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1.
J Agric Food Chem ; 69(39): 11626-11636, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34554747

RESUMO

Crocetin, a high-value apocarotenoid in saffron, is widely applied to the fields of food and medicine. However, the existing method of obtaining crocetin through large-scale cultivation is far from meeting the market demand. Microbial synthesis of crocetin is a potential alternative to traditional resources, and it is found that carotenoid cleavage dioxygenase (CCD) is the critical enzyme to synthesize crocetin. So, in this study, we used "hybrid-tunnel" engineering to obtain variants of Crocus sativus-derived CsCCD2, essential for zeaxanthin conversion into crocetin, with a broader substrate specificity and higher catalytic efficiency. Variants including S323A, with a lower charge bias and a larger tunnel size than the wild-type, showed a 5-fold higher crocetin titer in yeast-based fermentations. S323A could also convert the ß-carotene substrate to crocetin dialdehyde and exhibited a 12.83-fold greater catalytic efficiency (kcat/Km) toward zeaxanthin than the wild-type in vitro. This strategy enabled the production of 107 mg/L crocetin in 5 L fed-batch fermentation, higher than that previously reported. Our findings demonstrate that engineering access tunnels to expand the substrate profile by in silico protein design represents a viable strategy to refine the catalytic properties of enzymes across a range of applications.


Assuntos
Crocus , Dioxigenases , Carotenoides , Vitamina A/análogos & derivados , Zeaxantinas
2.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576030

RESUMO

Clinical evidence suggests that conventional cardiovascular disease (CVD) risk factors cannot explain all CVD incidences. Recent studies have shown that telomere attrition, clonal hematopoiesis of indeterminate potential (CHIP), and atherosclerosis (telomere-CHIP-atherosclerosis, TCA) evolve to play a crucial role in CVD. Telomere dynamics and telomerase have an important relationship with age-related CVD. Telomere attrition is associated with CHIP. CHIP is commonly observed in elderly patients. It is characterized by an increase in blood cell clones with somatic mutations, resulting in an increased risk of hematological cancer and atherosclerotic CVD. The most common gene mutations are DNA methyltransferase 3 alpha (DNMT3A), Tet methylcytosine dioxygenase 2 (TET2), and additional sex combs-like 1 (ASXL1). Telomeres, CHIP, and atherosclerosis increase chronic inflammation and proinflammatory cytokine expression. Currently, their epidemiology and detailed mechanisms related to the TCA axis remain incompletely understood. In this article, we reviewed recent research results regarding the development of telomeres and CHIP and their relationship with atherosclerotic CVD.


Assuntos
Aterosclerose/genética , Doenças Cardiovasculares/genética , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Proteínas Repressoras/genética , Envelhecimento/genética , Envelhecimento/patologia , Aterosclerose/patologia , Doenças Cardiovasculares/patologia , Evolução Clonal/genética , Hematopoiese Clonal/genética , Humanos , Mutação/genética , Telômero/genética
3.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445508

RESUMO

This study investigated the effects of root-restriction cultivation on the root architecture, endogenous strigolactone (SL) content, and SL-related genes expression in grapevine (Vitis vinifera L.). In addition, we clarified the effects of synthetic SL analog GR24 application on grapevine roots to explore the role of SLs in their development. The results showed that the root architecture changed significantly under root-restriction cultivation. At 40 days after transplantation (DAT), the contents of two types of SLs in roots under root restriction were both significantly lower than that in roots of the control. SL content was significantly positively correlated with the expression levels of VvCCD8 and VvD27, indicating that they play vital roles in SLs synthesis. After GR24 treatment for 20 days, the root length was significantly shorter than in the control. A low concentration (0.1 µM) of GR24 significantly reduced the root diameter and increased the fine-root density, while a high concentration (10 µM) of GR24 significantly reduced the lateral root (LR) length and increased the LR density. Concomitantly, GR24 (0.1 µM) reduced endogenous SL content. After GR24 treatment for 5 days, the total content of two tested SLs was highly positively correlated with the expression levels of VvDAD2, whereas it was highly negatively correlated with VvSMAXL4 at 20 days after GR24 treatment. This study helps to clarify the internal mechanism of root-restriction cultivation affecting the changes in grapevine root architecture, as well as further explore the important role of SLs in the growth of grapevine roots in response to root-restriction treatment.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Lactonas/farmacologia , Proteínas de Plantas/genética , Vitis/crescimento & desenvolvimento , Dioxigenases/genética , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Vitis/efeitos dos fármacos , Vitis/genética
4.
Theranostics ; 11(16): 7970-7983, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335974

RESUMO

The novel ß-coronavirus, SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19), has infected more than 177 million people and resulted in 3.84 million death worldwide. Recent epidemiological studies suggested that some environmental factors, such as air pollution, might be the important contributors to the mortality of COVID-19. However, how environmental exposure enhances the severity of COVID-19 remains to be fully understood. In the present report, we provided evidence showing that mdig, a previously reported environmentally-induced oncogene that antagonizes repressive trimethylation of histone proteins, is an important regulator for SARS-CoV-2 receptors neuropilin-1 (NRP1) and NRP2, cathepsins, glycan metabolism and inflammation, key determinants for viral infection and cytokine storm of the patients. Depletion of mdig in bronchial epithelial cells by CRISPR-Cas-9 gene editing resulted in a decreased expression of NRP1, NRP2, cathepsins, and genes involved in protein glycosylation and inflammation, largely due to a substantial enrichment of lysine 9 and/or lysine 27 trimethylation of histone H3 (H3K9me3/H3K27me3) on these genes as determined by ChIP-seq. Meanwhile, we also validated that environmental factor arsenic is able to induce mdig, NRP1 and NRP2, and genetic disruption of mdig lowered expression of NRP1 and NRP2. Furthermore, mdig may coordinate with the Neanderthal variants linked to an elevated mortality of COVID-19. These data, thus, suggest that mdig is a key mediator for the severity of COVID-19 in response to environmental exposure and targeting mdig may be the one of the effective strategies in ameliorating the symptom and reducing the mortality of COVID-19.


Assuntos
COVID-19/metabolismo , COVID-19/virologia , Dioxigenases/metabolismo , Histona Desmetilases/metabolismo , Neuropilina-1/metabolismo , Proteínas Nucleares/metabolismo , Polissacarídeos/metabolismo , SARS-CoV-2/metabolismo , Células Epiteliais Alveolares/metabolismo , Animais , COVID-19/epidemiologia , Catepsinas/metabolismo , Linhagem Celular , Células Cultivadas , Dioxigenases/biossíntese , Dioxigenases/genética , Exposição Ambiental , Histona Desmetilases/biossíntese , Histona Desmetilases/genética , Histonas/metabolismo , Humanos , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Pandemias , Ratos , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo
5.
Int J Mol Sci ; 22(16)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34445457

RESUMO

Strigolactones (SLs) regulate plant shoot development by inhibiting axillary bud growth and branching. However, the role of SLs in wintersweet (Chimonanthus praecox) shoot branching remains unknown. Here, we identified and isolated two wintersweet genes, CCD7 and CCD8, involved in the SL biosynthetic pathway. Quantitative real-time PCR revealed that CpCCD7 and CpCCD8 were down-regulated in wintersweet during branching. When new shoots were formed, expression levels of CpCCD7 and CpCCD8 were almost the same as the control (un-decapitation). CpCCD7 was expressed in all tissues, with the highest expression in shoot tips and roots, while CpCCD8 showed the highest expression in roots. Both CpCCD7 and CpCCD8 localized to chloroplasts in Arabidopsis. CpCCD7 and CpCCD8 overexpression restored the phenotypes of branching mutant max3-9 and max4-1, respectively. CpCCD7 overexpression reduced the rosette branch number, whereas CpCCD8 overexpression lines showed no phenotypic differences compared with wild-type plants. Additionally, the expression of AtBRC1 was significantly up-regulated in transgenic lines, indicating that two CpCCD genes functioned similarly to the homologous genes of the Arabidopsis. Overall, our study demonstrates that CpCCD7 and CpCCD8 exhibit conserved functions in the CCD pathway, which controls shoot development in wintersweet. This research provides a molecular and theoretical basis for further understanding branch development in wintersweet.


Assuntos
Arabidopsis , Calycanthaceae/genética , Dioxigenases , Genes de Plantas , Proteínas de Plantas , Raízes de Plantas , Plantas Geneticamente Modificadas , Arabidopsis/enzimologia , Arabidopsis/genética , Calycanthaceae/enzimologia , Dioxigenases/biossíntese , Dioxigenases/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética
6.
Chemistry ; 27(55): 13793-13806, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34310770

RESUMO

Thiol dioxygenases are important enzymes for human health; they are involved in the detoxification and catabolism of toxic thiol-containing natural products such as cysteine. As such, these enzymes have relevance to the development of Alzheimer's and Parkinson's diseases in the brain. Recent crystal structure coordinates of cysteine and 3-mercaptopropionate dioxygenase (CDO and MDO) showed major differences in the second-coordination spheres of the two enzymes. To understand the difference in activity between these two analogous enzymes, we created large, active-site cluster models. We show that CDO and MDO have different iron(III)-superoxo-bound structures due to differences in ligand coordination. Furthermore, our studies show that the differences in the second-coordination sphere and particularly the position of a positively charged Arg residue results in changes in substrate positioning, mobility and enzymatic turnover. Furthermore, the substrate scope of MDO is explored with cysteinate and 2-mercaptosuccinic acid and their reactivity is predicted.


Assuntos
Dioxigenases , Domínio Catalítico , Cisteína , Cisteína Dioxigenase/metabolismo , Compostos Férricos , Humanos
7.
EMBO Rep ; 22(8): e52716, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34288360

RESUMO

TET methylcytosine dioxygenases are essential for the stability and function of regulatory T cells (Treg cells), which maintain immune homeostasis and self-tolerance and express the lineage-determining transcription factor Foxp3. Here, we use whole-genome analyses to show that the transcriptional program and epigenetic features (DNA modification, chromatin accessibility) of Treg cells are attenuated in the absence of Tet2 and Tet3. Conversely, the addition of the TET activator vitamin C during TGFß-induced iTreg cell differentiation in vitro potentiates the expression of Treg signature genes and alters the epigenetic landscape to better resemble that of Treg cells generated in vivo. Vitamin C enhances IL-2 responsiveness in iTreg cells by increasing IL2Rα expression, STAT5 phosphorylation, and STAT5 binding, mimicking the IL-2/STAT5 dependence of Treg cells generated in vivo. In summary, TET proteins play essential roles in maintaining Treg molecular features and promoting their dependence on IL-2. TET activity during endogenous Treg development and potentiation of TET activity by vitamin C during iTreg differentiation are necessary to maintain the transcriptional and epigenetic features of Treg cells.


Assuntos
Dioxigenases , Linfócitos T Reguladores , Diferenciação Celular/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/metabolismo
8.
Nat Commun ; 12(1): 4100, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215750

RESUMO

Tet3 is the main α-ketoglutarate (αKG)-dependent dioxygenase in neurons that converts 5-methyl-dC into 5-hydroxymethyl-dC and further on to 5-formyl- and 5-carboxy-dC. Neurons possess high levels of 5-hydroxymethyl-dC that further increase during neural activity to establish transcriptional plasticity required for learning and memory functions. How αKG, which is mainly generated in mitochondria as an intermediate of the tricarboxylic acid cycle, is made available in the nucleus has remained an unresolved question in the connection between metabolism and epigenetics. We show that in neurons the mitochondrial enzyme glutamate dehydrogenase, which converts glutamate into αKG in an NAD+-dependent manner, is redirected to the nucleus by the αKG-consumer protein Tet3, suggesting on-site production of αKG. Further, glutamate dehydrogenase has a stimulatory effect on Tet3 demethylation activity in neurons, and neuronal activation increases the levels of αKG. Overall, the glutamate dehydrogenase-Tet3 interaction might have a role in epigenetic changes during neural plasticity.


Assuntos
Núcleo Celular/enzimologia , Núcleo Celular/metabolismo , Dioxigenases/metabolismo , Glutamato Desidrogenase/metabolismo , Ácidos Cetoglutáricos/metabolismo , Neurônios/metabolismo , Animais , Encéfalo/metabolismo , Ciclo do Ácido Cítrico , Dioxigenases/genética , Epigenômica , Expressão Gênica , Glutamato Desidrogenase/genética , Ácido Glutâmico/metabolismo , Células HEK293 , Humanos , Complexo Cetoglutarato Desidrogenase/metabolismo , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Plasticidade Neuronal
9.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207287

RESUMO

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.


Assuntos
Ácido Abscísico/metabolismo , Agaricales/patogenicidade , Proteínas Fúngicas/genética , Gastrodia/microbiologia , Lignina/metabolismo , Proteínas de Plantas/genética , Agaricales/genética , Agaricales/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas Fúngicas/metabolismo , Gastrodia/genética , Gastrodia/crescimento & desenvolvimento , Gastrodia/metabolismo , Germinação , Lacase/genética , Lacase/metabolismo , Lignina/genética , Peroxidases/genética , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Simbiose , Transcriptoma
10.
Free Radic Biol Med ; 172: 578-589, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34242792

RESUMO

Acetaminophen (APAP) is the leading cause of acute liver failure (ALF), which is characterized by GSH depletion, oxidative stress and mitochondrial dysfunction. However, the specific mechanism of APAP-induced ALF remains to be clarified. In this study, we demonstrated that indoleamine 2,3-dioxygenase 1 (IDO1) aggravated APAP-induced ALF associated with excess lipid peroxidation, which was reversed by lipid peroxidation inhibitor (ferrostatin-1). Meanwhile, IDO1 deficiency effectively decreased the accumulation of reactive nitrogen species. Additionally, IDO1 deficiency prevented against APAP-induced liver injury through suppressing the activation of macrophages, thereby reduced their iron uptake and export, eventually reduced iron accumulation in hepatocytes through transferrin and transferrin receptor axis. In summary, our study confirmed that APAP-induced IDO1 aggravated ALF by triggering excess oxidative and nitrative stress and iron accumulation in liver. These results offer new insights for the clinical treatment of ALF or iron-dysregulated liver diseases in the future.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Dioxigenases , Falência Hepática Aguda , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Dioxigenases/metabolismo , Hepatócitos , Ferro/metabolismo , Fígado/metabolismo , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo
11.
J Hazard Mater ; 419: 126428, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34171665

RESUMO

Chlorinated aromatic compounds are a serious environmental concern because of their widespread occurrence throughout the environment. Although several microorganisms have evolved to gain the ability to degrade chlorinated aromatic compounds and use them as carbon sources, they still cannot meet the diverse needs of pollution remediation. In this study, the degradation pathways for 3-chlorocatechol (3CC) and 4-chlorocatechol (4CC) were successfully reconstructed by the optimization, synthesis, and assembly of functional genes from different strains. The addition of a 13C-labeled substrate and functional analysis of different metabolic modules confirmed that the genetically engineered strains can metabolize chlorocatechol similar to naturally degrading strains. The strain containing either of these artificial pathways can degrade catechol, 3CC, and 4CC completely, although differences in the degradation efficiency may be noted. Proteomic analysis and scanning electron microscopy observation showed that 3CC and 4CC have toxic effects on Escherichia coli, but the engineered bacteria can significantly eliminate these inhibitory effects. As core metabolic pathways for the degradation of chloroaromatics, the two chlorocatechol degradation pathways constructed in this study can be used to construct pollution remediation-engineered bacteria, and the related technologies may be applied to construct complete degradation pathways for complex organic hazardous materials.


Assuntos
Dioxigenases , Escherichia coli , Biodegradação Ambiental , Catecóis , Escherichia coli/genética , Proteômica
12.
Theranostics ; 11(14): 6717-6734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093849

RESUMO

Rationale: Osteoporotic patients suffer symptoms of excessive osteoclastogenesis and impaired osteogenesis, resulting in a great challenge to treat osteoporosis-related bone defects. Based on the positive effect of rare earth elements on bone metabolism and bone regeneration, we try to prove the hypothesis that the La3+ dopants in lanthanum-substituted MgAl layered double hydroxide (La-LDH) nanohybrid scaffolds simultaneously activate osteogenesis and inhibit osteoclastogenesis. Methods: A freeze-drying technology was employed to construct La-LDH nanohybrid scaffolds. The in vitro osteogenic and anti-osteoclastogenic activities of La-LDH nanohybrid scaffolds were evaluated by using ovariectomized rat bone marrow stromal cells (rBMSCs-OVX) and bone marrow-derived macrophages (BMMs) as cell models. The in vivo bone regeneration ability of the scaffolds was investigated by using critical-size calvarial bone defect model of OVX rats. Results: La-LDH nanohybrid scaffolds exhibited three-dimensional macroporous structure, and La-LDH nanoplates arranged perpendicularly on chitosan organic matrix. The La3+ dopants in the scaffolds promote proliferation and osteogenic differentiation of rBMSCs-OVX by activating Wnt/ß-catenin pathway, leading to high expression of ALP, Runx-2, COL-1 and OCN genes. Moreover, La-LDH scaffolds significantly suppressed RANKL-induced osteoclastogenesis by inhibiting NF-κB signaling pathway. As compared with the scaffolds without La3+ dopants, La-LDH scaffolds provided more favourable microenvironment to induce new bone in-growth along macroporous channels. Conclusion: La-LDH nanohybrid scaffolds possessed the bi-directional regulation functions on osteogenesis and osteoclastogenesis for osteoporotic bone regeneration. The modification of La3+ dopants in bone scaffolds provides a novel strategy for osteoporosis-related bone defect healing.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Lantânio/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Tecidos Suporte/química , Animais , Regeneração Óssea/genética , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dioxigenases/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Lantânio/química , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , NF-kappa B/metabolismo , Nanoestruturas/ultraestrutura , Osteocalcina/metabolismo , Osteogênese/genética , Osteoporose/metabolismo , Ligante RANK/farmacologia , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
13.
Chemosphere ; 282: 130975, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34111638

RESUMO

Even though the genetic attributes suggest presence of multiple degradation pathways, most of rhodococci are known to transform PCBs only via regular biphenyl (bph) pathway. Using GC-MS analysis, we monitored products formed during transformation of 2,4,4'-trichlorobiphenyl (PCB-28), 2,2',5,5'-tetrachlorobiphenyl (PCB-52) and 2,4,3'-trichlorobiphenyl (PCB-25) by previously characterized PCB-degrading rhodococci Z6, T6, R2, and Z57, with the aim to explore their metabolic pleiotropy in PCB transformations. A striking number of different transformation products (TPs) carrying a phenyl ring as a substituent, both those generated as a part of the bph pathway and an array of unexpected TPs, implied a curious transformation ability. We hypothesized that studied rhodococcal isolates, besides the regular one, use at least two alternative pathways for PCB transformation, including the pathway leading to acetophenone formation (via 3,4 (4,5) dioxygenase attack on the molecule), and a third sideway pathway that includes stepwise oxidative decarboxylation of the aliphatic side chain of the 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate. Structure of the identified chlorinated benzoic acids and acetophenones allowed us to hypothesize that the first two pathways were the outcome of a ring-hydroxylating dioxygenase with the ability to attack both the 2,3 (5,6) and the 3,4 (4,5) positions of the biphenyl ring as well as dechlorination activity at both, -ortho and -para positions. We propose that several TPs produced by the bph pathway could have caused the triggering of the third sideway pathway. In conclusion, this study proposed ability of rhodococci to use different strategies in PCB transformation, which allows them to circumvent potential negative aspect of TPs on the overall transformation pathway.


Assuntos
Dioxigenases , Bifenilos Policlorados , Rhodococcus , Biodegradação Ambiental
14.
Cell Death Dis ; 12(6): 535, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035232

RESUMO

Tet dioxygenases are responsible for the active DNA demethylation. The functions of Tet proteins in muscle regeneration have not been well characterized. Here we find that Tet2, but not Tet1 and Tet3, is specifically required for muscle regeneration in vivo. Loss of Tet2 leads to severe muscle regeneration defects. Further analysis indicates that Tet2 regulates myoblast differentiation and fusion. Tet2 activates transcription of the key differentiation modulator Myogenin (MyoG) by actively demethylating its enhancer region. Re-expressing of MyoG in Tet2 KO myoblasts rescues the differentiation and fusion defects. Further mechanistic analysis reveals that Tet2 enhances MyoD binding by demethylating the flanking CpG sites of E boxes to facilitate the recruitment of active histone modifications and increase chromatin accessibility and activate its transcription. These findings shed new lights on DNA methylation and pioneer transcription factor activity regulation.


Assuntos
Dioxigenases/fisiologia , Músculos/fisiologia , Regeneração/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , Dioxigenases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mioblastos/metabolismo , Mioblastos/fisiologia , Miogenina/genética , Miogenina/metabolismo
15.
PLoS One ; 16(5): e0250349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33961636

RESUMO

Gibberellin-dioxygenases genes plays important roles in the regulating plant development. However, Gibberellin-dioxygenases genes are rarely reported in maize, especially response to gibberellin (GA). In present study, 27 Gibberellin-dioxygenases genes were identified in the maize and they were classified into seven subfamilies (I-VII) based on phylogenetic analysis. This result was also further confirmed by their gene structure and conserved motif characteristics. And gibberellin-dioxygenases genes only occurred segmental duplication that occurs most frequently in plants. Furthermore, the gibberellin-dioxygenases genes showed different tissue expression pattern in different tissues and most of the gibberellin-dioxygenases genes showed tissue specific expression. Moreover, almost all the gibberellin-dioxygenases genes were significantly elevated in response to GA except for ZmGA2ox2 and ZmGA20ox10 of 15 gibberellin-dioxygenases genes normally expressed in leaves while 10 and 11 gibberellin-dioxygenases genes showed up and down regulated under GA treatment than that under normal condition in leaf sheath. In addition, we found that ZmGA2ox1, ZmGA2ox4, ZmGA20ox7, ZmGA3ox1 and ZmGA3ox3 might be potential genes for regulating balance of GAs which play essential roles in plant development. These findings will increase our understanding of Gibberellin-dioxygenases gene family in response to GA and will provide a solid base for further functional characterization of Gibberellin-dioxygenases genes in maize.


Assuntos
Dioxigenases/genética , Genômica , Giberelinas/metabolismo , Zea mays/genética , Regulação da Expressão Gênica de Plantas , Filogenia , Zea mays/metabolismo
16.
Arch Microbiol ; 203(7): 4101-4112, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34057546

RESUMO

Para-toluic acid, a major pollutant in industrial wastewater, is hazardous to human health. It has been demonstrated that Gram-negative bacteria are among the most effective degraders of para-toluic acid. In this study, the ability of Comamonas testosteroni strain 3a2, isolated from a petrochemical industry wastewater, to degrade para-toluic acid was investigated. The effect of different carbon (glucose and ethylene glycol) and nitrogen sources (urea, yeast extract, peptone, NaNO3, NH4NO3) on the biodegradation of para-toluic acid by the isolate 3a2 was evaluated. Furthermore, ring hydroxylating dioxygenase genes were amplified by PCR and their expression was evaluated during the biodegradation of para-toluic acid. The results indicated that strain 3a2 was able to degrade up to 1000 mg/L of para-toluic acid after 14 h. The highest degradation yield was recorded in the presence of yeast extract as nitrogen source. However, the formation of terephthalic acid and phthalic acid was noted during para-toluic acid degradation by the isolate 3a2. Toluate 1,2-dioxygenase, terephthalate 1,2 dioxygenase, and phthalate 4,5 dioxygenase genes were detected in the genomic DNA of 3a2. The induction of ring hydroxylating dioxygenase genes was proportional to the concentration of each hydrocarbon. This study showed that the isolate 3a2 can produce terephthalate and phthalate during the para-toluic acid biodegradation, which were also degraded after 24 h.


Assuntos
Comamonas testosteroni , Dioxigenases , Poluentes Ambientais , Biodegradação Ambiental , Comamonas testosteroni/enzimologia , Comamonas testosteroni/genética , Dioxigenases/genética , Poluentes Ambientais/metabolismo , Ácidos Ftálicos/metabolismo
17.
Cancer Sci ; 112(7): 2855-2869, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33970549

RESUMO

Ten-eleven translocation 1 (TET1) is an essential methylcytosine dioxygenase of the DNA demethylation pathway. Despite its dysregulation being known to occur in human cancer, the role of TET1 remains poorly understood. In this study, we report that TET1 promotes cell growth in human liver cancer. The transcriptome analysis of 68 clinical liver samples revealed a subgroup of TET1-upregulated hepatocellular carcinoma (HCC), demonstrating hepatoblast-like gene expression signatures. We performed comprehensive cytosine methylation and hydroxymethylation (5-hmC) profiling and found that 5-hmC was aberrantly deposited preferentially in active enhancers. TET1 knockdown in hepatoma cell lines decreased hmC deposition with cell growth suppression. HMGA2 was highly expressed in a TET1high subgroup of HCC, associated with the hyperhydroxymethylation of its intronic region, marked as histone H3K4-monomethylated, where the H3K27-acetylated active enhancer chromatin state induced interactions with its promoter. Collectively, our findings point to a novel type of epigenetic dysregulation, methylcytosine dioxygenase TET1, which promotes cell proliferation via the ectopic enhancer of its oncogenic targets, HMGA2, in hepatoblast-like HCC.


Assuntos
Proteína HMGA2/genética , Neoplasias Hepáticas/genética , Oxigenases de Função Mista/genética , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Cromatina/genética , Citosina/metabolismo , Metilação de DNA , Dioxigenases/metabolismo , Epigênese Genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Proteína HMGA2/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Oxigenases de Função Mista/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Regulação para Cima
18.
Infect Genet Evol ; 92: 104888, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33933634

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) mediated Coronavirus disease-19 (COVID-19) has affected millions of individuals around all corners of the globe. Symptoms and severities of infection with this highly contagious virus vary among individuals and there is disparity in the number of COVID-19-related casualties across different ethnic groups. The primary receptor for SARS-CoV-2 entry into the host cells is angiotensin-converting enzyme 2 (ACE2). Certain variants of ACE2 are known to be associated with COVID-19 comorbidities such as hypertension, cardiovascular complications, diabetes, chronic lung disease, etc. In this study, we looked into the geographic distribution of disease-associated variants of ACE2 as well as closely located PIR gene to explore any possible correlation with the disparities in COVID-19 severities and casualties across ethnic groups. Frequencies of the ACE2 variants associated with COVID-19 comorbidities are higher in the European and the admixed American populations. These variants are also present with stronger pairwise linkage disequilibrium (LD) in the European and the admixed American populations. On the other hand, the variants with protective role are more prevalent in the East and the South Asian populations. Strong pairwise LD exists among the activity modifying (modifier) variants of the PIR and ACE2 genes only in the European super-population. Absence of these PIR variants in the South Asian population may contribute to the overall lower COVID-19 case fatality rates (CFR) despite the dense population in this region.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , COVID-19/etnologia , COVID-19/genética , Dioxigenases/genética , SARS-CoV-2 , Alelos , COVID-19/epidemiologia , Predisposição Genética para Doença , Variação Genética , Saúde Global , Haplótipos , Humanos , Índice de Gravidade de Doença
19.
Artigo em Inglês | MEDLINE | ID: mdl-34019473

RESUMO

This work assessed the catabolic versatility of functional genes in hydrocarbon-utilizing bacteria obtained from the rhizosphere of plants harvested in aged polluted soil sites in Ogoni and their attenuation efficacy in a bioremediation study. Rhizosphere soil was enumerated for its hydrocarbon-utilizing bacteria. The bacteria were in-vitro screened and selected through the quantification of their total protein and specific intermediate pathway enzyme (catechol 2,3-dioxygenase) activity in the metabolism of hydrocarbon. Thereafter, agarose gel electrophoresis technique was deployed to profile the genome of the selected strains for catechol 2,3-dioxygenase (C23O), 1,2-alkane monooxygenase (alkB), and naphthalene dioxygenase (nahR). Four rhizobacterial isolates namely Pseudomonas fluorescens (A3), Achromobacter agilis (A4), Bacillus thuringiensis (D2), and Staphylococcus lentus (L1) were selected based on the presence of C23O, alkB, and nahR genes. The gel electrophoresis results showed an approximate molecular weight of 200 bp for alkB, 300 bp for C23O, and 400 bp for nahR. The gas chromatogram for residual total petroleum hydrocarbon (TPH) revealed mineralization of fractions C8-C17, phytane, C18-C30. TPH for in-vitro bioremediation of crude oil-polluted soil was observed to have an optimal reduction/loss of 97% within the 56th day of the investigation. This study has further revealed that the microbiome of plants pre-exposed to crude oil pollution could serve as a reservoir for mining group of bacterial with broad catabolic potentials for eco-recovery and waste treatment purposes.


Assuntos
Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Petróleo/análise , Alcanos/metabolismo , Bactérias/genética , Dioxigenases/genética , Dioxigenases/metabolismo , Genes Bacterianos , Complexos Multienzimáticos , Poluição por Petróleo/análise , Microbiologia do Solo
20.
Appl Environ Microbiol ; 87(14): e0000721, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33990303

RESUMO

4-Nitrophenol, a priority pollutant, is degraded by Gram-positive and Gram-negative bacteria via 1,2,4-benzenetriol (BT) and hydroquinone (HQ), respectively. All enzymes involved in the two pathways have been functionally identified. So far, all Gram-negative 4-nitrophenol utilizers are from the genera Pseudomonas and Burkholderia. But it remains a mystery why pnpG, an apparently superfluous BT 1,2-dioxygenase-encoding gene, always coexists in the catabolic cluster (pnpABCDEF) encoding 4-nitrophenol degradation via HQ. Here, the physiological role of pnpG in Burkholderia sp. strain SJ98 was investigated. Deletion and complementation experiments established that pnpG is essential for strain SJ98 growing on 4-nitrocatechol rather than 4-nitrophenol. During 4-nitrophenol degradation by strain SJ98 and its two variants (pnpG deletion and complementation strains), 1,4-benzoquinone and HQ were detected, but neither 4-nitrocatechol nor BT was observed. When the above-mentioned three strains (the wild type and complementation strains with 2,2'-dipyridyl) were incubated with 4-nitrocatechol, BT was the only intermediate detected. The results established the physiological role of pnpG that encodes BT degradation in vivo. Biotransformation analyses showed that the pnpA-deleted strain was unable to degrade both 4-nitrophenol and 4-nitrocatechol. Thus, the previously characterized 4-nitrophenol monooxygenase PnpASJ98 is also essential for the conversion of 4-nitrocatechol to BT. Among 775 available complete genomes for Pseudomonas and Burkholderia, as many as 89 genomes were found to contain the putative pnpBCDEFG genes. The paucity of pnpA (3 in 775 genomes) implies that the extension of BT and HQ pathways enabling the degradation of 4-nitrophenol and 4-nitrocatechol is rarer, more recent, and likely due to the release of xenobiotic nitroaromatic compounds. IMPORTANCE An apparently superfluous gene (pnpG) encoding BT 1,2-dioxygenase is always found in the catabolic clusters involved in 4-nitrophenol degradation via HQ by Gram-negative bacteria. Our experiments reveal that pnpG is not essential for 4-nitrophenol degradation in Burkholderia sp. strain SJ98 but instead enables its degradation of 4-nitrocatechol via BT. The presence of pnpG genes broadens the range of growth substrates to include 4-nitrocatechol or BT, intermediates from the microbial degradation of many aromatic compounds in natural ecosystems. In addition, the existence of pnpCDEFG in 11.6% of the above-mentioned two genera suggests that the ability to degrade BT and HQ simultaneously is ancient. The extension of BT and HQ pathways including 4-nitrophenol degradation seems to be an adaptive evolution for responding to synthetic nitroaromatic compounds entering the environment since the industrial revolution.


Assuntos
Proteínas de Bactérias/metabolismo , Burkholderia/enzimologia , Catecóis/metabolismo , Dioxigenases/metabolismo , Hidroquinonas/metabolismo , Nitrofenóis/metabolismo , Proteínas de Bactérias/genética , Biotransformação , Burkholderia/genética , Dioxigenases/genética , Pseudomonas/enzimologia , Pseudomonas/genética
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