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1.
Mol Med Rep ; 29(4)2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38391118

RESUMO

Prothymosin α (ProT), a highly acidic nuclear protein with multiple cellular functions, has shown potential neuroprotective properties attributed to its anti­necrotic and anti­apoptotic activities. The present study aimed to investigate the beneficial effect of ProT on neuroplasticity after ischemia­reperfusion injury and elucidate its underlying mechanism of action. Primary cortical neurons were either treated with ProT or overexpressing ProT by gene transfection and exposed to oxygen­glucose deprivation for 2 h in vitro. Immunofluorescence staining for ProT and MAP­2 was performed to quantify ProT protein expression and assess neuronal arborization. Mice treated with vehicle or ProT (100 µg/kg) and ProT overexpression in transgenic mice received middle cerebral artery occlusion for 50 min to evaluate the effect of ProT on neuroplasticity­associated protein following ischemia­reperfusion injury. The results demonstrated that in cultured neurons ProT significantly increased neurite lengths and the number of branches, accompanied by an upregulation mRNA level of brain­derived neurotrophic factor. Furthermore, ProT administration improved the protein expressions of synaptosomal­associated protein, 25 kDa and postsynaptic density protein 95 after ischemic­reperfusion injury in vivo. These findings suggested that ProT can potentially induce neuroplasticity effects following ischemia­reperfusion injury.


Assuntos
Traumatismo por Reperfusão , Timosina , Timosina/análogos & derivados , Camundongos , Animais , Camundongos Transgênicos , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Regulação para Cima , Timosina/genética , Timosina/farmacologia , Timosina/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico
2.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834178

RESUMO

The intestinal barrier comprises a single layer of epithelial cells tightly joined to form a physical barrier. Disruption or compromise of the intestinal barrier can lead to the inadvertent activation of immune cells, potentially causing an increased risk of chronic inflammation in various tissues. Recent research has suggested that specific dietary components may influence the function of the intestinal barrier, potentially offering a means to prevent or mitigate inflammatory disorders. However, the precise mechanism underlying these effects remains unclear. Bovine colostrum (BC), the first milk from cows after calving, is a natural source of nutrients with immunomodulatory, anti-inflammatory, and gut-barrier fortifying properties. This novel study sought to investigate the transcriptome in BC-treated Zonulin transgenic mice (Ztm), characterized by dysbiotic microbiota, intestinal hyperpermeability, and mild hyperactivity, applying RNA sequencing. Seventy-five tissue samples from the duodenum, colon, and brain of Ztm and wild-type (WT) mice were dissected, processed, and RNA sequenced. The expression profiles were analyzed and integrated to identify differentially expressed genes (DEGs) and differentially expressed transcripts (DETs). These were then further examined using bioinformatics tools. RNA-seq analysis identified 1298 DEGs and 20,952 DETs in the paired (Ztm treatment vs. Ztm control) and reference (WT controls) groups. Of these, 733 DEGs and 10,476 DETs were upregulated, while 565 DEGs and 6097 DETs were downregulated. BC-treated Ztm female mice showed significant upregulation of cingulin (Cgn) and claudin 12 (Cldn12) duodenum and protein interactions, as well as molecular pathways and interactions pertaining to tight junctions, while BC-treated Ztm males displayed an upregulation of transcripts like occludin (Ocln) and Rho/Rac guanine nucleotide exchange factor 2 (Arhgf2) and cellular structures and interfaces, protein-protein interactions, and organization and response mechanisms. This comprehensive analysis reveals the influence of BC treatment on tight junctions (TJs) and Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signaling pathway gene expressions. The present study is the first to analyze intestinal and brain samples from BC-treated Ztm mice applying high-throughput RNA sequencing. This study revealed molecular interaction in intestinal barrier function and identified hub genes and their functional pathways and biological processes in response to BC treatment in Ztm mice. Further research is needed to validate these findings and explore their implications for dietary interventions aimed at improving intestinal barrier integrity and function. The MGH Institutional Animal Care and Use Committee authorized the animal study (2013N000013).


Assuntos
Colostro , Haptoglobinas , Mucosa Intestinal , Precursores de Proteínas , Transcriptoma , Animais , Bovinos , Feminino , Masculino , Camundongos , Gravidez , Mucosa Intestinal/metabolismo , Camundongos Transgênicos , Junções Íntimas/metabolismo , Haptoglobinas/genética , Precursores de Proteínas/genética
3.
Elife ; 112022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205393

RESUMO

At CA1→subiculum synapses, alternatively spliced neurexin-1 (Nrxn1SS4+) and neurexin-3 (Nrxn3SS4+) enhance NMDA-receptors and suppress AMPA-receptors, respectively, without affecting synapse formation. Nrxn1SS4+ and Nrxn3SS4+ act by binding to secreted cerebellin-2 (Cbln2) that in turn activates postsynaptic GluD1 receptors. Whether neurexin-Cbln2-GluD1 signaling has additional functions besides regulating NMDA- and AMPA-receptors, and whether such signaling performs similar roles at other synapses, however, remains unknown. Here, we demonstrate using constitutive Cbln2 deletions in mice that at CA1→subiculum synapses, Cbln2 performs no additional developmental roles besides regulating AMPA- and NMDA-receptors. Moreover, low-level expression of functionally redundant Cbln1 did not compensate for a possible synapse-formation function of Cbln2 at CA1→subiculum synapses. In exploring the generality of these findings, we examined the prefrontal cortex where Cbln2 was recently implicated in spinogenesis, and the cerebellum where Cbln1 is known to regulate parallel-fiber synapses. In the prefrontal cortex, Nrxn1SS4+-Cbln2 signaling selectively controlled NMDA-receptors without affecting spine or synapse numbers, whereas Nrxn3SS4+-Cbln2 signaling had no apparent role. In the cerebellum, conversely, Nrxn3SS4+-Cbln1 signaling regulated AMPA-receptors, whereas now Nrxn1SS4+-Cbln1 signaling had no manifest effect. Thus, Nrxn1SS4+- and Nrxn3SS4+-Cbln1/2 signaling complexes differentially control NMDA- and AMPA-receptors in different synapses in diverse neural circuits without regulating synapse or spine formation.


Assuntos
Proteínas de Ligação ao Cálcio , Moléculas de Adesão de Célula Nervosa , Receptores de AMPA , Receptores de N-Metil-D-Aspartato , Animais , Camundongos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo , N-Metilaspartato/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/fisiologia , Proteínas de Ligação ao Cálcio/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo
4.
World J Gastroenterol ; 28(29): 3917-3933, 2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-36157551

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Current guidelines for HCC management recommend surveillance of high-risk patients every 6 mo using ultrasonography. Serum biomarkers, like alpha-fetoprotein (AFP), protein induced by vitamin K absence/antagonist-II (PIVKA-II) and lectin-reactive AFP, show suboptimal performance for detection of HCC, which is crucial for successful resection or treatment. Thus, there is a significant need for new biomarkers to aid early diagnosis of HCC. Studies have shown that the expression level of human microRNAs (miRNAs), a small, non-coding RNA species released into the blood, can serve as an early marker for various diseases, including HCC. AIM: To evaluate the diagnostic role of miRNAs in HCC as single markers, signatures or in combination with known protein biomarkers. METHODS: Our prospective, multicenter, case-control study recruited 660 participants (354 controls with chronic liver disease and 306 participants with HCC) and employed a strategy of initial screening by two independent methods, real-time quantitative PCR (n = 60) and next-generation sequencing (n = 100), to assess a large number of miRNAs. The results from the next-generation sequencing and real-time quantitative PCR screening approaches were then combined to select 26 miRNAs (including two putative novel miRNAs). Those miRNAs were analyzed for their diagnostic potential as single markers or in combination with other miRNAs or established protein biomarkers AFP and PIVKA-II via real-time quantitative PCR in training (n = 200) and validation cohorts (n = 300). RESULTS: We identified 26 miRNAs that differentiated chronic liver disease controls from (early) HCC via two independent discovery approaches. Three miRNAs, miR-21-5p (miR-21), miR-320a and miR-186-5p, were selected by both methods. In the training cohort, only miR-21, miR-320d and miR-423 could significantly distinguish (Q < 0.05) between the HCC and chronic liver disease control groups. In the multivariate setting, miR-21 with PIVKA-II was selected as the best combination, resulting in an area under the curve of 0.87 for diagnosis and area under the curve of 0.74 for early diagnosis of HCC. In the validation cohort, only miR-21 and miR-423 could be confirmed as potential HCC biomarkers. A combination of miRNAs did not perform better than any single miRNA. Improvement of PIVKA-II performance through combination with miRNAs could not be confirmed in the validation panel. Two putative miRs, put-miR-6 and put-miR-99, were tested in the training and validation panels, but their expression could only be detected in very few samples and at a low level (cycle threshold between 31.24 and 34.97). CONCLUSION: miRNAs alone or as a signature in combination with protein biomarkers AFP and PIVKA-II do not improve the diagnostic performance of the protein biomarkers.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Biomarcadores , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Detecção Precoce de Câncer , Humanos , Lectinas , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Estudos Prospectivos , Precursores de Proteínas/genética , Protrombina/genética , Vitamina K , alfa-Fetoproteínas/análise
5.
Biochimie ; 201: 33-42, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35792308

RESUMO

Various approaches have been explored to study skin biology, including the use of stem cells. Mesenchymal stem cells (MSCs) from the umbilical cord can be safely and easily obtained; however, a simple strategy to monitor their differentiation is essential. Involucrin is a marker of keratinocyte differentiation, and its promoter (pINV) directs stratum-specific expression of this protein. We designed a reporter system containing EGFP under the control of pINV to assess MSC transdifferentiation into keratinocytes. The functional sequence of pINV was inserted into a lentiviral vector, producing LeGO-GpINV. MSCs were transduced with LeGO-GpINV and induced to transdifferentiate into keratinocytes under cultivation with keratinocyte serum-free medium. MSC transdifferentiation was confirmed by morphological changes and by the expression of epidermal markers by flow cytometry, quantitative PCR, Western blot and the activity of epidermal kallikreins 5, 6 and 7. After 14 days of transdifferentiation, MSCs transduced with LeGO-GpINV showed an increase in EGFP fluorescence and expressed CK10, CK14, involucrin and filaggrin. There was also an increase in kallikrein activity. This reporter system allowed us to temporally assess epidermal differentiation, simultaneously with involucrin expression, opening possibilities for the in vivo study of skin biology and in regenerative medicine.


Assuntos
Queratinócitos , Precursores de Proteínas , Diferenciação Celular/genética , Células Cultivadas , Calicreínas/metabolismo , Queratinócitos/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo
6.
Cell Rep ; 40(2): 111061, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35830793

RESUMO

Although frameshift mutations lead to 22% of inherited Mendelian disorders in humans, there is no efficient in vivo gene therapy strategy available to date, particularly in nondividing cells. Here, we show that nonhomologous end-joining (NHEJ)-mediated nonrandom editing profiles compensate the frameshift mutation in the Pcdh15 gene and restore the lost mechanotransduction function in postmitotic hair cells of Pcdh15av-3J mice, an animal model of human nonsyndromic deafness DFNB23. Identified by an ex vivo evaluation system in cultured cochlear explants, the selected guide RNA restores reading frame in approximately 50% of indel products and recovers mechanotransduction in more than 70% of targeted hair cells. In vivo treatment shows that half of the animals gain improvements in auditory responses, and balance function is restored in the majority of injected mutant mice. These results demonstrate that NHEJ-mediated reading-frame restoration is a simple and efficient strategy in postmitotic systems.


Assuntos
Proteínas Relacionadas a Caderinas , Perda Auditiva Neurossensorial , Precursores de Proteínas , Animais , Sistemas CRISPR-Cas , Proteínas Relacionadas a Caderinas/genética , Modelos Animais de Doenças , Edição de Genes , Perda Auditiva Neurossensorial/genética , Perda Auditiva Neurossensorial/patologia , Humanos , Mecanotransdução Celular , Camundongos , Precursores de Proteínas/genética
7.
Int J Mol Sci ; 23(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35743044

RESUMO

The human genetic variant BDNF (V66M) represents the first example of neurotrophin family member that has been linked to psychiatric disorders. In order to elucidate structural differences that account for the effects in cognitive function, this hproBDNF polymorph was expressed, refolded, purified, and compared directly to the WT variant for the first time for differences in their 3D structures by DSF, limited proteolysis, FT-IR, and SAXS measurements in solution. Our complementary studies revealed a deep impact of V66M polymorphism on hproBDNF conformations in solution. Although the mean conformation in solution appears to be more compact in the V66M variant, overall, we demonstrated a large increase in flexibility in solution upon V66M mutation. Thus, considering that plasticity in IDR is crucial for protein function, the observed alterations may be related to the functional alterations in hproBDNF binding to its receptors p75NTR, sortilin, HAP1, and SorCS2. These effects can provoke altered intracellular neuronal trafficking and/or affect proBDNF physiological functions, leading to many brain-associated diseases and conditions such as cognitive impairment and anxiety. The structural alterations highlighted in the present study may pave the way to the development of drug discovery strategies to provide greater therapeutic responses and of novel pharmacologic strategy in human populations with this common polymorphism, ultimately guiding personalized medicine for neuropsychiatric disorders.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Transtornos Mentais , Precursores de Proteínas , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Humanos , Transtornos Mentais/genética , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Espalhamento a Baixo Ângulo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(2): 285-290, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35332731

RESUMO

Objective: To explore the internal mechanism of hepatocellular carcinoma (HCC) induced by chronic hepatitis B virus (HBV) infection. Methods: L02, HepG2 and Huh7 cells stably overexpressing HBV preS1 antigen were analyzed by flow cytometry, qRT-PCR and tumorigenesis in nude mice to evaluate the effect of preS1 antigen in HBV-related hepatocarcinogenesis. Results: Our results showed that the expression of cancer stem cell (CSCs) related factors and cell surface markers in preS1 overexpressing cells were up-regulated, and the tumorigenicity of these cells was enhanced in nude mice. In addition, preS1 overexpression could down-regulate the expression of major histocompatibility complex Ⅰ (MHC-Ⅰ). The expression of MHC-Ⅰ on the cell surface could be restored by adding interferon gamma (IFN-γ) in the process of cell culturing and the tumorigenicity of cells in nude mice could thus be reduced. Conclusion: Based on the above results, we believe that preS1 is a carcinogen of HBV and that it promotes the formation of liver cancer through down regulating MHC-Ⅰ on the surface of hepatocytes.


Assuntos
Carcinoma Hepatocelular , Genes MHC Classe I , Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Neoplasias Hepáticas , Precursores de Proteínas , Animais , Carcinogênese , Carcinoma Hepatocelular/virologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatócitos/virologia , Neoplasias Hepáticas/virologia , Camundongos , Camundongos Nus , Precursores de Proteínas/genética
9.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35121658

RESUMO

Pathogenic variants in surfactant proteins SP-B and SP-C cause surfactant deficiency and interstitial lung disease. Surfactant proteins are synthesized as precursors (proSP-B, proSP-C), trafficked, and processed via a vesicular-regulated secretion pathway; however, control of vesicular trafficking events is not fully understood. Through the Undiagnosed Diseases Network, we evaluated a child with interstitial lung disease suggestive of surfactant deficiency. Variants in known surfactant dysfunction disorder genes were not found in trio exome sequencing. Instead, a de novo heterozygous variant in RAB5B was identified in the Ras/Rab GTPases family nucleotide binding domain, p.Asp136His. Functional studies were performed in Caenorhabditis elegans by knocking the proband variant into the conserved position (Asp135) of the ortholog, rab-5 Genetic analysis demonstrated that rab-5[Asp135His] is damaging, producing a strong dominant negative gene product. rab-5[Asp135His] heterozygotes were also defective in endocytosis and early endosome (EE) fusion. Immunostaining studies of the proband's lung biopsy revealed that RAB5B and EE marker EEA1 were significantly reduced in alveolar type II cells and that mature SP-B and SP-C were significantly reduced, while proSP-B and proSP-C were normal. Furthermore, staining normal lung showed colocalization of RAB5B and EEA1 with proSP-B and proSP-C. These findings indicate that dominant negative-acting RAB5B Asp136His and EE dysfunction cause a defect in processing/trafficking to produce mature SP-B and SP-C, resulting in interstitial lung disease, and that RAB5B and EEs normally function in the surfactant secretion pathway. Together, the data suggest a noncanonical function for RAB5B and identify RAB5B p.Asp136His as a genetic mechanism for a surfactant dysfunction disorder.


Assuntos
Variação Genética/genética , Precursores de Proteínas/genética , Proteína C Associada a Surfactante Pulmonar/genética , Proteínas Associadas a Surfactantes Pulmonares/genética , Proteínas rab5 de Ligação ao GTP/genética , Células Epiteliais Alveolares/metabolismo , Animais , Caenorhabditis elegans/genética , Humanos , Pulmão/metabolismo , Doenças Pulmonares Intersticiais/genética , Surfactantes Pulmonares/metabolismo
10.
Circulation ; 145(7): 531-548, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157519

RESUMO

BACKGROUND: Rheumatic heart valve disease (RHVD) is a leading cause of cardiovascular death in low- and middle-income countries and affects predominantly women. The underlying mechanisms of chronic valvular damage remain unexplored and regulators of sex predisposition are unknown. METHODS: Proteomics analysis of human heart valves (nondiseased aortic valves, nondiseased mitral valves [NDMVs], valves from patients with rheumatic aortic valve disease, and valves from patients with rheumatic mitral valve disease; n=30) followed by system biology analysis identified ProTα (prothymosin alpha) as a protein associated with RHVD. Histology, multiparameter flow cytometry, and enzyme-linked immunosorbent assay confirmed the expression of ProTα. In vitro experiments using peripheral mononuclear cells and valvular interstitial cells were performed using multiparameter flow cytometry and quantitative polymerase chain reaction. In silico analysis of the RHVD and Streptococcuspyogenes proteomes were used to identify mimic epitopes. RESULTS: A comparison of NDMV and nondiseased aortic valve proteomes established the baseline differences between nondiseased aortic and mitral valves. Thirteen unique proteins were enriched in NDMVs. Comparison of NDMVs versus valves from patients with rheumatic mitral valve disease and nondiseased aortic valves versus valves from patients with rheumatic aortic valve disease identified 213 proteins enriched in rheumatic valves. The expression of the 13 NDMV-enriched proteins was evaluated across the 213 proteins enriched in diseased valves, resulting in the discovery of ProTα common to valves from patients with rheumatic mitral valve disease and valves from patients with rheumatic aortic valve disease. ProTα plasma levels were significantly higher in patients with RHVD than in healthy individuals. Immunoreactive ProTα colocalized with CD8+ T cells in RHVD. Expression of ProTα and estrogen receptor alpha correlated strongly in circulating CD8+ T cells from patients with RHVD. Recombinant ProTα induced expression of the lytic proteins perforin and granzyme B by CD8+ T cells as well as higher estrogen receptor alpha expression. In addition, recombinant ProTα increased human leukocyte antigen class I levels in valvular interstitial cells. Treatment of CD8+ T cells with specific estrogen receptor alpha antagonist reduced the cytotoxic potential promoted by ProTα. In silico analysis of RHVD and Spyogenes proteomes revealed molecular mimicry between human type 1 collagen epitope and bacterial collagen-like protein, which induced CD8+ T-cell activation in vitro. CONCLUSIONS: ProTα-dependent CD8+ T-cell cytotoxicity was associated with estrogen receptor alpha activity, implicating ProTα as a potential regulator of sex predisposition in RHVD. ProTα facilitated recognition of type 1 collagen mimic epitopes by CD8+ T cells, suggesting mechanisms provoking autoimmunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Colágeno Tipo I/metabolismo , Receptor alfa de Estrogênio/metabolismo , Doenças das Valvas Cardíacas/etiologia , Doenças das Valvas Cardíacas/metabolismo , Precursores de Proteínas/metabolismo , Timosina/análogos & derivados , Sequência de Aminoácidos , Colágeno Tipo I/química , Biologia Computacional/métodos , Suscetibilidade a Doenças , Epitopos de Linfócito T/imunologia , Doenças das Valvas Cardíacas/diagnóstico , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Modelos Biológicos , Modelos Moleculares , Ligação Proteica , Precursores de Proteínas/química , Precursores de Proteínas/genética , Proteoma , Proteômica/métodos , Cardiopatia Reumática/diagnóstico , Cardiopatia Reumática/etiologia , Cardiopatia Reumática/metabolismo , Relação Estrutura-Atividade , Timosina/química , Timosina/genética , Timosina/metabolismo
11.
Rapid Commun Mass Spectrom ; 36(6): e9251, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34978114

RESUMO

RATIONALE: A large number of studies have shown that the production of aberrant and deleterious copper zinc superoxide dismutase (SOD1) species is closely related to amyotrophic lateral sclerosis (ALS). Therefore, it is of great significance to screen effective inhibitors of misfolding and aggregation of SOD1 for treating ALS disease. METHODS: The interaction between flavanone compounds with apo-SOD1was investigated using native electrospray ion mobility mass spectrometry (native ESI-IM-MS). Binding affinities of ligands were compared using native MS, ESI-MS/MS, collision-induced unfolding, and competitive experiments. The effect of ligands on apo-SOD1 aggregation was investigated using the fluorescence spectroscopy method. RESULTS: The results of MS showed that the binding affinity of liquiritin apioside was the strongest, better than the corresponding monosaccharide and aglycone, indicating that the presence and the number of glycosyl group are beneficial to enhance ligand affinity to protein. The results of fluorescence spectroscopy for inhibiting protein aggregation in vitro were consistent with the binding affinity. In addition, the results of the collision-induced unfolding indicated that liquiritin apioside can slow down the unfolding of the protein. Meanwhile, the results of competition experiment suggested that liquiritin apiosides share different binding sites with naringin and 5-fluorouridine, which are significant for the structural stability of SOD1. CONCLUSIONS: This study revealed that the binding of liquiritin apioside can stabilize apo-SOD1 dimer and inhibit the aggregation of apo-SOD1, and illustrated that native ESI-IM-MS is a powerful tool for providing insight into investigating the structure-activity relationship between small molecules and protein, and screening protein conformation stabilizers.


Assuntos
Flavanonas/química , Espectrometria de Mobilidade Iônica/métodos , Precursores de Proteínas/química , Espectrometria de Fluorescência/métodos , Superóxido Dismutase-1/química , Sítios de Ligação , Dimerização , Humanos , Cinética , Agregados Proteicos , Conformação Proteica , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Estabilidade Proteica , Superóxido Dismutase-1/metabolismo
12.
J Virol ; 96(5): e0172321, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35019714

RESUMO

Hepatitis B virus (HBV) large (L) envelope protein is translated from 2.4-kb RNA. It contains preS1, preS2, and S domains and is detected in Western blotting as p39 and gp42. The 3.5-kb pregenomic RNA produces core and polymerase (P) proteins. We generated L-minus mutants of a genotype A clone and a genotype D clone from 1.1-mer or 1.3-mer construct, with the former overproducing pregenomic RNA. Surprisingly, mutating a preS1 ATG codon(s) or introducing a nonsense mutation soon afterwards switched secreted p39/gp42 to a p41/p44 doublet, with its amount further increased by a nonsense mutation in the core gene. A further-downstream preS1 nonsense mutation prevented p41/p44 production. Tunicamycin treatment confirmed p44 as the glycosylated form of p41. In this regard, splicing of 3.5-kb RNA to generate a junction at nucleotides (nt) 2447 to 2902 for genotype D enables translation of p43, with the N-terminal 47 residues of P protein fused to the C-terminal 371 residues of L protein. Indeed p41/p44 were detectable by an antibody against the N terminus of P protein and eliminated by a nonsense mutation at the 5' P gene or a point mutation to prevent that splicing. Therefore, lost L (and core) protein expression from the 1.1-mer or 1.3-mer construct markedly increased p41/p44 (p43), the P-L fusion protein. Cotransfection with an expression construct for L/M proteins reversed high extracellular p41/p44 associated with L-minus mutants, suggesting that L protein retains p43 in wild-type HBV to promote its intracellular degradation. Considering that p43 lacks N-terminal preS1 sequence critical for receptor binding, its physiological significance during natural infection and therapeutic potential warrant further investigation. IMPORTANCE The large (L) envelope protein of hepatitis B virus (HBV) is translated from 2.4-kb RNA and detected in Western blotting as p39 and gp42. Polymerase (P) protein is expressed at a low level from 3.5-kb RNA. The major spliced form of 3.5-kb RNA will produce a fusion protein between the first 47 residues of P protein and a short irrelevant sequence, although also at a low level. Another spliced form has the same P protein sequence fused to L protein missing its first 18 residues. We found that some point mutations to eliminate L and core protein expression from overlength HBV DNA constructs converted p39/gp42 to p41/gp44, which turned out to be the P-L fusion protein. Thus, the P-L fusion protein can be expressed at extremely high level when L protein expression is prevented. The underlying mechanism and functional significance of this variant form of L protein warrant further investigation.


Assuntos
Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Herpesvirus Cercopitecino 1 , Precursores de Proteínas , Proteínas do Envelope Viral , Proteínas Virais de Fusão , Códon sem Sentido/metabolismo , Genótipo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Herpesvirus Cercopitecino 1/genética , Humanos , Mutação , Precursores de Proteínas/genética , Proteínas do Envelope Viral/genética , Proteínas Virais de Fusão/genética
13.
Microb Cell Fact ; 21(1): 11, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033086

RESUMO

BACKGROUND: The bacteriocin nisin is naturally produced by Lactococcus lactis as an inactive prepeptide that is modified posttranslationally resulting in five (methyl-)lanthionine rings characteristic for class Ia bacteriocins. Export and proteolytic cleavage of the leader peptide results in release of active nisin. By targeting the universal peptidoglycan precursor lipid II, nisin has a broad target spectrum including important human pathogens such as Listeria monocytogenes and methicillin-resistant Staphylococcus aureus strains. Industrial nisin production is currently performed using natural producer strains resulting in rather low product purity and limiting its application to preservation of dairy food products. RESULTS: We established heterologous nisin production using the biotechnological workhorse organism Corynebacterium glutamicum in a two-step process. We demonstrate successful biosynthesis and export of fully modified prenisin and its activation to mature nisin by a purified, soluble variant of the nisin protease NisP (sNisP) produced in Escherichia coli. Active nisin was detected by a L. lactis sensor strain with strictly nisin-dependent expression of the fluorescent protein mCherry. Following activation by sNisP, supernatants of the recombinant C. glutamicum producer strain cultivated in standard batch fermentations contained at least 1.25 mg/l active nisin. CONCLUSIONS: We demonstrate successful implementation of a two-step process for recombinant production of active nisin with C. glutamicum. This extends the spectrum of bioactive compounds that may be produced using C. glutamicum to a bacteriocin harboring complex posttranslational modifications. Our results provide a basis for further studies to optimize product yields, transfer production to sustainable substrates and purification of pharmaceutical grade nisin.


Assuntos
Corynebacterium glutamicum/metabolismo , Nisina/biossíntese , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/crescimento & desenvolvimento , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Nisina/química , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Precursores de Proteínas/biossíntese , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo , Tripsina/metabolismo
14.
RNA ; 28(3): 371-389, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34934010

RESUMO

The two subunits of the eukaryotic ribosome are produced through quasi-independent pathways involving the hierarchical actions of numerous trans-acting biogenesis factors and the incorporation of ribosomal proteins. The factors work together to shape the nascent subunits through a series of intermediate states into their functional architectures. One of the earliest intermediates of the small subunit (SSU or 40S) is the SSU processome which is subsequently transformed into the pre-40S intermediate. This transformation is, in part, facilitated by the binding of the methyltransferase Bud23. How Bud23 is released from the resultant pre-40S is not known. The ribosomal proteins Rps0, Rps2, and Rps21, termed the Rps0-cluster proteins, and several biogenesis factors bind the pre-40S around the time that Bud23 is released, suggesting that one or more of these factors could induce Bud23 release. Here, we systematically examined the requirement of these factors for the release of Bud23 from pre-40S particles. We found that the Rps0-cluster proteins are needed but not sufficient for Bud23 release. The atypical kinase/ATPase Rio2 shares a binding site with Bud23 and is thought to be recruited to pre-40S after the Rps0-cluster proteins. Depletion of Rio2 prevented the release of Bud23 from the pre-40S. More importantly, the addition of recombinant Rio2 to pre-40S particles affinity-purified from Rio2-depleted cells was sufficient for Bud23 release in vitro. The ability of Rio2 to displace Bud23 was independent of nucleotide hydrolysis. We propose a novel role for Rio2 in which its binding to the pre-40S actively displaces Bud23 from the pre-40S.


Assuntos
Metiltransferases/metabolismo , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Metiltransferases/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/genética
15.
Tissue Barriers ; 10(3): 2000299, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34775911

RESUMO

The gut-brain axis hypothesis suggests that interactions in the intestinal milieu are critically involved in regulating brain function. Several studies point to a gut-microbiota-brain connection linking an impaired intestinal barrier and altered gut microbiota composition to neurological disorders involving neuroinflammation. Increased gut permeability allows luminal antigens to cross the gut epithelium, and via the blood stream and an impaired blood-brain barrier (BBB) enters the brain impacting its function. Pre-haptoglobin 2 (pHP2), the precursor protein to mature HP2, is the first characterized member of the zonulin family of structurally related proteins. pHP 2 has been identified in humans as the thus far only endogenous regulator of epithelial and endothelial tight junctions (TJs). We have leveraged the Zonulin-transgenic mouse (Ztm) that expresses a murine pHP2 (zonulin) to determine the role of increased gut permeability and its synergy with a dysbiotic intestinal microbiota on brain function and behavior. Here we show that Ztm mice display sex-dependent behavioral abnormalities accompanied by altered gene expression of BBB TJs and increased expression of brain inflammatory genes. Antibiotic depletion of the gut microbiota in Ztm mice downregulated brain inflammatory markers ameliorating some anxiety-like behavior. Overall, we show that zonulin-dependent alterations in gut permeability and dysbiosis of the gut microbiota are associated with an altered BBB integrity, neuroinflammation, and behavioral changes that are partially ameliorated by microbiota depletion. Our results suggest the Ztm model as a tool for the study of the cross-talk between the microbiome/gut and the brain in the context of neurobehavioral/neuroinflammatory disorders.


Assuntos
Comportamento Animal , Barreira Hematoencefálica , Microbioma Gastrointestinal , Haptoglobinas , Animais , Disbiose/fisiopatologia , Haptoglobinas/genética , Humanos , Mucosa Intestinal/fisiopatologia , Camundongos , Camundongos Transgênicos , Precursores de Proteínas/genética
16.
J Mol Biol ; 434(2): 167350, 2022 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-34774568

RESUMO

Maturation of adenoviruses is distinguished by proteolytic processing of several interior minor capsid proteins and core proteins by the adenoviral protease and subsequent reorganization of adenovirus core. We report the results derived from the icosahedrally averaged cryo-EM structure of a cell entry defective form of adenovirus, designated ts1, at a resolution of 3.7 Å as well as of the localized reconstructions of unique hexons and penton base. The virion structure revealed the structures and organization of precursors of minor capsid proteins, pIIIa, pVI and pVIII, which are closely associated with the hexons on the capsid interior. In addition to a well-ordered helical domain (a.a. 310-397) of pIIIa, highlights of the structure include the precursors of VIII display significantly different structures near the cleavage sites. Moreover, we traced residues 4-96 of the membrane lytic protein (pVI) that includes an amphipathic helix occluded deep in the hexon cavity suggesting the possibility of co-assembly of hexons with the precursors of VI. In addition, we observe a second copy of pVI ordered up to residue L40 in the peripentonal hexons and a few fragments of density corresponding to 2nd and 3rd copies of pVI in other hexons. However, we see no evidence of precursors of VII binding in the hexon cavity. These findings suggest the possibility that differently bound pVI molecules undergo processing at the N-terminal cleavage sites at varying efficiencies, subsequently creating competition between the cleaved and uncleaved forms of VI, followed by reorganization, processing, and release of VI molecules from the hexon cavities.


Assuntos
Adenovírus Humanos/fisiologia , Proteínas do Capsídeo/química , Capsídeo/química , Precursores de Proteínas/genética , Internalização do Vírus , Humanos , Modelos Moleculares , Conformação Proteica , Vírion/metabolismo , Montagem de Vírus
17.
J Ethn Subst Abuse ; 21(2): 522-537, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32597371

RESUMO

Aim of the study is to compare prodynorphin (PDYN) rs1997794, rs1022563, rs6045819, rs2235749 polymorphisms in individuals with methamphetamine use disorder (MD) to that of healthy controls (HC), and to investigate the differences in serum PDYN levels in methamphetamine withdrawal. It is also aimed to explore the temperament characteristics and depression and their relationship with PDYN polymorphisms and PDYN serum levels in MD group. PDYN gene and serum levels were studied in 134 patients with MD and 97 HC. Patients with MD were administered Beck Depression Inventory (BDI) and Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A). For rs1022563 polymorphism, TT and CT genotype frequency and T allele frequency were significantly higher in the MD group than the frequencies in HC. It was found that rs2235749 polymorphism AA genotype was associated with increased risk of MD. PDYN rs1997794 CT genotypes had significantly higher scores of TEMPS-A irritable than CC genotypes and PDYN rs1022563 CC genotypes had significantly higher scores of TEMPS-A irritable than TT genotypes. PDYN levels among persons with MD were significantly higher than among the HC group when the withdrawal level increased and withdrawal symptoms improved. During the period in which the withdrawal level increased, there was a negative correlation between PDYN level and BDI and a positive relationship between PDYN level and TEMPS-A hyperthymic. It may be beneficial to screen temperament characteristics associated with increased risk of addiction in patients with MD and develop interventions based on temperament characteristics and the effects of PDYN.


Assuntos
Encefalinas/genética , Metanfetamina , Precursores de Proteínas/genética , Transtornos Relacionados ao Uso de Substâncias/genética , Depressão/genética , Encefalinas/sangue , Encefalinas/metabolismo , Humanos , Inventário de Personalidade , Polimorfismo Genético , Precursores de Proteínas/sangue , Precursores de Proteínas/metabolismo , Psicometria , Inquéritos e Questionários , Temperamento , Turquia
18.
J Autism Dev Disord ; 52(10): 4213-4218, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34562210

RESUMO

The aim of the study was to perform family-based association analysis of PRKCB1, CBLN1 and KCNMB4 gene polymorphisms and autism disorder. We comprised 206 Caucasian children with autistic spectrum disorder (ASD) and their biological parents. In transmission/disequilibrium test we observed that T-allele of the rs198198 polymorphism of the PRKCB1 gene was more often transmitted to affected children in the male subgroup (p = 0.010). Additionally, the T carrier state was significantly associated with hypotonia (p = 0.048). In the female subgroup, the T-allele carriers more often showed more mobile/vital behavior (p = 0.046). In conclusion, our study showed that the rs198198 of the PRKCB1 gene may be associated with ASD in men and with some features characteristic for the disorder.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Proteínas do Tecido Nervoso/genética , Proteína Quinase C beta/genética , Precursores de Proteínas/genética , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Criança , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Humanos , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Masculino , Proteínas do Tecido Nervoso/metabolismo , Polônia , Polimorfismo de Nucleotídeo Único
19.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34884858

RESUMO

The melanocortin system is a major regulator of stress responses in the skin and is responsible for the induction of melanin synthesis through activation of melanogenesis enzymes. The expression of both melanocortin system genes and melanogenesis enzyme genes is altered in psoriasis, and the focus here was on twelve genes related to the signal transduction between them. Additionally, five endogenous opioid system genes that are involved in cutaneous inflammation were examined. Quantitative real-time-PCR was utilized to measure mRNA expression in punch biopsies from lesional and non-lesional skin of psoriasis patients and from the skin of healthy control subjects. Most of the genes related to melanogenesis were down-regulated in patients (CREB1, MITF, LEF1, USF1, MAPK14, ICAM1, PIK3CB, RPS6KB1, KIT, and ATRN). Conversely, an up-regulation occurred in the case of opioids (PENK, PDYN, and PNOC). The suppression of genes related to melanogenesis is in agreement with the reported reduction in pigmentation signaling in psoriatic skin and potentially results from the pro-inflammatory environment. The increase in endogenous opioids can be associated with their involvement in inflammatory dysregulation in psoriasis.


Assuntos
Psoríase/genética , Psoríase/patologia , Pigmentação da Pele/genética , Adolescente , Adulto , Analgésicos Opioides/metabolismo , Biópsia , Estudos de Casos e Controles , Classe I de Fosfatidilinositol 3-Quinases/genética , Encefalinas/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Fator de Transcrição Associado à Microftalmia/genética , Precursores de Proteínas/genética , Receptores Opioides/genética , Pele/patologia , Adulto Jovem , Receptor de Nociceptina
20.
Mol Metab ; 54: 101366, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34728342

RESUMO

OBJECTIVE: The regulation of food intake is a major research area in the study of obesity, which plays a key role in the development of metabolic syndrome. Gene targeting studies have clarified the roles of hypothalamic neurons in feeding behavior, but the deletion of a gene has a long-term effect on neurophysiology. Our understanding of short-term changes such as appetite under physiological conditions is therefore still limited. METHODS: Targeted recombination in active populations (TRAP) is a newly developed method for labeling active neurons by using tamoxifen-inducible Cre recombination controlled by the promoter of activity-regulated cytoskeleton-associated protein (Arc/Arg3.1), a member of immediate early genes. Transgenic mice for TRAP were fasted overnight, re-fed with normal diet, and injected with 4-hydroxytamoxifen 1 h after the refeeding to label the active neurons. The role of labeled neurons was examined by expressing excitatory or inhibitory designer receptors exclusively activated by designer drugs (DREADDs). The labeled neurons were extracted and RNA sequencing was performed to identify genes that are specifically expressed in these neurons. RESULTS: Fasting-refeeding activated and labeled neurons in the compact part of the dorsomedial hypothalamus (DMH) that project to the paraventricular hypothalamic nucleus. Chemogenetic activation of the labeled DMH neurons decreased food intake and developed place preference, an indicator of positive valence. Chemogenetic activation or inhibition of these neurons had no influence on the whole-body glucose metabolism. The labeled DMH neurons expressed prodynorphin (pdyn), gastrin-releasing peptide (GRP), cholecystokinin (CCK), and thyrotropin-releasing hormone receptor (Trhr) genes. CONCLUSIONS: We identified a novel cell type of DMH neurons that can inhibit food intake and promote feeding-induced positive valence. Our study provides insight into the role of DMH and its molecular mechanism in the regulation of appetite and emotion.


Assuntos
Núcleo Hipotalâmico Dorsomedial/metabolismo , Ingestão de Alimentos , Neurônios/metabolismo , Animais , Colecistocinina/genética , Encefalinas/genética , Comportamento Alimentar , Masculino , Camundongos , Camundongos Transgênicos , Precursores de Proteínas/genética
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