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1.
Ann Hematol ; 103(6): 2089-2102, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38691145

RESUMO

Infection post-hematopoietic stem cell transplantation (HSCT) is one of the main causes of patient mortality. Fever is the most crucial clinical symptom indicating infection. However, current microbial detection methods are limited. Therefore, timely diagnosis of infectious fever and administration of antimicrobial drugs can effectively reduce patient mortality. In this study, serum samples were collected from 181 patients with HSCT with or without infection, as well as the clinical information. And more than 80 infectious-related microRNAs in the serum were selected according to the bulk RNA-seq result and detected in the 345 time-pointed serum samples by Q-PCR. Unsupervised clustering result indicates a close association between these microRNAs expression and infection occurrence. Compared to the uninfected cohort, more than 10 serum microRNAs were identified as the combined diagnostic markers in one formula constructed by the Random Forest (RF) algorithms, with a diagnostic accuracy more than 0.90. Furthermore, correlations of serum microRNAs to immune cells, inflammatory factors, pathgens, infection tissue, and prognosis were analyzed in the infection cohort. Overall, this study demonstrates that the combination of serum microRNAs detection and machine learning algorithms holds promising potential in diagnosing infectious fever after HSCT.


Assuntos
Febre , Transplante de Células-Tronco Hematopoéticas , Aprendizado de Máquina , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Febre/etiologia , Febre/diagnóstico , Febre/sangue , Algoritmos , MicroRNAs/sangue , Biomarcadores/sangue , Adolescente , Adulto Jovem
2.
Plant Cell Rep ; 42(2): 433-448, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36693991

RESUMO

KEY MESSAGE: Ectopic expression of MmCYP1A1 gene from Mus musculus in apple calli and Arabidopsis increased the levels of melatonin and 6-hydroxymelatonin, and improved their stress resistance. Melatonin occurs widely in organisms, playing a key regulatory role. CYP1A1 is a cytochrome P450 monooxygenase, involved in the melatonin metabolism, and is responsible for the synthesis of 6-hydroxymelatonin from melatonin. Melatonin and 6-hydroxymelatonin have strong antioxidant activities in animals. Here, we cloned MmCYP1A1 from Mus musculus and found that ectopic expression of MmCYP1A1 improved the levels of melatonin and 6-hydroxymelatonin in transgenic apple calli and Arabidopsis. Subsequently, we observed that MmCYP1A1 increased the tolerance of transgenic apple calli and Arabidopsis to osmotic stress simulated by polyethylene glycol 6000 (PEG 6000), as well as resistance of transgenic Arabidopsis to drought stress. Further, the number of lateral roots of MmCYP1A1 transgenic Arabidopsis were enhanced significantly after PEG 6000 treatment. The expression of MmCYP1A1 remarkably reduced malondialdehyde (MDA) content, electrolyte leakage, accumulation of H2O2 and O2- during stress treatment. Moreover, MmCYP1A1 enhanced stress tolerance in apple calli and Arabidopsis by increasing the expression levels of resistance genes. MmCYP1A1 also promoted stomatal closure in transgenic Arabidopsis to reduce leaf water loss during drought. Our results indicate that MmCYP1A1 plays a key role in plant stress tolerance, which may provide a reference for future plant stress tolerance studies.


Assuntos
Arabidopsis , Malus , Melatonina , Animais , Camundongos , Arabidopsis/genética , Arabidopsis/metabolismo , Malus/genética , Malus/metabolismo , Melatonina/metabolismo , Expressão Ectópica do Gene , Peróxido de Hidrogênio/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Regulação da Expressão Gênica de Plantas , Secas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 48(2): 430-442, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725233

RESUMO

The chemical constituents in stem leaf, root, and flower of Ixeris sonchifolia were identified by the ultra performance li-quid chromatography coupled with linear ion trap quadrupole-orbitrap mass spectrometry(UPLC-LTQ-Orbitrap-MS~n). The separation was performed on an Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 µm) with a mobile phase of water(containing 0.1% formic acid, A)-acetonitrile(B) with gradient elution. With electrospray ionization source, the data of 70% methanol extract from stem leaf, root and flower of I. sonchifolia were collected by high-resolution full-scan Fourier transform spectroscopy, data dependent acquisition, precursor ion scan, and selected ion monitoring in the negative and positive ion modes. The compounds were identified based on accurate molecular weight, retention time, fragment ions, comparison with reference standard, Clog P and references. A total of 131 compounds were identified from the 70% methanol extract of I. sonchifolia, including nucleosides, flavonoids, organic acids, terpenoids, and phenylpropanoids, and 119, 110, and 126 compounds were identified from the stem leaf, root and flower of I. sonchifolia, respectively. In addition, isorhamnetin, isorhamnetin-7-O-sambubioside and caffeylshikimic acid were discovered from I. sonchifolia for the first time. This study comprehensively analyzed and compared the chemical constituents in different parts of I. sonchifolia, which facilitated the discovery of effective substances and the development and application of medicinal material resources of I. sonchifolia.


Assuntos
Asteraceae , Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/química , Metanol , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas
4.
Plant Physiol ; 186(1): 750-766, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33764451

RESUMO

Nitrate acts as a vital signal molecule in the modulation of plant growth and development. The phytohormones gibberellin (GA) is also involved in this process. However, the exact molecular mechanism of how nitrate and GA signaling pathway work together in regulating plant growth remains poorly understood. In this study, we found that a nitrate-responsive BTB/TAZ protein MdBT2 participates in regulating nitrate-induced plant growth in apple (Malus × domestica). Yeast two-hybridization, protein pull-down, and bimolecular fluorescence complementation (BiFC) assays showed that MdBT2 interacts with a DELLA protein MdRGL3a, which is required for the ubiquitination and degradation of MdRGL3a proteins via a 26S proteasome-dependent pathway. Furthermore, heterologous expression of MdBT2 partially rescued growth inhibition caused by overexpression of MdRGL3a in Arabidopsis. Taken together, our findings indicate that MdBT2 promotes nitrate-induced plant growth partially through reducing the abundance of the DELLA protein MdRGL3a.


Assuntos
Malus/genética , Nitratos/metabolismo , Proteínas de Plantas/genética , Malus/crescimento & desenvolvimento , Malus/metabolismo , Proteínas de Plantas/metabolismo
5.
Biomed Chromatogr ; 36(2): e5276, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741336

RESUMO

3,4-Dicaffeoylquinic acid (3,4-DiCQA) is a dicaffeoylquinic acid that possesses antioxidant, anti-inflammatory, antibacterial, antiviral, anticancer, hypoglycemic, hypotensive, and hepatoprotective activities. This study developed a rapid and reliable method using ultra-high performance liquid chromatography equipped with linear ion trap-Orbitrap MS to identify the metabolites of 3,4-DiCQA in rat plasma, urine, feces, and tissues. The metabolic profile of 3,4-DiCQA was determined after an oral administration of 200 mg/kg to rats. A strategy of full scan-parent ions list acquisition coupled to diagnostic product ion analysis for screening and identification of target metabolites was used. A total of 67 metabolites, combined with accurate mass measurement, diagnostic ions, neutral losses, and reference standards, were observed and characterized for the first time. The results indicated that hydrolysis, methylation, hydrogenation, hydration, dehydroxylation, dehydrogenation, sulfate conjugation, and glucuronide conjugation were the major metabolic reactions of 3,4-DiCQA in vivo.


Assuntos
Ácido Clorogênico/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Animais , Biomarcadores/análise , Biomarcadores/química , Biomarcadores/metabolismo , Ácido Clorogênico/análise , Ácido Clorogênico/química , Ácido Clorogênico/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
6.
Fungal Genet Biol ; 149: 103531, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33581364

RESUMO

Fungi activate corresponding metabolic pathways in response to different carbon sources to adapt to different environments. Previous studies have shown that the glycerol kinase GlcA that phosphorylates glycerol to the intermediate glycerol-3-phosphate (G3P) is required for the growth of Aspergillus fumigatus when glycerol is used as the sole carbon source. The present study identified there were two putative glycerol kinases, GlcA and GlcB, in A. fumigatus but glycerol activated only glcA promoter but not glcB promoter, although both glcA and glcB could encode glycerol kinase. Under normal culture conditions, the absence of glcA caused no detectable colony phenotypes on glucose and other tested carbon sources except glycerol, indicating dissimilation of glucose and these tested carbon sources bypassed requirement of glcA. Notably, the oxidative stress agent H2O2 on the background of glucose medium clearly induced GlcA expression and promoted G3P synthesis. Deletion and overexpression of glcA elicited sensitivity and resistance to oxidative stress agent H2O2, respectively, accompanied by decrease and increase of G3P production. In addition, the sensitivity to oxidative stress in the glcA mutant was probably associated with dysfunction of mitochondria with a decreased mitochondrial membrane potential and an abnormal accumulation of the cellular reactive oxygen species (ROS). Furthermore, overexpressing the glycerol-3-phosphate dehydrogenase GfdA thatcatalyzes the reduction of dihydroxyacetone phosphate (DHAP) to G3P rescued phenotypes of the glcA null mutant to H2O2. Therefore, the present study suggests that GlcA-involved G3P synthesis participates in oxidative stress tolerance of A. fumigatus via regulating the cellular ROS level.


Assuntos
Aspergillus fumigatus/metabolismo , Glicerol Quinase/metabolismo , Glicerolfosfato Desidrogenase/metabolismo , Estresse Oxidativo/fisiologia , Aspergillus fumigatus/genética , Glucose/metabolismo , Glicerol/metabolismo , Glicerol Quinase/fisiologia , Glicerolfosfato Desidrogenase/biossíntese , Glicerofosfatos , Peróxido de Hidrogênio/metabolismo , Redes e Vias Metabólicas , Mitocôndrias/metabolismo , Oxirredução , Fenótipo , Fosfatos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
Planta ; 253(2): 46, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33484359

RESUMO

MAIN CONCLUSION: This study identified a new bHLHm1 transcription factor MdSAT1 which functioned in mediating tolerance to salt and drought resistance. Changes in the expression of stress-related genes play crucial roles in response to environmental stress. Basic helix-loop-helix (bHLH) proteins are the largest superfamily of transcription factors and a large number of bHLH proteins function in plant responses to abiotic stresses. We identified a new bHLHm1 transcription factor from apple and named it MdSAT1. ß-Glucuronidase (GUS) staining showed that MdSAT1 expressed in various tissues with highly expressed in leaves. Promoter analysis revealed that MdSAT1 contained multiple response elements and its transcription was induced by several environmental cues, particularly salt and drought stresses. Overexpression of MdSAT1 in apple calli and Arabidopsis resulted in a phenotype of increased tolerance to salt and drought. Altering abscisic acid (ABA) treatment increased the sensitivity of MdSAT1-OE Arabidopsis to ABA, and heavy metal stress, osmotic stress, and ethylene did not participate in MdSAT1 mediated plant development. These findings reveal the abiotic stress functions of MdSAT1 and pave the way for further functional investigation.


Assuntos
Secas , Malus , Proteínas de Plantas , Estresse Fisiológico , Ácido Abscísico , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Salinidade , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Appl Environ Microbiol ; 87(4)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33257310

RESUMO

The electron donor cytochrome b5 (CybE/Cyb5) fuels the activity of the ergosterol biosynthesis-related P450 enzymes/P450s by providing electrons to P450s to promote ergosterol biosynthesis. Previous studies reported that lack of Aspergillus fumigatus (A. fumigatus) CybE reduces the proportion of ergosterol in total sterols and induces severe growth defects. However, the molecular characteristics of CybE and the underlying mechanism for CybE maintaining A. fumigatus growth remain poorly understood. Here, we found that CybE locates at the endoplasmic reticulum by its C-terminus with two transmembrane regions. Therefore, lack of the C-terminus of CybE is able to phenocopy a cybE deletion. Notably, cybE deletion reduced the accumulation of the sterol-rich plasma membrane domains (SRDs, the assembly platform of polarity factors/cell end markers and growth machinery) in hyphal tips and decreased membrane fluidity, which correspond to tardiness of hyphal extension and hypersensitivity to low temperature in cybE deletion mutant. Additionally, overexpressing another electron donor-heme-independent P450 reductase (CPR) significantly rescued growth defects and recovered SRD accumulation in deletion of cybE almost to the wild-type level, suggesting CybE maintaining the growth and deposition of SRDs in hyphal tips attributes to its nature as an electron donor. Protein pull-down assays revealed that CybE probably participates in metabolism and transfer of lipids, construction of cytoskeleton and mitochondria-associated energy metabolism to maintain the SRD accumulation in hyphal tips, membrane fluidity and hyphal extension. Findings in this study give a hint that inhibition of CybE may be an effective strategy for resisting the infection of the human pathogen A. fumigatus Importance Investigating the knowledge of the growth regulation in the human opportunistic pathogen A. fumigatus is conducive to design new antifungal approach. The electron donor cytochrome b5 (CybE) plays a crucial role in maintaining the normal growth of A. fumigatus, however, the potential mechanism remains elusive. Herein, we characterized the molecular features of CybE and found the C-terminus with two transmembrane domains are required for its ER localization and functions. In addition, we demonstrated that CprA, an electron donor-heme-independent P450 reductase, provides a reciprocal function for the missing cytochrome b5 protein-CybE in A. fumigatus CybE maintains the normal growth probably via supporting two crucial physiological processes, the SRD accumulation in hyphal tips and membrane fluidity. Therefore, our finding reveals the mechanisms underlying the regulatory effect of CybE on A. fumigatus growth and indicates that inhibition of CybE might be an effective approach for alleviating A. fumigatus infection.

9.
Sensors (Basel) ; 21(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34770561

RESUMO

For wireless sensor networks (WSN) with connection failure uncertainties, traditional minimum spanning trees are no longer a feasible option for selecting routes. Reliability should come first before cost since no one wants a network that cannot work most of the time. First, reliable route selection for WSNs with connection failure uncertainties is formulated by considering the top-k most reliable spanning trees (RST) from graphs with structural uncertainties. The reliable spanning trees are defined as a set of spanning trees with top reliabilities and limited tree weights based on the possible world model. Second, two tree-filtering algorithms are proposed: the k minimum spanning tree (KMST) based tree-filtering algorithm and the depth-first search (DFS) based tree-filtering algorithm. Tree-filtering strategy filters the candidate RSTs generated by tree enumeration with explicit weight thresholds and implicit reliability thresholds. Third, an innovative edge-filtering method is presented in which edge combinations that act as upper bounds for RST reliabilities are utilized to filter the RST candidates and to prune search spaces. Optimization strategies are also proposed for improving pruning capabilities further and for enhancing computations. Extensive experiments are conducted to show the effectiveness and efficiency of the proposed algorithms.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Algoritmos , Reprodutibilidade dos Testes , Incerteza
10.
Plant Physiol ; 172(3): 1973-1988, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27660166

RESUMO

Iron (Fe) homeostasis is crucial for plant growth and development. A network of basic helix-loop-helix (bHLH) transcription factors positively regulates Fe uptake during iron deficiency. However, their up-regulation or overexpression leads to Fe overload and reactive oxygen species generation, thereby damaging the plants. Here, we found that two BTB/TAZ proteins, MdBT1 and MdBT2, interact with the MbHLH104 protein in apple. In addition, the function of MdBT2 was characterized as a regulator of MdbHLH104 degradation via ubiquitination and the 26S proteasome pathway, thereby controlling the activity of plasma membrane H+-ATPases and the acquisition of iron. Furthermore, MdBT2 interacted with MdCUL3 proteins, which were required for the MdBT2-mediated ubiquitination modification of MdbHLH104 and its degradation. In sum, our findings demonstrate that MdBT proteins interact with MdCUL3 to bridge the formation of the MdBTsMdCUL3 complex, which negatively modulates the degradation of the MdbHLH104 protein in response to changes in Fe status to maintain iron homeostasis in plants.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Homeostase/efeitos dos fármacos , Ferro/farmacologia , Malus/metabolismo , Proteínas de Plantas/metabolismo , Ubiquitinação/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Ferro/metabolismo , Malus/efeitos dos fármacos , Malus/genética , Modelos Biológicos , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , ATPases Translocadoras de Prótons/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Rizosfera
11.
Plant Biotechnol J ; 14(7): 1633-45, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26801352

RESUMO

Fe deficiency is a widespread nutritional disorder in plants. The basic helix-loop-helix (bHLH) transcription factors (TFs), especially Ib subgroup bHLH TFs which are involved in iron uptake, have been identified. In this study, an IVc subgroup bHLH TF MdbHLH104 was identified and characterized as a key component in the response to Fe deficiency in apple. The overexpression of the MdbHLH104 gene noticeably increased the H(+) -ATPase activity under iron limitation conditions and the tolerance to Fe deficiency in transgenic apple plants and calli. Further investigation showed that MdbHLH104 proteins bonded directly to the promoter of the MdAHA8 gene, thereby positively regulating its expression, the plasma membrane (PM) H(+) -ATPase activity and Fe uptake. Similarly, MdbHLH104 directly modulated the expression of three Fe-responsive bHLH genes, MdbHLH38, MdbHLH39 and MdPYE. In addition, MdbHLH104 interacted with 5 other IVc subgroup bHLH proteins to coregulate the expression of the MdAHA8 gene, the activity of PM H(+) -ATPase and the content of Fe in apple calli. Therefore, MdbHLH104 acts together with other apple bHLH TFs to regulate Fe uptake by modulating the expression of the MdAHA8 gene and the activity of PM H(+) -ATPase in apple.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas , Ferro/metabolismo , Malus/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Membrana Celular/metabolismo , Malus/metabolismo , Redes e Vias Metabólicas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
12.
J Proteome Res ; 14(8): 3292-304, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26165356

RESUMO

Tubulin is known to undergo unique post-translational modifications (PTMs), such as detyrosination and polyglutamylation, particularly in the unstructured carboxy-terminal tails (CTTs). However, more conventional PTMs of tubulin and their roles in the regulation of microtubule properties and functions remain poorly defined. Here, we report the comprehensive profiling of tubulin phosphorylation, acetylation, ubiquitylation, and O-GlcNAcylation in HeLa cells with a proteomic approach. Our tubulin-targeted analysis has identified 80 residues bearing single or multiple conventional PTMs including 24 novel PTM sites not covered in previous global proteomic surveys. By using a series of PTM-deficient or PTM-mimicking mutants, we further find that tubulin phosphorylation and acetylation play important roles in the control of microtubule assembly and stability. In addition, these tubulin PTMs have distinct effects on the retrograde transport of adenoviruses along microtubules. These findings thus enlarge the repertoire of tubulin PTMs and foster our understanding of their versatile roles in the regulation of microtubule dynamics and cellular functions.


Assuntos
Microtúbulos/metabolismo , Processamento de Proteína Pós-Traducional , Proteômica/métodos , Tubulina (Proteína)/metabolismo , Acetilação , Sequência de Aminoácidos , Sítios de Ligação/genética , Cromatografia Líquida , Glicosilação , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Immunoblotting , Espectrometria de Massas , Microscopia de Fluorescência , Microtúbulos/genética , Modelos Moleculares , Dados de Sequência Molecular , Fosforilação , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Tubulina (Proteína)/química , Tubulina (Proteína)/genética , Ubiquitinação
13.
Nat Commun ; 15(1): 2375, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490985

RESUMO

There is interest in developing sustainable materials displaying circularly polarized room-temperature phosphorescence, which have been scarcely reported. Here, we introduce biobased thin films exhibiting circularly polarized luminescence with simultaneous room-temperature phosphorescence. For this purpose, phosphorescence-active lignosulfonate biomolecules are co-assembled with cellulose nanocrystals in a chiral construct. The lignosulfonate is shown to capture the chirality generated by cellulose nanocrystals within the films, emitting circularly polarized phosphorescence with a 0.21 dissymmetry factor and 103 ms phosphorescence lifetime. By contrast with most organic phosphorescence materials, this chiral-phosphorescent system possesses phosphorescence stability, with no significant recession under extreme chemical environments. Meanwhile, the luminescent films resist water and humid environments but are fully biodegradable (16 days) in soil conditions. The introduced bio-based, environmentally-friendly circularly polarized phosphorescence system is expected to open many opportunities, as demonstrated here for information processing and anti-counterfeiting.

14.
Nat Commun ; 13(1): 3887, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794103

RESUMO

The development of smart-responsive materials, in particular those with non-invasive, rapid responsive phosphorescence, is highly desirable but has rarely been described. Herein, we designed and prepared a series of molecular rotors containing a triazine core and three bromobiphenyl units: o-Br-TRZ, m-Br-TRZ, and p-Br-TRZ. The bromine and triazine moieties serve as room temperature phosphorescence-active units, and the bromobiphenyl units serve as rotors to drive intramolecular rotation. When irradiated with strong ultraviolet photoirradiation, intramolecular rotations of o-Br-TRZ, m-Br-TRZ, and p-Br-TRZ increase, successively resulting in a photothermal effect via molecular motions. Impressively, the photothermal temperature attained by p-Br-TRZ is as high as 102 °C, and synchronously triggers its phosphorescence due to the ordered molecular arrangement after molecular motion. The thermal effect is expected to be important for triggering efficient phosphorescence, and the photon input for providing a precise and non-invasive stimulus. Such sequential photo-thermo-phosphorescence conversion is anticipated to unlock a new stimulus-responsive phosphorescence material without chemicals invasion.

15.
mBio ; 12(6): e0300721, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34781745

RESUMO

The life cycle of filamentous fungi generally comprises hyphal growth and asexual reproduction. Both growth and propagation processes are critical for invasion growth, spore dissemination, and virulence in fungal pathogens and for the production of secondary metabolites or for biomass accumulation in industrial filamentous fungi. The CCAAT-binding complex (CBC) is a heterotrimeric transcription factor comprising three subunits, HapB, HapC, and HapE, and is highly conserved in fungi. Previous studies revealed that CBC regulates sterol metabolism by repressing several genes in the ergosterol biosynthetic pathway in the human fungal pathogen Aspergillus fumigatus. In the present study, we found dysfunction of CBC caused the abnormal asexual reproduction (conidiation) in submerged liquid culture. CBC suppresses the activation of the brlA gene in the central regulatory pathway for conidiation combined with its upstream regulators fluG, flbD, and flbC by binding to the 5'-CCAAT-3' motif within conidiation gene promoters, and lack of CBC member HapB results in the upregulation of these genes. Furthermore, when the expression of brlA or flbC is repressed, the submerged conidiation does not happen in the hapB mutant. Interestingly, deletion of HapB leads to enhanced transient cytosolic Ca2+ levels and activates conidiation-positive inducer Ca2+-CrzA modules to enhance submerged conidiation, demonstrating that CrzA works with CBC as a reverse regulator of fungal conidiation. To the best of our knowledge, the finding of this study is the first report for the molecular switch mechanism between vegetative hyphal growth and asexual development regulated by CBC, in concert with Ca2+-CrzA signaling in A. fumigatus. IMPORTANCE A precisely timed switch between vegetative hyphal growth and asexual development is a crucial process for the filamentous fungal long-term survival, dissemination, biomass production, and virulence. However, under the submerged culture condition, filamentous fungi would undergo constant vegetative growth whereas asexual conidiation rarely occurs. Knowledge about possible regulators is scarce, and how they could inhibit conidiation in liquid culture is poorly understood. Here, we demonstrated that the transcription factor heterotrimeric CBC dominantly maintains vegetative growth in liquid-submerged cultures by directly suppressing the conidiation-inductive signal. In contrast, calcium and the transcription factor CrzA, are positive inducers of conidiation. Our new insights into the CBC and Ca2+-CrzA regulatory system for transition control in the submerged conidiation of A. fumigatus may have broad repercussions for all filamentous fungi. Moreover, our elucidation of the molecular mechanism for submerged conidiation may support new strategies to precisely control vegetative growth and asexual conidiation in aspergilli used in industry.


Assuntos
Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/metabolismo , Fator de Ligação a CCAAT/metabolismo , Cálcio/metabolismo , Proteínas Fúngicas/metabolismo , Hifas/crescimento & desenvolvimento , Aspergillus fumigatus/genética , Fator de Ligação a CCAAT/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Hifas/genética , Hifas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Reprodução Assexuada , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo
16.
Virulence ; 12(1): 1091-1110, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33843471

RESUMO

In eukaryotes, calcium not only is an essential mineral nutrient but also serves as an intracellular second messenger that is necessary for many physiological processes. Previous studies showed that the protein phosphatase-calcineurin protects fungi from toxicity caused by the extracellular calcium; however, little is known about how calcineurin mediates the cellular physiology process for this function. In this study, by monitoring intracellular calcium, particularly by tracking vacuolar calcium dynamics in living cells through a novel procedure using modified aequorin, we found that calcineurin dysfunction systematically caused abnormal intracellular calcium homeostasis in cytosol, mitochondria, and vacuole, leading to drastic autophagy, global organelle fragmentation accompanied with the increased expression of cell death-related enzymes, and cell death upon extracellular calcium stimuli. Notably, all detectable defective phenotypes seen with calcineurin mutants can be significantly suppressed by alleviating a cytosolic calcium overload or increasing vacuolar calcium storage capacity, suggesting toxicity of exogenous calcium to calcineurin mutants is tightly associated with abnormal cytosolic calcium accumulation and vacuolar calcium storage capacity deficiency. Our findings provide insights into how the original recognized antifungal drug target-calcineurin regulates intracellular calcium homeostasis for cell survival and may have important implications for antifungal therapy and clinical drug administration.


Assuntos
Antifúngicos , Calcineurina , Cálcio/metabolismo , Preparações Farmacêuticas , Fungos , Homeostase/fisiologia , Mitocôndrias
17.
Microbiologyopen ; 10(6): e1249, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34964293

RESUMO

In fungal pathogens, the transcription factor SrbA (a sterol regulatory element-binding protein, SREBP) and CBC (CCAAT binding complex) have been reported to regulate azole resistance by competitively binding the TR34 region (34 mer) in the promoter of the drug target gene, erg11A. However, current knowledge about how the SrbA and CBC coordinately mediate erg11A expression remains limited. In this study, we uncovered a novel relationship between HapB (a subunit of CBC) and SrbA in which deletion of hapB significantly prolongs the nuclear retention of SrbA by increasing its expression and cleavage under azole treatment conditions, thereby enhancing Erg11A expression for drug resistance. Furthermore, we verified that loss of HapB significantly induces the expression of the rhomboid protease RbdB, Dsc ubiquitin E3 ligase complex, and signal peptide peptidase SppA, which are required for the cleavage of SrbA, suggesting that HapB acts as a repressor for these genes which contribute to the activation of SrbA by proteolytic cleavage. Together, our study reveals that CBC functions not only to compete with SrbA for binding to erg11A promoter region but also to affect SrbA expression, cleavage, and translocation to nuclei for the function, which ultimately regulate Erg11A expression and azole resistance.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Azóis/farmacologia , Fator de Ligação a CCAAT/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Fator de Ligação a CCAAT/genética , Família 51 do Citocromo P450/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Testes de Sensibilidade Microbiana , Mutação , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
18.
Hortic Res ; 8(1): 22, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33518703

RESUMO

Nitrogen is an important factor that affects plant anthocyanin accumulation. In apple, the nitrate-responsive BTB/TAZ protein MdBT2 negatively regulates anthocyanin biosynthesis. In this study, we found that MdBT2 undergoes posttranslational modifications in response to nitrate deficiency. Yeast two-hybrid, protein pull-down, and bimolecular fluorescence complementation (BiFC) assays showed that MdBT2 interacts with MdGRF11, a 14-3-3 protein; 14-3-3 proteins compose a family of highly conserved phosphopeptide-binding proteins involved in multiple physiological and biological processes. The interaction of MdGRF11 negatively regulated the stability of the MdBT2 protein via a 26S proteasome-dependent pathway, which increased the abundance of MdMYB1 proteins to activate the expression of anthocyanin biosynthesis-related genes. Taken together, the results demonstrate the critical role of 14-3-3 proteins in the regulation of nitrate deficiency-induced anthocyanin accumulation. Our results provide a novel avenue to elucidate the mechanism underlying the induction of anthocyanin biosynthesis in response to nitrate deficiency.

19.
Mol Plant ; 14(9): 1454-1471, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34022440

RESUMO

Although taste is an important aspect of fruit quality, an understanding of its genetic control remains elusive in apple and other fruit crops. In this study, we conducted genomic sequence analysis of 497 Malus accessions and revealed erosion of genetic diversity caused by apple breeding and possible independent domestication events of dessert and cider apples. Signatures of selection for fruit acidity and size, but not for fruit sugar content, were detected during the processes of both domestication and improvement. Furthermore, we found that single mutations in major genes affecting fruit taste, including Ma1, MdTDT, and MdSOT2, dramatically decrease malate, citrate, and sorbitol accumulation, respectively, and correspond to important domestication events. Interestingly, Ma1 was identified to have pleiotropic effects on both organic acid content and sugar:acid ratio, suggesting that it plays a vital role in determining fruit taste. Fruit taste is unlikely to have been negatively affected by linkage drag associated with selection for larger fruit that resulted from the pyramiding of multiple genes with minor effects on fruit size. Collectively, our study provides new insights into the genetic basis of fruit quality and its evolutionary roadmap during apple domestication, pinpointing several candidate genes for genetic manipulation of fruit taste in apple.


Assuntos
Frutas/genética , Malatos/metabolismo , Malus/genética , Mutação , Paladar , Evolução Biológica , Domesticação , Genes de Plantas/genética
20.
Chemosphere ; 253: 126628, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464771

RESUMO

Superfine powdered activated carbon (S-PAC) is an adsorbent material with the promise of properties that allow for rapid adsorption of small molecule contaminants. To explore the potential for rapid adsorption among varying activated carbon types, seven commercially available activated carbons were obtained and pulverized to produce S-PAC particles less than 1 µm in diameter. The carbons were chosen to include several types of common carbons produced from coal precursors as well as a wood-based carbon and a coconut shell-based carbon. In this study, the S-PACs and their parent PACs were tested for the adsorption of three aromatic compounds-2-phenylphenol, biphenyl, and phenanthrene-with and without the presence of natural organic matter (NOM). Adsorption rates were increased for adsorption onto S-PAC as compared to PAC in all trials without NOM and in most trials with NOM. Faster adsorption onto S-PAC was found to be a result of a smaller particle size, lower surface oxygen content, larger pore diameters, and neutral pHPZC. Adsorption of a planar compound, phenanthrene, increased the most between PAC and S-PAC, while adsorption of 2-phenylphenol, a nonplanar compound, was impacted the least. Phenanthrene additionally was minimally impacted by the presence of NOM while 2-phenylphenol adsorption declined severely in the presence of NOM.


Assuntos
Adsorção , Carvão Vegetal/química , Compostos Orgânicos/química , Hidrocarbonetos Aromáticos/química , Concentração de Íons de Hidrogênio , Cinética , Conformação Molecular , Tamanho da Partícula
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