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Brassinosteroid (BR) signaling and the C-class MADS-box gene AGAMOUS (AG) play important roles in ovule development in Arabidopsis (Arabidopsis thaliana). However, how BR signaling integrates with AG functions to control the female reproductive process remains elusive. Here, we showed that the regulatory role of BR signaling in proper ovule development is mediated by the transcriptional repressor gene ZINC FINGER PROTEIN 11 (ZFP11), which is a direct target of AG. ZFP11 expression initiates from the placenta upon AG induction and becomes prominent in the funiculus of ovule primordia. Plants harboring zfp11 mutations showed reduced placental length with decreased ovule numbers and some aborted ovules. During ovule development, the transcription factor BRASSINAZOLE-RESISTANT 1 (BZR1), which functions downstream of BR signaling, inhibits ZFP11 expression in the chalaza and nucellus. Weakened BR signaling leads to stunted integuments in ovules, resulting from the direct repression of INNER NO OUTER (INO) and WUSCHEL (WUS) by extended ZFP11 expression in the chalaza and nucellus, respectively. In addition, the zfp11 mutant shows reduced sensitivity to BR biosynthesis inhibitors and can rescue outer integument defects in brassinosteroid insensitive 1 (bri1) mutants. Thus, the precise spatial regulation of ZFP11, which is activated by AG in the placenta and suppressed by BR signaling in the central and distal regions of ovules, is essential for ensuring sufficient ovule numbers and proper ovule formation.
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The CK1 family are conserved serine/threonine kinases with numerous substrates and cellular functions. The fission yeast CK1 orthologues Hhp1 and Hhp2 were first characterized as regulators of DNA repair, but the mechanism(s) by which CK1 activity promotes DNA repair had not been investigated. Here, we found that deleting Hhp1 and Hhp2 or inhibiting CK1 catalytic activities in yeast or in human cells increased double-strand breaks (DSBs). The primary pathways to repair DSBs, homologous recombination and nonhomologous end joining, were both less efficient in cells lacking Hhp1 and Hhp2 activity. To understand how Hhp1 and Hhp2 promote DNA damage repair, we identified new substrates of these enzymes using quantitative phosphoproteomics. We confirmed that Arp8, a component of the INO80 chromatin remodeling complex, is a bona fide substrate of Hhp1 and Hhp2 important for DNA repair. Our data suggest that Hhp1 and Hhp2 facilitate DNA repair by phosphorylating multiple substrates, including Arp8.
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ETHNOPHARMACOLOGICAL RELEVANCE: Siwu tablet (SWT), derived from a traditional Chinese medicinal formula named Siwu decoction, is widely used for blood deficiency syndrome. Siwu decoction and its derived formulas have been proven to improve renal anemia and prevent senescence. Whether SWT prevents glomerular podocyte senescence and the underlying molecular mechanism remains unknow. AIM OF THE STUDY: To elucidate the protective effect and possible mechanism of SWT on glomerular podocyte senescence. MATERIAL AND METHODS: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed to characterize components of SWT. Male Sprague-Dawley rats were given 10% fructose drinking water for 16 weeks. SWT (810 and 1620 mg/kg) was administered orally for the last 8 weeks. The assays of senescence-associated beta-galactosidase (SA-ß-gal) staining, immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot as well as enzyme linked immunosorbent assay were performed to evaluate rat glomerular podocyte senescence. The mRNA and protein levels of nucleoporin 155 (Nup155) and inositol requiring mutant 80 (INO80) in rat glomeruli were detected by qRT-PCR, Western blot and immunofluorescence. Foot processes and nuclear pore complexes (NPCs) of rat glomerular podocytes were visualized by transmission electron microscopy. RESULTS: One hundred and fifty-nine components were preliminarily identified in SWT. The results of animal experiments showed that SWT decreased the activity of SA-ß-gal, protein levels of p16, p21, p53 and phosphorylated histone H2AX (γ-H2AX), and mRNA levels of interleukin-1ß (IL-1ß), IL-6 and tumor necrosis factor-α (TNF-α) in glomeruli of high fructose-fed rats. As expected, SWT increased renal cortex erythropoietin mRNA expression and serum erythropoietin concentration in this animal model. SWT reduced urine albumin-to-creatinine ratio and serum levels of uric acid, creatinine and blood urea nitrogen, and recovered glomerular structure injury in high fructose-fed rats. It up-regulated mRNA and protein levels of Nup155 and the number of podocyte NPCs, and subsequently reinforced mRNA nuclear export and protein expression of INO80 in rat glomeruli under high fructose stimulation. CONCLUSIONS: SWT ameliorates glomerular podocyte senescence in high fructose-fed rats possibly by increasing Nup155 to promote INO80 mRNA nuclear export.
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Background: Inhaled nitric oxide (iNO) can improve oxygenation in acute respiratory syndrome (ARDS), has anti-inflammatory and antithrombotic effects, and can inhibit coronavirus- replication. The study aim was to investigate the impact of iNO in COVID-19 associated ARDS (CARDS) on oxygenation, the length of mechanical ventilation (MV), the level of inflammatory markers and the rate of thrombotic events during ICU stay. Methods: This was a retrospective, observational, monocentric study analyzing the effect of INO (15 parts per million) vs. non-iNO in adult ventilated CARDS patients on oxygenation, the level of inflammatory markers, and the rate of thrombotic events during ICU stay. Within the iNO group, the impact on gas exchange was assessed by comparing arterial blood gas results obtained at different time points. Results: Overall, 19/56 patients were treated with iNO, with no difference regarding sex, age, body mass index, and SOFA-/APACHE II- score between the iNO and non-iNO groups. iNO improved oxygenation in iNO-responders (7/19) and had no impact on inflammatory markers or the rate of thrombotic events but was associated with an increased MV length. Conclusions: iNO was able to improve oxygenation in CARDS in iNO-responders but did not show an impact on inflammatory markers or the rate of thrombotic events, while it was associated with an increased MV length.
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Testicular development and spermatogenesis in mice involve complex and dynamic gene regulation and chromatin remodelling. In this study, Real-time fluorescence quantitative PCR (RT-qPCR), Western Blot (WB), Immunofluorescence (IF), transfection and other techniques were used to analyse the expression of Ino80d mRNA and its encoded proteins in mouse testicular tissue and mouse spermatogonial cells, and to further analyse the possible target-regulatory relationship and function of miR-92a-3p and Ino80d. We found that Ino80d mRNA and protein expression was up-regulated in adult mouse testis tissue relative to juvenile mouse testis tissue, whereas miR-92a-3p expression was down-regulated in adult mouse testis tissue. Immunofluorescence results showed that the Ino80d protein was mainly localized in the nucleus of male germ cells. Ino80d protein expression is higher in spermatogonia, spermatid and lower in primary spermatocytes, secondary spermatocytes and sperm. There is a decreasing trend in development from spermatogonia to secondary spermatocytes. The transfection results showed that the expression levels of Ino80d mRNA and protein were down-regulated after overexpression of miR-92a-3p in mouse spermatogonia. Increased miR-92a-3p may be a key factor in inhibiting the expression of Ino80d mRNA and proteins in the miR-92a-3p mimics group of mouse spermatogonial cells, whereas differential expression may be a result of the negative regulation of miR-92a-3p, which regulates testicular development and spermatogenesis in mice.
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The yeast Saccharomyces cerevisiae Opi1p negatively regulates phospholipid biosynthetic genes. Under derepressing conditions, Opi1p binds to the endoplasmic reticulum/nuclear membrane with the aid of the membrane protein Scs2p and phosphatidic acids under derepressing conditions. Under repressing conditions, it enters the nucleus to inhibit the positive transcription factors Ino2p and Ino4p. While the spatial regulation of Opi1p is understood, the regulation of its abundance remains unclear. We investigated the role of Scs2p and Ino2p in Opi1p stability by overexpressing these proteins in yeast cells. Opi1p was stable in the presence of Scs2p, but mutations in residues required for interaction with Scs2p caused Opi1p unstable. Even in the absence of Scs2p, Opi1p remained stable in the strain having a mutation to increase phosphatidic acid levels. Conversely, overproduction of Ino2p reduced Opi1p stability, whereas a mutant Ino2p that cannot interact with Opi1p did not. Additionally, Opi1p was stable in strains lacking Ino2p or with a mutated Ino2p-binding domain. These findings suggest that regulation, adding another layer to the regulation of phospholipid biosynthetic gene expression by Opi1p.
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Chromatin remodelling complexes (CRC) are ATP-dependent molecular machines important for the dynamic organization of nucleosomes along eukaryotic DNA. CRCs SWI/SNF, RSC and INO80 can move positioned nucleosomes in promoter DNA, leading to nucleosome-depleted regions which facilitate access of general transcription factors. This function is strongly supported by transcriptional activators being able to interact with subunits of various CRCs. In this work we show that SWI/SNF subunits Swi1, Swi2, Snf5 and Snf6 can bind to activation domains of Ino2 required for expression of phospholipid biosynthetic genes in yeast. We identify an activator binding domain (ABD) of ATPase Swi2 and show that this ABD is functionally dispensable, presumably because ABDs of other SWI/SNF subunits can compensate for the loss. In contrast, mutational characterization of the ABD of the Swi2-related ATPase Sth1 revealed that some conserved basic and hydrophobic amino acids within this domain are essential for the function of Sth1. While ABDs of Swi2 and Sth1 define separate functional protein domains, mapping of an ABD within ATPase Ino80 showed co-localization with its HSA domain also required for binding actin-related proteins. Comparative interaction studies finally demonstrated that several unrelated activators each exhibit a specific binding pattern with ABDs of Swi2, Sth1 and Ino80.
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Adenosina Trifosfatases , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA , Ligação Proteica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Fatores de Transcrição , Ativação Transcricional , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Montagem e Desmontagem da Cromatina/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Regulação Fúngica da Expressão Gênica , Domínios Proteicos , Proteínas Nucleares , Proteínas de Ciclo Celular , Fatores de Transcrição Hélice-Alça-Hélice BásicosRESUMO
Improving the thermal and dielectric properties of insulation oil (INO) with nanoadditives is an important challenge, and achieving dispersion stability in these nanofluids is quite challenging, necessitating further investigation. The main goal of this study is the synthesis and use of the hydrophobicity of zinc ferrite (ZnFe2O4) nanoparticles, which can improve both the thermal and dielectric properties of the INO. This oil is made from distillate (petroleum), including severely hydrotreated light naphthenic oil (75-85%) and severely hydrotreated light paraffinic oil (15-25%). A comprehensive investigation was carried out, involving the creation of nanofluids with ZnFe2O4 nanoparticles at various concentrations, and employing various characterization methods such as X-ray diffraction (XRD), Fourier-transform infrared (FTIR), scanning electron microscopy, energy dispersive X-ray (EDX), zeta potential analysis, and dynamic light scattering (DLS). The KD2 Pro thermal analyzer was used to investigate the thermal characteristics, including the thermal conductivity coefficient (TCC) and volumetric heat capacity (VHC). Under free convection conditions, the free convection heat transfer coefficient (FCHTC) and Nusselt numbers (Nu) were evaluated, revealing enhancements ranging from 14.15 to 11.7%. Furthermore, the most significant improvement observed in the AC Breakdown voltage (BDV) for nanofluids containing 0.1 wt% of ZnFe2O4 amounted to 17.3%. The most significant finding of this study is the improvement in the heat transfer performance, AC BDV, and stability of the nanofluids.
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Background: Patients with multiple comorbidities can present as a diagnostic challenge as overlapping symptomatology complicates the discovery of emergent pathology. Symptoms of alcohol misuse or orthostatic hypotension may especially cloud the diagnosis of insidious neurological disease, such as posterior circulation infarct. With a growing elderly population, it is expected that the complex multimorbid patient will represent a growing challenge to prompt stroke detection and treatment. Case Description: Herein, we present a 69-year-old male with a history of alcohol abuse, chronic obstructive pulmonary disease, type 2 diabetes mellitus, paroxysmal atrial fibrillation, and congestive heart disease. The patient arrived at our emergency department with dizziness, ataxia, and diplopia. His symptoms had a sudden onset and gradual exacerbation over a span of 2 days, notably aggravated by standing and walking, but relieved when seated or supine. Notably, a month before admission, the patient had been treated with anti-congestive medications for severe congestive heart failure leading to a weight loss of 55 lbs over period of 2 weeks. The initial differential diagnoses were orthostatism, Wernicke's encephalopathy (WE), and ischemic stroke. Magnetic resonance imaging (MRI) revealed a subacute infarct in the medial longitudinal fasciculus (MLF). Conclusions: The case underscores the challenge in diagnosing neurological conditions in multimorbid individuals. The combination of various underlying conditions may drastically complicate the diagnosis. Successful diagnosis and treatment necessitates meticulous evaluation of clinical observations, medical history, current medications, and pertinent diagnostic evaluations to effectively narrow down the potential differential diagnoses.
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The INO80D protein, a component of the INO80 chromatin remodeling complex, plays a pivotal role in chromatin remodeling, gene expression, and DNA repair within mammalian sperm. In contrast to the condensed nuclear structure of mammalian sperm, Chinese mitten crab, Eriocheir sinensis, exhibits a distinctively decondensed sperm nucleus. The distribution and function of INO80D during the E. sinensis spermatogenesis were previously enigmatic. Our research endeavored to elucidate the distribution and function of INO80D, thereby enhancing our comprehension of sperm decondensation and the process of spermatogenesis in this species. Employing transcriptome sequencing, RT-qPCR, western blot analysis, and immunofluorescence techniques, we observed a pronounced upregulation of INO80D in the adult E. sinensis in comparison to the juvenile. The protein predominantly resides in the cellular nucleus, with high levels in spermatogonia and spermatocytes, less in stage I and III spermatids, and lowest in mature sperm. The results indicated that INO80D is initially instrumental in chromatin decondensation to facilitate gene accessibility and DNA repair during the early phases of spermatogenesis. Its role subsequently shifts to maintaining decondensed chromatin stability and genetic integrity during spermiogenesis. The sustained presence of INO80D during spermiogenesis is essential for the ultimate maturation of the decondensed sperm nucleus, imperative for preserving the unique decondensed state and the protection of genetic material in E. sinensis. Our study concludes that INO80D exerts a multifaceted influence on the spermatogenesis of E. sinensis, impacting chromatin decondensation, genetic integrity, and the regulation of early gene expression. This understanding could potentially improve crab breeding in aquaculture.
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Braquiúros , Montagem e Desmontagem da Cromatina , Espermatogênese , Animais , Espermatogênese/genética , Masculino , Braquiúros/genética , Espermatozoides/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/genética , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismoRESUMO
Building a polarization center is an effective avenue to boost charge separation and molecular activation in photocatalysis. However, a limited number of polarization centers are usually created. Here, a polarization plane based on two-dimensional (2D) atomic layers is designed to maximize the surface polarization centers. The Mn in a 2D crystal lattice is etched from the MnIn2S4 atomic layers to build a consecutive symmetry-breaking structure of isolated InO1S5 sites. More charges aggregate around O, making the isolated InO1S5 sites highly polarized. Due to the formation of the InO1S5 polarization plane, an enormous polarized electric field is formed perpendicular to the 2D atomic layers and the carrier lifetime can be prolonged from 93.2 ps in MnIn2S4 to 1130 ps in amorphous MnxIn2Sy. Meantime, the formed large charge density gradient favors coupling and activation of small molecules. Benefiting from these features, a good NH3 photosynthesis performance (515.8 µmol g-1 h-1) can be realized over amorphous MnxIn2Sy, roughly 2.5 and 48.9 times higher than those of MnIn2S4 atomic layers and bulk MnIn2S4, respectively. The apparent quantum yields reach 5.4 and 3.3% at 380 and 400 nm, respectively. Meanwhile, a greatly improved CO2 reduction activity is also achieved over MnxIn2Sy. This strategy provides an accessible pathway for designing an asymmetrical polarization plane to motivate photocatalysis optimization.
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INTRODUCTION: Podocyte senescence causes podocyte loss and glomerulopathy. Excessive fructose intake is a risk factor for podocyte injury. However, whether high fructose promotes podocyte senescence remains unknown. OBJECTIVES: To explore the pathological mechanism by which high fructose drives podocyte senescence and find natural compounds to alleviate podocyte senescence. METHODS: Podocyte senescence was characterized with senescence-associated beta-galactosidase (SA-ß-gal) staining, Western blot, real-time quantitative polymerase chain reaction (qRT-PCR), comet assay and immunofluorescence. Proteomics analysis was performed to identify differentially expressed proteins in high fructose-exposed podocytes. Podocyte nuclear pore complexes (NPCs) and foot processes were observed by transmission electron microscopy. The mRNA and protein levels of nucleoporin 155 (Nup155) and inositol requiring mutant 80 (INO80) were detected by qRT-PCR, Western blot and immunofluorescence. Virtual screening was conducted to find natural compounds that target Nup155. RESULTS: High fructose increased SA-ß-gal activity, protein level of p53, p21, p16 and phosphorylated histone H2AX (γ-H2AX), as well as mRNA expression of interleukin-1ß (IL-1ß), IL-6 and tumor necrosis factor α (TNF-α) in rat glomeruli and podocytes. Proteomic analysis unraveled a crucial molecule Nup155, which was decreased in high fructose-induced podocyte senescence. Meanwhile, the number of podocyte NPCs was also decreased in vivo and in vitro. Consistently, high fructose suppressed nuclear export of INO80 mRNA, thereby down-regulated INO80 protein expression in podocyte senescence. Deletion of Nup155 inhibited INO80 mRNA nuclear export to induce podocyte senescence, whereas overexpression of Nup155 or INO80 alleviated high fructose-induced podocyte senescence. Ferulic acid was found to up-regulate Nup155 by both direct binding to stabilize Nup155 protein and enhancing its transcription, to promote INO80 mRNA nuclear export in the mitigation of high fructose-caused podocyte senescence. CONCLUSION: High fructose induces podocyte senescence by decreasing Nup155 to inhibit INO80 mRNA nuclear export. Ferulic acid targeting Nup155 may be a potential strategy to prevent high fructose-induced podocyte senescence.
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BACKGROUND: Nitric oxide (NO) is a strong vasodilator, selectively directed on pulmonary circulation through inhaled administration. In adult intensive care units (ICU), it is mainly used for refractory hypoxemia in mechanically ventilated patients. Several medical delivery devices have been developed to deliver inhaled nitric oxide (iNO). The main purpose of those devices is to guarantee an accurate inspiratory NO concentration, whatever the ventilator used, with NO2 concentrations lower than 0.3 ppm. We hypothesized that the performances of the different available iNO delivery systems could depend on their working principle and could be influenced by the ventilator settings. The objective of this study was to assess the accuracy of seven different iNO-devices combined with different ICU ventilators' flow-by to reach inspiratory NO concentration targets and to evaluate their potential risk of toxicity. METHODS: We tested seven iNO-devices on a test-lung connected to distinct ICU ventilators offering four different levels of flow-by. We measured the flow in the inspiratory limb of the patient circuit and the airway pressure. The nitric oxide/nitrogen (NO/N2) flow was measured on the administration line of the iNO-devices. NO and NO2 concentrations were measured in the test-lung using an electrochemical analyzer. RESULTS: We identified three iNO-device generations based on the way they deliver NO flow: "Continuous", "Sequential to inspiratory phase" (I-Sequential) and "Proportional to inspiratory and expiratory ventilator flow" (Proportional). Median accuracy of iNO concentration measured in the test lung was 2% (interquartile range, IQR -19; 36), -23% (IQR -29; -17) and 0% (IQR -2; 0) with Continuous, I-Sequential and Proportional devices, respectively. Increased ventilator flow-by resulted in decreased iNO concentration in the test-lung with Continuous and I-Sequential devices, but not with Proportional ones. NO2 formation measured to assess potential risks of toxicity never exceeded the predefined safety target of 0.5 ppm. However, NO2 concentrations higher than or equal to 0.3 ppm, a concentration that can cause bronchoconstriction, were observed in 19% of the different configurations. CONCLUSION: We identified three different generations of iNO-devices, based on their gas administration modalities, that were associated with highly variable iNO concentrations' accuracy. Ventilator's flow by significantly impacted iNO concentration. Only the Proportional devices permitted to accurately deliver iNO whatever the conditions and the ventilators tested.
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Epigenetics is the study of heritable changes to the genome and gene expression patterns that are not caused by direct changes to the DNA sequence. Examples of these changes include posttranslational modifications to DNA-bound histone proteins, DNA methylation, and remodeling of nuclear architecture. Collectively, epigenetic changes provide a layer of regulation that affects transcriptional activity of genes while leaving DNA sequences unaltered. Sequence variants or mutations affecting enzymes responsible for modifying or sensing epigenetic marks have been identified in patients with congenital heart disease (CHD), and small-molecule inhibitors of epigenetic complexes have shown promise as therapies for adult heart diseases. Additionally, transgenic mice harboring mutations or deletions of genes encoding epigenetic enzymes recapitulate aspects of human cardiac disease. Taken together, these findings suggest that the evolving field of epigenetics will inform our understanding of congenital and adult cardiac disease and offer new therapeutic opportunities.
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Metilação de DNA , Epigênese Genética , Humanos , Animais , Metilação de DNA/genética , Cardiopatias Congênitas/genética , Histonas/metabolismo , Histonas/genética , Processamento de Proteína Pós-Traducional , Camundongos , Cardiopatias/genética , Cardiopatias/metabolismo , MutaçãoRESUMO
The INO80 chromatin remodeler is a versatile enzyme capable of several functions, including spacing nucleosomes equal distances apart, precise positioning of nucleosomes based on DNA shape/sequence and exchanging histone dimers. Within INO80, the Arp5 subunit plays a central role in INO80 remodeling, evidenced by its interactions with the histone octamer, nucleosomal and extranucleosomal DNA, and its necessity in linking INO80's ATPase activity to nucleosome movement. Our investigation reveals that the grappler domain of Arp5 interacts with the acidic pocket of nucleosomes through two distinct mechanisms: an arginine anchor or a hydrophobic/acidic patch. These two modes of binding serve distinct functions within INO80 as shown in vivo by mutations in these regions resulting in varying phenotypes and in vitro by diverse effects on nucleosome mobilization. Our findings suggest that the hydrophobic/acidic patch of Arp5 is likely important for dimer exchange by INO80, while the arginine anchor is crucial for mobilizing nucleosomes.
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Pivotal trials investigating the use of inhaled nitric oxide (iNO) in the 1990s led to approval by the Food and Drug Administration in 1999. Inhaled nitric oxide is the only approved pulmonary vasodilator for persistent pulmonary hypertension of the newborn (PPHN). Selective pulmonary vasodilation with iNO in near-term and term neonates with PPHN is safe, and targeted use of iNO in less mature neonates with pulmonary hypertension (PH) can be beneficial. This review addresses a brief history of iNO, clinical features of neonatal PH, and the clinical application of iNO.
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Hipertensão Pulmonar , Síndrome da Persistência do Padrão de Circulação Fetal , Recém-Nascido , Humanos , Óxido Nítrico/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Administração por Inalação , Síndrome da Persistência do Padrão de Circulação Fetal/tratamento farmacológico , PulmãoRESUMO
The transcription factor complex INO2 and INO4 in Saccharomyces cerevisiae plays a vital role in lipid biosynthesis by activating multiple genes in the biosynthetic pathways of phospholipid, fatty acid, and sterol. Previous studies have reported conflicting results regarding the effects of ino2 and ino4 gene expression levels on target chemicals. Therefore, this study aimed to examine the influence of different ino2 and ino4 expression levels on carotenoid production (e.g., lycopene), which shares a common precursor, acetyl-CoA, with lipid metabolism. Surprisingly, 2.6- and 1.8-fold increase in lycopene yield in the ino2 and ino4 deletion strains were found, respectively. In contrast, ino2 overexpression did not promote lycopene accumulation. Additionally, there was a decrease in intracellular free fatty acids in the ino2 deletion strain. Comparative transcriptome analysis revealed a significant downregulation of genes related to lipid biosynthesis in the ino2 deletion strain. To our knowledge, this is the first report showing that deletion of transcription factor genes ino2 and ino4 can facilitate lycopene accumulation. These findings hold significant implications for the development of metabolically engineered S. cerevisiae with enhanced carotenoid production.
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Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Repressoras/genética , Metabolismo dos Lipídeos/genética , Licopeno , Fosfolipídeos/metabolismo , Regulação Fúngica da Expressão GênicaRESUMO
Chromatin remodelers are important in maintaining the dynamic chromatin state in eukaryotic cells, which is essential for epigenetic regulation. Among the remodelers, the multi-subunits complex INO80 plays crucial roles in transcriptional regulation. However, current knowledge of chromatin regulation of the core subunit Ino80 on stress adaptation remains mysterious. Here we revealed that overexpressing the chromatin remodeler Ino80 elevated tolerance to multiple stresses in budding yeast Saccharomyces cerevisiae. Analyses of differential chromatin accessibility and global transcription levels revealed an enrichment of genes involved in NCR (nitrogen catabolite repression) under acetic acid stress. We demonstrated that Ino80 overexpression reduced the histone H3 occupancy in the promoter region of the glutamate dehydrogenase gene GDH2 and the allantoinase gene DAL1. Consistently, the decreased occupancy of nucleosome was revealed in the Ino80-inactivation mutant. Further analyses showed that Ino80 was recruited to the specific DNA locus in the promoter region of GDH2. Consistently, Ino80 overexpression facilitated the utilization of non-preferred nitrogen source to enhance ethanol yield under prolonged acetic acid stress. These results demonstrate that Ino80 plays a crucial role in coordinating carbon and nitrogen metabolism during stress adaptation.
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Repressão Catabólica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Cromatina/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Epigênese Genética , Nucleossomos , Acetatos/metabolismoRESUMO
The aberrant function of ATP-dependent chromatin remodeler INO80 has been implicated in multiple types of cancers by altering chromatin architecture and gene expression; however, the underlying mechanism of the functional involvement of INO80 mutation in cancer etiology, especially in breast cancer, remains unclear. In the present study, we have performed a weighted gene co-expression network analysis (WCGNA) to investigate links between INO80 expression and breast cancer sub-classification and progression. Our analysis revealed that INO80 repression is associated with differential responsiveness of estrogen receptors (ERs) depending upon breast cancer subtype, ER networks, and increased risk of breast carcinogenesis. To determine whether INO80 loss induces breast tumors, a conditional INO80-knockout (INO80 cKO) mouse model was generated using the Cre-loxP system. Phenotypic characterization revealed that INO80 cKO led to reduced branching and length of the mammary ducts at all stages. However, the INO80 cKO mouse model had unaltered lumen morphology and failed to spontaneously induce tumorigenesis in mammary gland tissue. Therefore, our study suggests that the aberrant function of INO80 is potentially associated with breast cancer by modulating gene expression. INO80 mutation alone is insufficient for breast tumorigenesis.
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Internuclear ophthalmoplegia (INO) is a condition characterized by impaired ocular movement, leading to an inability to perform coordinated lateral gaze, resulting in ophthalmoplegia. This impairment results from damage to the medial longitudinal fasciculus (MLF), which can occur because of various types of lesions localized in the pons or midbrain. In this case, we report on a 67-year-old man with multiple comorbidities who arrived at the emergency department with complaints of sudden dizziness and an unsteady gait. During the examination, he exhibited left INO, which was characterized by limited left eye adduction and multidirectional nystagmus of the right eye when performing right lateral gaze.