting reepithelialization, extracellular matrix (ECM) synthesis, and proliferation, which mainly occurred in the early stage of wound healing. These differentially expressed genes (DEGs) in NPWT wounds versus control wounds were enriched in the IL-17 signaling pathway. IL-17 was identified as an upregulated factor following NPWT in skin wounds. Moreover, the IL-17 inhibitor secukinumab (SEC) could abolish the promoting effect of NPWT on wound healing. Importantly, chromatin accessibility profiles were altered following NPWT and IL-17 stimulation in skin fibroblasts. Our findings suggest that NPWT upregulates IL-17 to promote wound healing by altering chromatin accessibility, which is a novel mechanism for NPWT's efficacy in wound healing.NEW & NOTEWORTHY To our knowledge, this is the first report of the efficacy of negative pressure wound therapy (NPWT) in promoting wound healing via IL-17. Moreover, NPWT and IL-17 can alter chromatin accessibility. Our study identifies a novel mechanism for NPWT's efficacy in wound healing.


Assuntos
Cromatina , Interleucina-17 , Tratamento de Ferimentos com Pressão Negativa , Ratos Sprague-Dawley , Cicatrização , Animais , Interleucina-17/metabolismo , Interleucina-17/genética , Tratamento de Ferimentos com Pressão Negativa/métodos , Cicatrização/efeitos dos fármacos , Ratos , Cromatina/metabolismo , Cromatina/genética , Masculino , Pele/lesões , Pele/metabolismo , Pele/patologia , Pele/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Transdução de Sinais
4.
Artigo em Inglês | MEDLINE | ID: mdl-38625507

RESUMO

Polymyxin B (PMB) is considered a last-line treatment for multidrug-resistant (MDR) gram-negative bacterial infections. Model-informed precision dosing with population pharmacokinetics (PopPK) models could help to individualize PMB dosing regimens and improve therapy. However, the external prediction ability of the established PopPK models has not been fully elaborated. This study aimed to systemically evaluate eleven PMB PopPK models from ten published literature based on a new independent population, which was divided into four different populations, patients with liver dysfunction, kidney dysfunction, liver and kidney dysfunction, and normal liver and kidney function. The whole data set consisted of 146 patients with 391 PMB concentrations. The prediction- and simulation-based diagnostics and Bayesian forecasting were conducted to evaluate model predictability. In the overall evaluation process, none of the models exhibited satisfactory predictive ability in both prediction- and simulation-based diagnostic simultaneously. However, the evaluation of the models in the subgroup of patients with normal liver and kidney function revealed improved predictive performance compared to those with liver and/or kidney dysfunction. Bayesian forecasting demonstrated enhanced predictability with the incorporation of two to three prior observations. The external evaluation highlighted a lack of consistency between the prediction results of published models and the external validation dataset. Nonetheless, Bayesian forecasting holds promise in improving the predictive performance of the models, and feedback from therapeutic drug monitoring is crucial in optimizing individual dosing regimens.

5.
Planta ; 257(4): 71, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36862199

RESUMO

MAIN CONCLUSIONS: STD1 specifically interacts with MAP65-5 in rice and they cooperatively control microtubule bundles in phragmoplast expansion during cell division. Microtubules play critical roles during the cell cycle progression in the plant cell. We previously reported that STEMLESS DWARF 1 (STD1), a kinesin-related protein, was localized specifically to the phragmoplast midzone during telophase to regulate the lateral expansion of phragmoplast in rice (Oryza sativa). However, how STD1 regulates microtubule organization remains unknown. Here, we found that STD1 interacted directly with MAP65-5, a member of the microtubule-associated proteins (MAPs). Both STD1 and MAP65-5 could form homodimers and bundle microtubules individually. Compared with MAP65-5, the microtubules bundled by STD1 were disassembled completely into single microtubules after adding ATP. Conversely, the interaction of STD1 with MAP65-5 enhanced the microtubule bundling. These results suggest STD1 and MAP65-5 might cooperatively regulate microtubule organization in the phragmoplast at telophase.


Assuntos
Proteínas Associadas aos Microtúbulos , Oryza , Proteínas Associadas aos Microtúbulos/genética , Cinesinas , Microtúbulos , Mitose
6.
Br J Clin Pharmacol ; 89(12): 3561-3572, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37461291

RESUMO

AIMS: Polymyxin B (PMB) is widely used to treat infections caused by multidrug-resistant Gram-negative pathogens. Currently, the pharmacokinetic data of PMB in patients with liver dysfunction are limited. This study aimed to develop a population pharmacokinetic (PopPK) model of PMB in patients with liver dysfunction and identify the factors affecting PMB pharmacokinetics. METHODS: We conducted a retrospective pharmacokinetic study involving 136 adults with different levels of liver function. Nonlinear mixed effects modelling was used to develop a PopPK model of PMB. Monte Carlo simulation was used to design PMB dosage schedules across various liver and renal functions. RESULTS: PMB pharmacokinetic analyses included 401 steady-state concentrations in 136 adult patients. A one-compartment pharmacokinetic model with first-order absorption and elimination was used to describe the data. The typical population value of PMB clearance was 2.43 L/h and the volume of distribution was 23.11 L. This study revealed that creatinine clearance (CrCL) and Child-Pugh class were significantly associated with PMB pharmacokinetic parameters; however, clinically relevant variations of dose-normalized drug exposure were not significant. For patients with a minimum inhibitory concentration of ≤0.5 mg/L, the appropriate dose was 40-75 mg/12-h. When the dose exceeded 100 mg/12-h, the risk of nephrotoxicity increased significantly. CONCLUSIONS: This study provided PMB pharmacokinetic information for patients with liver dysfunction. Patients with renal and liver dysfunctions may not require an initial dose adjustment. Rather than PopPK-guided dose adjustment, therapeutic drug monitoring of PMB plays a more direct role in optimizing dosing regimens based on its therapeutic window.


Assuntos
Hepatopatias , Polimixina B , Adulto , Humanos , Polimixina B/efeitos adversos , Polimixina B/farmacocinética , Estudos Retrospectivos , Rim , Antibacterianos
7.
Methods ; 204: 142-150, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35477057

RESUMO

DNA N6-methyladenine (6mA) is a key DNA modification, which plays versatile roles in the cellular processes, including regulation of gene expression, DNA repair, and DNA replication. DNA 6mA is closely associated with many diseases in the mammals and with growth as well as development of plants. Precisely detecting DNA 6mA sites is of great importance to exploration of 6mA functions. Although many computational methods have been presented for DNA 6mA prediction, there is still a wide gap in the practical application. We presented a convolution neural network (CNN) and bi-directional long-short term memory (Bi-LSTM)-based deep learning method (Deep6mAPred) for predicting DNA 6mA sites across plant species. The Deep6mAPred stacked the CNNs and the Bi-LSTMs in a paralleling manner instead of a series-connection manner. The Deep6mAPred also employed the attention mechanism for improving the representations of sequences. The Deep6mAPred reached an accuracy of 0.9556 over the independent rice dataset, far outperforming the state-of-the-art methods. The tests across plant species showed that the Deep6mAPred is of a remarkable advantage over the state of the art methods. We developed a user-friendly web application for DNA 6mA prediction, which is freely available at http://106.13.196.152:7001/ for all the scientific researchers. The Deep6mAPred would enrich tools to predict DNA 6mA sites and speed up the exploration of DNA modification.


Assuntos
Metilação de DNA , Aprendizado Profundo , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Animais , DNA/metabolismo , Mamíferos/genética
8.
New Phytol ; 234(1): 122-136, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34716593

RESUMO

Shoot branching is regulated by multiple signals. Previous studies have indicated that sucrose may promote shoot branching through suppressing the inhibitory effect of the hormone strigolactone (SL). However, the molecular mechanisms underlying this effect are unknown. Here, we used molecular and genetic tools to identify the molecular targets underlying the antagonistic interaction between sucrose and SL. We showed that sucrose antagonizes the suppressive action of SL on tillering in rice and on the degradation of D53, a major target of SL signalling. Sucrose inhibits the gene expression of D3, the orthologue of the Arabidopsis F-box MAX2 required for SL signalling. Overexpression of D3 antagonizes sucrose inhibition of D53 degradation and enables the SL inhibition of tillering under high sucrose. Sucrose prevents SL-induced degradation of D14, the SL receptor involved in D53 degradation. In contrast to D3, D14 overexpression enhances D53 protein levels and sucrose-induced tillering, even in the presence of SL. Our results show that sucrose inhibits SL response by affecting key components of SL signalling and, together with previous studies reporting the inhibition of SL synthesis by nitrate and phosphate, demonstrate the central role played by SLs in the regulation of plant architecture by nutrients.


Assuntos
Arabidopsis , Oryza , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Lactonas/metabolismo , Lactonas/farmacologia , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sacarose/metabolismo , Sacarose/farmacologia
9.
Plant Physiol ; 185(4): 1722-1744, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793928

RESUMO

Moderate leaf rolling is beneficial for leaf erectness and compact plant architecture. However, our understanding regarding the molecular mechanisms of leaf rolling is still limited. Here, we characterized a semi-dominant rice (Oryza sativa L.) mutant upward rolled leaf 1 (Url1) showing adaxially rolled leaves due to a decrease in the number and size of bulliform cells. Map-based cloning revealed that URL1 encodes the homeodomain-leucine zipper (HD-Zip) IV family member RICE OUTERMOST CELL-SPECIFIC 8 (ROC8). A single-base substitution in one of the two conserved complementary motifs unique to the 3'-untranslated region of this family enhanced URL1 mRNA stability and abundance in the Url1 mutant. URL1 (UPWARD ROLLED LEAF1) contains an ethylene-responsive element binding factor-associated amphiphilic repression motif and functions as a transcriptional repressor via interaction with the TOPLESS co-repressor OsTPL2. Rather than homodimerizing, URL1 heterodimerizes with another HD-ZIP IV member ROC5. URL1 could bind directly to the promoter and suppress the expression of abaxially curled leaf 1 (ACL1), a positive regulator of bulliform cell development. Knockout of OsTPL2 or ROC5 or overexpression of ACL1 in the Url1 mutant partially suppressed the leaf-rolling phenotype. Our results reveal a regulatory network whereby a transcriptional repression complex composed of URL1, ROC5, and the transcriptional corepressor TPL2 suppresses the expression of the ACL1 gene, thus modulating bulliform cell development and leaf rolling in rice.


Assuntos
Oryza/citologia , Oryza/crescimento & desenvolvimento , Oryza/genética , Folhas de Planta/citologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Fatores de Transcrição/metabolismo , Proliferação de Células/genética , Proliferação de Células/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Mutação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
10.
Plant Physiol ; 186(1): 497-518, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33591317

RESUMO

Leaf morphology influences photosynthesis, transpiration, and ultimately crop yield. However, the molecular mechanism of leaf development is still not fully understood. Here, we identified and characterized the narrow leaf21 (nal21) mutant in rice (Oryza sativa), showing a significant reduction in leaf width, leaf length and plant height, and increased tiller number. Microscopic observation revealed defects in the vascular system and reduced epidermal cell size and number in the nal21 leaf blade. Map-based cloning revealed that NAL21 encodes a ribosomal small subunit protein RPS3A. Ribosome-targeting antibiotics resistance assay and ribosome profiling showed a significant reduction in the free 40S ribosome subunit in the nal21 mutant. The nal21 mutant showed aberrant auxin responses in which multiple auxin response factors (ARFs) harboring upstream open-reading frames (uORFs) in their 5'-untranslated region were repressed at the translational level. The WUSCHEL-related homeobox 3A (OsWOX3A) gene, a key transcription factor involved in leaf blade lateral outgrowth, is also under the translational regulation by RPS3A. Transformation with modified OsARF11, OsARF16, and OsWOX3A genomic DNA (gDNA) lacking uORFs rescued the narrow leaf phenotype of nal21 to a better extent than transformation with their native gDNA, implying that RPS3A could regulate translation of ARFs and WOX3A through uORFs. Our results demonstrate that proper translational regulation of key factors involved in leaf development is essential to maintain normal leaf morphology.


Assuntos
Oryza/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas Ribossômicas/genética , Oryza/crescimento & desenvolvimento , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Proteínas Ribossômicas/metabolismo
11.
J Clin Pharm Ther ; 47(9): 1426-1437, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35633089

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Carbapenem-resistant Gram-negative bacterial pathogens continue to threaten public health. Avibactam (AVI), a novel non-ß-lactam ß-lactamase inhibitor, has been approved for use with ceftazidime (CAZ) mainly against carbapenem-resistant Enterobacteriaceae. Therapeutic drug monitoring (TDM) is urgently needed to optimize dosage regimens to maximize efficacy, minimize toxicity, and delay the emergence of resistance. This study aims to develop and validate a rapid, simple, and economical LC-MS/MS method for simultaneous determination of CAZ/AVI in human plasma. METHODS: Samples were processed by simple protein precipitation, and gradient elution strategy was applied to separate CAZ and AVI on a reverse-phase C18 column; with subsequent detection by the mass spectrometer in a positive and negative ion switching mode. Plasma samples from patients were analysed. RESULTS AND DISCUSSION: A 4-min run of LC-MS/MS was developed. The precision, trueness, matrix effect, extraction recovery, carry-over, dilution integrity, and stability were all acceptable for a bioanalytical method. The method was successfully applied to the determination of CAZ and AVI in patients, and a considerable PK variability of CAZ/AVI was observed among patients. WHAT IS NEW AND CONCLUSION: A robust, rapid, simple, and economical LC-MS/MS method for the simultaneous determination of CAZ and AVI was developed. The considerable PK variability of CAZ/AVI among patients demonstrates the clinical significance of TDM.


Assuntos
Ceftazidima , Inibidores de beta-Lactamases , Antibacterianos/uso terapêutico , Compostos Azabicíclicos , Carbapenêmicos/uso terapêutico , Ceftazidima/farmacologia , Ceftazidima/uso terapêutico , Cromatografia Líquida , Combinação de Medicamentos , Monitoramento de Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Espectrometria de Massas em Tandem , Inibidores de beta-Lactamases/uso terapêutico
12.
Bioprocess Biosyst Eng ; 45(2): 353-364, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34797400

RESUMO

The combined cross-linked enzyme aggregates (combi-CLEAs) containing galactitol dehydrogenase (Gdh) and NADH oxidase (Nox) were prepared for L-tagatose synthesis. To prevent the excess consumption of cofactor, Nox in the combi-CLEAs was used to in situ regenerate NAD+. In the immobilization process, ammonia sulfate and glutaraldehyde were used as the precipitant and cross-linking reagent, respectively. The preparation conditions were optimized as follows: 60% ammonium sulfate, 1:1 (molar ratio) of Gdh to Nox, 20:1 (molar ratio) of protein to glutaraldehyde, and 6 h of cross-linking time at 35 °C. Under these conditions, the activity of the combi-CLEAs was 210 U g-1. The combi-CLEAs exhibited higher thermostability and preserved 51.5% of the original activity after eight cycles of reuses at 45 °C. The combi-CLEAs were utilized for the preparation of L-tagatose without by-products. Therefore, the combi-CLEAs have the industrial potential for the bioconversion of galactitol to L-tagatose.


Assuntos
Enzimas Imobilizadas , Hexoses , Regeneração , Reagentes de Ligações Cruzadas , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Hexoses/biossíntese , Hexoses/química , Complexos Multienzimáticos , NADH NADPH Oxirredutases , Desidrogenase do Álcool de Açúcar
13.
BMC Bioinformatics ; 22(1): 430, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496745

RESUMO

BACKGROUND: Essential proteins have great impacts on cell survival and development, and played important roles in disease analysis and new drug design. However, since it is inefficient and costly to identify essential proteins by using biological experiments, then there is an urgent need for automated and accurate detection methods. In recent years, the recognition of essential proteins in protein interaction networks (PPI) has become a research hotspot, and many computational models for predicting essential proteins have been proposed successively. RESULTS: In order to achieve higher prediction performance, in this paper, a new prediction model called TGSO is proposed. In TGSO, a protein aggregation degree network is constructed first by adopting the node density measurement method for complex networks. And simultaneously, a protein co-expression interactive network is constructed by combining the gene expression information with the network connectivity, and a protein co-localization interaction network is constructed based on the subcellular localization data. And then, through integrating these three kinds of newly constructed networks, a comprehensive protein-protein interaction network will be obtained. Finally, based on the homology information, scores can be calculated out iteratively for different proteins, which can be utilized to estimate the importance of proteins effectively. Moreover, in order to evaluate the identification performance of TGSO, we have compared TGSO with 13 different latest competitive methods based on three kinds of yeast databases. And experimental results show that TGSO can achieve identification accuracies of 94%, 82% and 72% out of the top 1%, 5% and 10% candidate proteins respectively, which are to some degree superior to these state-of-the-art competitive models. CONCLUSIONS: We constructed a comprehensive interactive network based on multi-source data to reduce the noise and errors in the initial PPI, and combined with iterative methods to improve the accuracy of necessary protein prediction, and means that TGSO may be conducive to the future development of essential protein recognition as well.


Assuntos
Biologia Computacional , Mapas de Interação de Proteínas , Algoritmos , Mapeamento de Interação de Proteínas , Proteínas/genética , Proteínas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
14.
Anal Biochem ; 612: 114021, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33189704

RESUMO

We developed a binary vector co-expressing firefly luciferase (FF) and Renilla luciferase (REN) to detect protein stability in response to different stimuli, and verified the functionality of the vector. The StrigoQuant-like reporter expressing FF and REN in one transcript is a sensitive tool for detecting protein abundance in different genotypes. However, we found that significant differences in the relative FF/REN ratio of empty StrigoQuant vector in different genotypes. Therefore, to determine the actual protein abundance, the relative FF/REN ratio of the protein of interest should be normalized to that of the empty vector.


Assuntos
Bioensaio/métodos , Genes Reporter , Luciferases/metabolismo , Estabilidade Proteica , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Vetores Genéticos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Indicadores e Reagentes/química , Lactonas/farmacologia , Luciferases de Vaga-Lume/genética , Luciferases de Renilla/genética , Oryza/metabolismo , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Protoplastos/metabolismo , Nicotiana/metabolismo
15.
Hum Genomics ; 14(1): 14, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252824

RESUMO

BACKGROUND: Essential proteins are an important part of the cell and closely related to the life activities of the cell. Hitherto, Protein-Protein Interaction (PPI) networks have been adopted by many computational methods to predict essential proteins. Most of the current approaches focus mainly on the topological structure of PPI networks. However, those methods relying solely on the PPI network have low detection accuracy for essential proteins. Therefore, it is necessary to integrate the PPI network with other biological information to identify essential proteins. RESULTS: In this paper, we proposed a novel random walk method for identifying essential proteins, called HEPT. A three-dimensional tensor is constructed first by combining the PPI network of Saccharomyces cerevisiae with multiple biological data such as gene ontology annotations and protein domains. Then, based on the newly constructed tensor, we extended the Hyperlink-Induced Topic Search (HITS) algorithm from a two-dimensional to a three-dimensional tensor model that can be utilized to infer essential proteins. Different from existing state-of-the-art methods, the importance of proteins and the types of interactions will both contribute to the essential protein prediction. To evaluate the performance of our newly proposed HEPT method, proteins are ranked in the descending order based on their ranking scores computed by our method and other competitive methods. After that, a certain number of the ranked proteins are selected as candidates for essential proteins. According to the list of known essential proteins, the number of true essential proteins is used to judge the performance of each method. Experimental results show that our method can achieve better prediction performance in comparison with other nine state-of-the-art methods in identifying essential proteins. CONCLUSIONS: Through analysis and experimental results, it is obvious that HEPT can be used to effectively improve the prediction accuracy of essential proteins by the use of HITS algorithm and the combination of network topology with gene ontology annotations and protein domains, which provides a new insight into multi-data source fusion.


Assuntos
Algoritmos , Biologia Computacional/métodos , Simulação por Computador , Mapas de Interação de Proteínas , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo
16.
New Phytol ; 225(1): 356-375, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31433495

RESUMO

Degeneration of apical spikelets and reduced panicle fertility are common reasons for low seed-setting rate in rice (Oryza sativa). However, little is known about the underlying molecular mechanisms. Here, we report a novel degenerated panicle and partial sterility 1 (dps1) mutant that showed panicle apical degeneration and reduced fertility in middle spikelets. dps1 plants were characterized by small whitish anthers with altered cuticle morphology and absence of pollen grains. Amounts of cuticular wax and cutin were significantly reduced in dps1 anthers. Panicles of dps1 plants showed an accumulation of reactive oxygen species (ROS), lower antioxidant activity, and increased programmed cell death. Map-based cloning revealed that DPS1 encodes a mitochondrial-localized protein containing a cystathionine ß-synthase domain that showed the highest expression in panicles and anthers. DPS1 physically interacted with mitochondrial thioredoxin proteins Trx1 and Trx20, and it participated in ROS scavenging. Global gene expression analysis in dps1 revealed that biological processes related to fatty acid metabolism and ROS homeostasis were significantly affected, and the expression of key genes involved in wax and cutin biosynthesis were downregulated. These results suggest that DPS1 plays a vital role in regulating ROS homeostasis, anther cuticle formation, and panicle development in rice.


Assuntos
Cistationina beta-Sintase/química , Flores/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Morte Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Peróxido de Hidrogênio/toxicidade , Lipídeos de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mutação/genética , Oryza/efeitos dos fármacos , Oryza/genética , Fenótipo , Proteínas de Plantas/genética , Pólen/efeitos dos fármacos , Pólen/metabolismo , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Transcriptoma/genética , Ceras/metabolismo
17.
J Exp Bot ; 71(2): 470-479, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31644801

RESUMO

Abiotic stresses, including drought, salinity, temperature, and heavy metals, pose a major challenge for crop production and cause substantial yield reduction worldwide. Breeding tolerant cultivars against these abiotic stresses is the most sustainable and eco-friendly approach to cope with this challenge. Advances in genome editing technologies provide new opportunities for crop improvement by employing precision genome engineering for targeted crop traits. However, the selection of the candidate genes is critical for the success of achieving the desired traits. Broadly speaking, these genes could fall into two major categories, structural and regulatory genes. Structural genes encode proteins that provide stress tolerance directly, whereas regulatory genes act indirectly by controlling the expression of other genes involved in different cellular processes. Additionally, cis-regulatory sequences are also vital for achieving stress tolerance. We propose targeting of these regulatory and/or structural genes along with the cis-regulatory sequences via the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system as a robust, efficient, and practical approach for developing crop varieties resilient to climate change. We also discuss the possibility of creating novel quantitative trait loci for abiotic stress tolerance via the CRISPR/Cas-mediated targeting of promoters. It is hoped that these genome editing tools will not only make a significant contribution towards raising novel plant types having tolerance to multiple abiotic stresses but will also aid in public acceptance of these products in years to come. This article is an attempt to critically evaluate the suitability of available tools and the target genes for obtaining plants with improved tolerance to abiotic stresses.


Assuntos
Sistemas CRISPR-Cas , Produtos Agrícolas/fisiologia , Melhoramento Vegetal , Plantas Geneticamente Modificadas/fisiologia , Estresse Fisiológico , Produtos Agrícolas/genética , Edição de Genes , Plantas Geneticamente Modificadas/genética
18.
BMC Bioinformatics ; 20(1): 626, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31795943

RESUMO

BACKGROUND: In recent years, lncRNAs (long-non-coding RNAs) have been proved to be closely related to the occurrence and development of many serious diseases that are seriously harmful to human health. However, most of the lncRNA-disease associations have not been found yet due to high costs and time complexity of traditional bio-experiments. Hence, it is quite urgent and necessary to establish efficient and reasonable computational models to predict potential associations between lncRNAs and diseases. RESULTS: In this manuscript, a novel prediction model called TCSRWRLD is proposed to predict potential lncRNA-disease associations based on improved random walk with restart. In TCSRWRLD, a heterogeneous lncRNA-disease network is constructed first by combining the integrated similarity of lncRNAs and the integrated similarity of diseases. And then, for each lncRNA/disease node in the newly constructed heterogeneous lncRNA-disease network, it will establish a node set called TCS (Target Convergence Set) consisting of top 100 disease/lncRNA nodes with minimum average network distances to these disease/lncRNA nodes having known associations with itself. Finally, an improved random walk with restart is implemented on the heterogeneous lncRNA-disease network to infer potential lncRNA-disease associations. The major contribution of this manuscript lies in the introduction of the concept of TCS, based on which, the velocity of convergence of TCSRWRLD can be quicken effectively, since the walker can stop its random walk while the walking probability vectors obtained by it at the nodes in TCS instead of all nodes in the whole network have reached stable state. And Simulation results show that TCSRWRLD can achieve a reliable AUC of 0.8712 in the Leave-One-Out Cross Validation (LOOCV), which outperforms previous state-of-the-art results apparently. Moreover, case studies of lung cancer and leukemia demonstrate the satisfactory prediction performance of TCSRWRLD as well. CONCLUSIONS: Both comparative results and case studies have demonstrated that TCSRWRLD can achieve excellent performances in prediction of potential lncRNA-disease associations, which imply as well that TCSRWRLD may be a good addition to the research of bioinformatics in the future.


Assuntos
Algoritmos , Biologia Computacional/métodos , Estudos de Associação Genética , Predisposição Genética para Doença , RNA Longo não Codificante/genética , Área Sob a Curva , Humanos , Neoplasias/genética , Probabilidade , RNA Longo não Codificante/metabolismo , Reprodutibilidade dos Testes
19.
Plant J ; 96(3): 620-634, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30071144

RESUMO

Several kinesins, the ATP-driven microtubule (MT)-based motor proteins, have been reported to be involved in many basic processes of plant development; however, little is known about the biological relevance of their ATPase activity. Here, we characterized the Oryza sativa (rice) stemless dwarf 1 (std1) mutant, showing a severely dwarfed phenotype, with no differentiation of the node and internode structure, abnormal cell shapes, a shortened leaf division zone and a reduced cell division rate. Further analysis revealed that a substantial subset of cells was arrested in the S and G2/M phases, and multinucleate cells were present in the std1 mutant. Map-based cloning revealed that STD1 encodes a phragmoplast-associated kinesin-related protein, a homolog of the Arabidopsis thaliana PAKRP2, and is mainly expressed in the actively dividing tissues. The STD1 protein is localized specifically to the phragmoplast midzone during telophase and cytokinesis. In the std1 mutant, the substitution of Val-40-Glu in the motor domain of STD1 significantly reduced its MT-dependent ATPase activity. Accordingly, the lateral expansion of phragmoplast, a key step in cell plate formation, was arrested during cytokinesis. Therefore, these results indicate that the MT-dependent ATPase activity is indispensible for STD1 in regulating normal cell division and organ development.


Assuntos
Adenosina Trifosfatases/metabolismo , Divisão Celular , Cinesinas/metabolismo , Oryza/enzimologia , Adenosina Trifosfatases/genética , Citocinese , Mitose , Oryza/genética , Oryza/crescimento & desenvolvimento , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
20.
Int J Mol Sci ; 20(10)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130602

RESUMO

Leaf blade width, curvature, and cuticular wax are important agronomic traits of rice. Here, we report the rice Oschr4-5 mutant characterized by pleiotropic phenotypes, including narrow and rolled leaves, enhanced cuticular wax deposition and reduced plant height and tiller number. The reduced leaf width is caused by a reduced number of longitudinal veins and increased auxin content. The cuticular wax content was significantly higher in the Oschr4-5 mutant, resulting in reduced water loss rate and enhanced drought tolerance. Molecular characterization reveals that a single-base deletion results in a frame-shift mutation from the second chromodomain of OsCHR4, a CHD3 (chromodomain helicase DNA-binding) family chromatin remodeler, in the Oschr4-5 mutant. Expressions of seven wax biosynthesis genes (GL1-4, WSL4, OsCER7, LACS2, LACS7, ROC4 and BDG) and four auxin biosynthesis genes (YUC2, YUC3, YUC5 and YUC6) was up-regulated in the Oschr4-5 mutant. Chromatin immunoprecipitation assays revealed that the transcriptionally active histone modification H3K4me3 was increased, whereas the repressive H3K27me3 was reduced in the upregulated genes in the Oschr4-5 mutant. Therefore, OsCHR4 regulates leaf morphogenesis and cuticle wax formation by epigenetic modulation of auxin and wax biosynthetic genes expression.


Assuntos
DNA Helicases/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Montagem e Desmontagem da Cromatina , Secas , Epigênese Genética , Mutação da Fase de Leitura , Oryza/fisiologia , Oryza/ultraestrutura , Fenótipo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/ultraestrutura , Plantas Geneticamente Modificadas/fisiologia , Plantas Geneticamente Modificadas/ultraestrutura , Estresse Fisiológico , Ceras/análise , Ceras/metabolismo
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