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1.
J Clin Immunol ; 44(7): 160, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990428

RESUMO

BACKGROUND: Inborn errors of immunity (IEIs) encompass various diseases with diverse clinical and immunological symptoms. Determining the genotype-phenotype of different variants in IEI entity precisely is challenging, as manifestations can be heterogeneous even in patients with the same mutated gene. OBJECTIVE: In the present study, we conducted a systematic review of patients recorded with NFKB1 and NFKB2 mutations, two of the most frequent monogenic IEIs. METHODS: The search for relevant literature was conducted in databases including Web of Science, PubMed, and Scopus. Information encompassing demographic, clinical, immunological, and genetic data was extracted from cases reported with mutations in NFKB1 and NFKB2. The comprehensive features of manifestations in patients were described, and a comparative analysis of primary characteristics was conducted between individuals with NFKB1 loss of function (LOF) and NFKB2 (p52-LOF/IκBδ-gain of function (GOF)) variants. RESULTS: A total of 397 patients were included in this study, 257 had NFKB1 mutations and 140 had NFKB2 mutations. There were 175 LOF cases in NFKB1 and 122 p52LOF/IκBδGOF cases in NFKB2 pivotal groups with confirmed functional implications. NFKB1LOF and p52LOF/IκBδGOF predominant cases (81.8% and 62.5% respectively) initially presented with a CVID-like phenotype. Patients with NFKB1LOF variants often experienced hematologic autoimmune disorders, whereas p52LOF/IκBδGOF patients were more susceptible to other autoimmune diseases. Viral infections were markedly higher in p52LOF/IκBδGOF cases compared to NFKB1LOF (P-value < 0.001). NFKB2 (p52LOF/IκBδGOF) patients exhibited a greater prevalence of ectodermal dysplasia and pituitary gland involvement than NFKB1LOF patients. Most NFKB1LOF and p52LOF/IκBδGOF cases showed low CD19 + B cells, with p52LOF/IκBδGOF having more cases of this type. Low memory B cells were more common in p52LOF/IκBδGOF patients. CONCLUSIONS: Patients with NFKB2 mutations, particularly p52LOF/IκBδGOF, are at higher risk of viral infections, pituitary gland involvement, and ectodermal dysplasia compared to patients with NFKB1LOF mutations. Genetic testing is essential to resolve the initial complexity and confusion surrounding clinical and immunological features. Emphasizing the significance of functional assays in determining the probability of correlations between mutations and immunological and clinical characteristics of patients is crucial.


Assuntos
Mutação , Subunidade p50 de NF-kappa B , Subunidade p52 de NF-kappa B , Humanos , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação/genética , Subunidade p50 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/genética , Fenótipo
2.
J Toxicol Environ Health A ; 87(4): 150-165, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38037686

RESUMO

Ammi visnaga (A. visnaga) is an annual herb that has been used in traditional medicine to treat various ailments attributed to the presence of its bioactive compounds. The purpose of this study was to identify and examine the phytochemical properties of the hydroalcoholic extract of A. visnaga using in vitro and in vivo models. Our findings demonstrated that the extract contained a variety of beneficial components, including phenols, flavonoids, tannins, coumarins, saponins, khellin, and visnagin. The total polyphenolic content and total flavonoid content were 23.26 mg/GAE/g dry weight and 13.26 mg/GAE/g dry weight, respectively. In vitro tests demonstrated that the extract possessed antioxidant properties as evidenced by the ability to scavenge free radicals, including DPPH, ABTS, nitric oxide (NO), phosphomolybdate, and ferric-reducing antioxidant power (FRAP). Further, the extract was found to inhibit hydrogen peroxide (H2O2)-induced hemolysis. In a 90-d in vivo study, female Wistar rats were administered 1 g/kg of A. visnaga extract orally resulting in a significant increase in total white blood cell count. Although morphological changes were observed in the liver, no marked alterations were noted in kidneys and spleen. In a female Swiss albino mice model of acetic acid-induced vascular permeability, A. visnaga significantly inhibited extravasations of Evans blue at doses of 0.5 or 1 g/kg with inhibition percentages of 51 and 65%, respectively, blocking tissue necrosis. The extract also demonstrated potential immunomodulatory properties in mice by enhancing antibody production in response to antigens. In silico molecular docking studies demonstrated a strong affinity between khellin or visnagin and immunomodulatory proteins, NF-κB, p52, and TNF-α. These findings suggest that A. visnaga may be considered a beneficial antioxidant with immunomodulatory properties and might serve as a therapeutic agent to combat certain diseases.


Assuntos
Ammi , Quelina , Ratos , Feminino , Camundongos , Animais , Extratos Vegetais/química , Ammi/química , Quelina/química , Quelina/farmacologia , Antioxidantes/farmacologia , Peróxido de Hidrogênio , Simulação de Acoplamento Molecular , Ratos Wistar , Flavonoides/farmacologia , Anti-Inflamatórios/farmacologia
3.
Int J Mol Sci ; 25(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39337282

RESUMO

The Nuclear Factor Kappa B (NF-κB) transcription factor family consists of five members: RelA (p65), RelB, c-Rel, p50 (p105/NF-κB1), and p52 (p100/NF-κB2). This family is considered a master regulator of classical biochemical pathways such as inflammation, immunity, cell proliferation, and cell death. The proteins in this family have a conserved Rel homology domain (RHD) with the following subdomains: DNA binding domain (RHD-DBD) and dimerization domain (RHD-DD). Despite the importance of the NF-κB family in biology, there is a lack of information with respect to their distribution patterns, evolution, and structural conservation concerning domains and subdomains in animals. This study aims to address this critical gap regarding NF-κB proteins. A comprehensive analysis of NF-κB family proteins revealed their distinct distribution in animals, with differences in protein sizes, conserved domains, and subdomains (RHD-DBD and RHD-DD). For the first time, NF-κB proteins with multiple RHD-DBDs and RHD-DDs have been identified, and in some cases, this is due to subdomain duplication. The presence of RelA/p65 exclusively in vertebrates shows that innate immunity originated in fishes, followed by amphibians, reptiles, aves, and mammals. Phylogenetic analysis showed that NF-κB family proteins grouped according to animal groups, signifying structural conservation after speciation. The evolutionary analysis of RHDs suggests that NF-κB family members p50/p105 and c-Rel may have been the first to emerge in arthropod ancestors, followed by RelB, RelA, and p52/p100.


Assuntos
Evolução Molecular , NF-kappa B , Animais , Sequência Conservada , NF-kappa B/metabolismo , Filogenia , Domínios Proteicos
4.
J Biol Chem ; 298(10): 102433, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36041630

RESUMO

TFIIH is an evolutionarily conserved complex that plays central roles in both RNA polymerase II (pol II) transcription and DNA repair. As an integral component of the pol II preinitiation complex, TFIIH regulates pol II enzyme activity in numerous ways. The TFIIH subunit XPB/Ssl2 is an ATP-dependent DNA translocase that stimulates promoter opening prior to transcription initiation. Crosslinking-mass spectrometry and cryo-EM results have shown a conserved interaction network involving XPB/Ssl2 and the C-terminal Hub region of the TFIIH p52/Tfb2 subunit, but the functional significance of specific residues is unclear. Here, we systematically mutagenized the HubA region of Tfb2 and screened for growth phenotypes in a TFB6 deletion background in Saccharomyces cerevisiae. We identified six lethal and 12 conditional mutants. Slow growth phenotypes of all but three conditional mutants were relieved in the presence of TFB6, thus identifying a functional interaction between Tfb2 HubA mutants and Tfb6, a protein that dissociates Ssl2 from TFIIH. Our biochemical analysis of Tfb2 mutants with severe growth phenotypes revealed defects in Ssl2 association, with similar results in human cells. Further characterization of these tfb2 mutant cells revealed defects in GAL gene induction, and reduced occupancy of TFIIH and pol II at GAL gene promoters, suggesting that functionally competent TFIIH is required for proper pol II recruitment to preinitiation complexes in vivo. Consistent with recent structural models of TFIIH, our results identify key residues in the p52/Tfb2 HubA domain that are required for stable incorporation of XPB/Ssl2 into TFIIH and for pol II transcription.


Assuntos
DNA Helicases , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Fator de Transcrição TFIIH , Humanos , DNA Helicases/genética , DNA Helicases/metabolismo , Reparo do DNA , Mutagênese , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fator de Transcrição TFIIH/genética , Fator de Transcrição TFIIH/metabolismo , Transcrição Gênica
5.
Acta Pharmacol Sin ; 44(3): 647-660, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35995868

RESUMO

Targeting MDM2-p53 interaction has emerged as a promising antitumor therapeutic strategy. Several MDM2-p53 inhibitors have advanced into clinical trials, but results are not favorable. The lack of appropriate biomarkers for selecting patients has been assumed as the critical reason for this failure. We previously identified ZER6 isoform p52-ZER6 as an oncogene upregulated in tumor tissues. In this study we investigated whether p52-ZER6 acted as a blocker of MDM2-p53 binding inhibitors, and whether p52-ZER6 could be used as a biomarker of MDM2-p53 binding inhibitors. In p53 wild-type colorectal carcinoma HCT116, hepatocarcinoma HepG2 and breast cancer MCF-7 cells, overexpression of p52-ZER6 enhanced MDM2-p53 binding and promoted p53 ubiquitination/proteasomal degradation. Furthermore, overexpression of p52-ZER6 in the tumor cells dose-dependently reduced their sensitivity to both nutlin and non-nutlin class MDM2-p53 binding inhibitors. We showed that p52-ZER6 restored tumor cell viability, which was suppressed by nutlin-3, through restoring their proliferation potential while suppressing their apoptotic rate, suggesting that MDM2-p53 binding inhibitors might not be effective for patients with high p52-ZER6 levels. We found that nutlin-3 treatment or p52-ZER6 knockdown alone promoted the accumulation of p53 protein in the tumor cells, and their combinatorial treatment significantly increased the accumulation of p53 protein. In HCT116 cell xenograft nude mouse model, administration of shp52-ZER6 combined with an MDM2-p53 binding inhibitor nutlin-3 exerted synergistic antitumor response. In conclusion, this study reveals that p52-ZER6 might be a potential biomarker for determining patients appropriate for MDM2-p53 binding inhibition-based antitumor therapy, and demonstrates the potential of combinatorial therapy using MDM2-p53 binding inhibitors and p52-ZER6 inhibition.


Assuntos
Antineoplásicos , Proteínas Proto-Oncogênicas c-mdm2 , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Apoptose , Biomarcadores , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo
6.
Phytother Res ; 37(7): 2939-2956, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36938853

RESUMO

This study investigated antimalarial efficacy and sensitization of chrysosplenetin against artemisinin-resistant Plasmodium berghei K173 and potential molecular mechanism. Our data indicated a risk of artemisinin resistance because a higher parasitaemia% and lower inhibition% under artemisinin treatment against resistant parasites than those in the sensitive groups were observed. Two non-antimalarial components, verapamil and chrysosplentin, being P-gp inhibitors, possessed a strong efficacy against resistant parasites but it was not the case for Bcrp inhibitor novobiocin. Artemisinin-chrysosplenetin combination improved artemisinin susceptibility of resistant P. berghei. Artemisinin activated intestinal P-gp and Abcb1/Abcg2 expressions and suppressed Bcrp whereas chrysosplenetin reversed them. Resistant parasite infection led to a decreased haemozoin in organs or an increased heme in peripheral bloods compared with the sensitives; however, that in Abcb1-deficient knockout (KO)-resistant mice reversely got increased or decreased versus wild type (WT)-resistant animals. Chrysosplenetin as well as rifampin (nuclear receptor agonist) increased the transcription levels of PXR/CAR while showed a versatile regulation on hepatic and enternal PXR/CAR in WT- or KO-sensitive or -resistant parasites. Oppositely, hepatic and enteric NF-κB p52 mRNA decreased conformably in WT but increased in KO-resistant mice. NF-κB pathway potentially involved in the mechanism of chrysosplenetin on inhibiting P-gp expressions while PXR/CAR play a more complicated role in this mechanism.


Assuntos
Antimaláricos , Artemisininas , Camundongos , Animais , Antimaláricos/farmacologia , Plasmodium berghei , Subunidade p52 de NF-kappa B/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Proteínas de Neoplasias , Artemisininas/farmacologia , Transdução de Sinais , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Homeostase , Heme/farmacologia
7.
Int J Mol Sci ; 21(8)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316320

RESUMO

Recent evidence indicates that activation of adenosine monophosphate-activated protein kinase (AMPK), a highly conserved sensor and modulator of cellular energy and redox, regulates cell mitosis. However, the underlying molecular mechanisms for AMPKα subunit regulation of chromosome segregation remain poorly understood. This study aimed to ascertain if AMPKα1 deletion contributes to chromosome missegregation by elevating Polo-like kinase 4 (PLK4) expression. Centrosome proteins and aneuploidy were monitored in cultured mouse embryonic fibroblasts (MEFs) isolated from wild type (WT, C57BL/6J) or AMPKα1 homozygous deficient (AMPKα1-/-) mice by Western blotting and metaphase chromosome spread. Deletion of AMPKα1, the predominant AMPKα isoform in immortalized MEFs, led to centrosome amplification and chromosome missegregation, as well as the consequent aneuploidy (34-66%) and micronucleus. Furthermore, AMPKα1 null cells exhibited a significant induction of PLK4. Knockdown of nuclear factor kappa B2/p52 ameliorated the PLK4 elevation in AMPKα1-deleted MEFs. Finally, PLK4 inhibition by Centrinone reversed centrosome amplification of AMPKα1-deleted MEFs. Taken together, our results suggest that AMPKα1 plays a fundamental role in the maintenance of chromosomal integrity through the control of p52-mediated transcription of PLK4, a trigger of centriole biogenesis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Centrossomo/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases Ativadas por AMP/deficiência , Proteínas Quinases Ativadas por AMP/genética , Animais , Células Cultivadas , Segregação de Cromossomos , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Subunidade p52 de NF-kappa B/antagonistas & inibidores , Subunidade p52 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Regulação para Cima
8.
Mol Carcinog ; 58(5): 777-793, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30604907

RESUMO

Although overexpression of the non-canonical NFκB subunit p52 has been observed in several tumors, the function and mechanism of p52 in bladder cancer (BC) are less well understood. Here, we aimed at understanding the role and mechanism underlying p52 regulation of BC invasion. Human p52 was stably knockdown with shRNA targeting p52 in two bladder cancer cell lines (T24 and UMUC3). Two constitutively expressing constructs, p52 and p100, were stably transfected in to T24 or UMUC3, respectively. The stable transfectants were used to determine function and mechanisms responsible for p52 regulation of BC invasion. We demonstrate that p52 mediates human BC invasion. Knockdown of p52 impaired bladder cancer invasion by reduction of rhogdiß mRNA stability and expression. Positively regulation of rhogdiß mRNA stability was mediated by p52 promoting AUF1 protein degradation, consequently resulting in reduction of AUF1 binding to rhogdiß mRNA. Further studies indicated that AUF1 protein degradation was mediated by upregulating USP8 transcription, which was modulated by its negative regulatory transcription factor Sp1. Moreover, we found that p52 upregulated miR-145, which directly bound to the 3'-UTR of sp1 mRNA, leading to downregulation of Sp1 protein translation. Our results reveal a comprehensive pathway that p52 acts as a positive regulator of BC invasion by initiating a novel miR-145/Sp1/USP8/AUF1/RhoGDIß axis. These findings provide insight into the understanding of p52 in the pathology of human BC invasion and progression, which may be useful information in the development of preventive and therapeutic approaches for using p52 as a potential target.


Assuntos
Endopeptidases/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , MicroRNAs/metabolismo , Subunidade p52 de NF-kappa B/metabolismo , Estabilidade de RNA , Fator de Transcrição Sp1/metabolismo , Ubiquitina Tiolesterase/metabolismo , Neoplasias da Bexiga Urinária/patologia , Inibidor beta de Dissociação do Nucleotídeo Guanina rho/metabolismo , Endopeptidases/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Regulação Neoplásica da Expressão Gênica , Ribonucleoproteína Nuclear Heterogênea D0 , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/genética , Humanos , MicroRNAs/genética , Subunidade p52 de NF-kappa B/genética , Biossíntese de Proteínas , Proteólise , Fator de Transcrição Sp1/genética , Células Tumorais Cultivadas , Ubiquitina Tiolesterase/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Inibidor beta de Dissociação do Nucleotídeo Guanina rho/química , Inibidor beta de Dissociação do Nucleotídeo Guanina rho/genética
9.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3365-3377, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27590109

RESUMO

BACKGROUND: Chemokines play key roles in immune homeostasis and inflammatory response. Considering the role of Ccl20 and Toll-like receptor 9 (TLR9) in gut homeostasis and inflammatory bowel disease (IBD), regulation of Ccl20 by bacterial DNA, the TLR9 ligand, merits in-depth studies. METHODS: We analyzed Ccl20 expression in various epithelial cell (EC) lines by q-PCR and ELISA. In-vivo expression was investigated in isolated murine colonocytes by immunoblotting. Transcriptional regulation of Ccl20 was studied by reporter assays, gene knock-down, electrophoretic mobility shift assay and chromatin immunoprecipitation. Activation of upstream kinases was checked by immunoblotting. RESULTS: We showed low levels of Ccl20 expression in mouse colonic ECs, but marked induction by in vivo treatment with bacterial DNA. This corroborated with persistent Ccl20 induction in different EC lines. We found involvement of MAP-kinases during the early hours after stimulation, and a novel AP-1site (-252bp) regulated the expression in colonic ECs. More importantly, mutually exclusive transcriptional regulation by AP-1 (cjun/cfos) and non-canonical NF-κB (RelB/p52) downstream of MEK-ERK and NIK-IKK-α-NF-κB2 (p100) phosphorylation, respectively was responsible for persistent Ccl20 expression in the colonic cells, while canonical NF-κB isoforms played no role. CONCLUSIONS: Persistent Ccl20 induction by TLR9 in colonic ECs involves early and delayed activation of two independent signaling pathways. This is the first report of non-canonical NF-κB activation and Ccl20 expression in the colonic ECs by TLR9. GENERAL SIGNIFICANCE: Our study will help to better understand immune regulation by Ccl20 in the intestine and may be exploited for future development of novel therapeutics against IBD.


Assuntos
Quimiocina CCL20/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor Toll-Like 9/metabolismo , Fator de Transcrição AP-1/metabolismo , Animais , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Quimiocina CCL20/metabolismo , Quimiotaxia/efeitos dos fármacos , DNA Bacteriano/farmacologia , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Modelos Biológicos , Fator 88 de Diferenciação Mieloide/metabolismo , Subunidades Proteicas/metabolismo , Transporte Proteico/efeitos dos fármacos , Fator 6 Associado a Receptor de TNF/metabolismo , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
10.
Virus Genes ; 52(1): 4-13, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26739459

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is a causative retrovirus of adult T-cell leukemia and HTLV-1-associated myelopathy. Unlike HTLV-1, the same group of retrovirus HTLV-2 has not been found to be associated with these diseases. HTLV-1 and HTLV-2 encode transforming proteins Tax1 and Tax2, and a few distinct activities of Tax1 from those of Tax2 have been proposed to contribute to the HTLV-1-specific pathogenesis of disease. One significant difference of Tax1 from Tax2 is the activation of transcription factor NF-κB2/p100/p52. We found that Tax1 but not Tax2 induces the expression of OX40 ligand (OX40L) in a human T-cell line. To induce the OX40L expression, Tax1 but not Tax2 was observed to interact with NF-κB2/p100/p52 and RelB and the distinct interaction activity was mediated by the Tax1 amino acid region of 225-232. In addition, Tax1 but not Tax2 or Tax1/225-232 interacted with p65, p50, and c-Rel; however, the interactions were much less than those noted with NF-κB2/p100/p52 and RelB. OX40L is a T-cell costimulatory molecule of the tumor necrosis factor family, and its signal plays a critical role in establishing adaptive immunity by inducing the polarized differentiation of T-cells to cells such as T helper type 2 and T follicular helper cells. Therefore, the present findings suggest that Tax1 might alter the immune response to HTLV-1 and/or differentiation of HTLV-1-infected T-cells via OX40L induction, thereby acting as a factor mediating the distinct phenotypes and pathogenesis of HTLV-1 from that of HTLV-2.


Assuntos
Produtos do Gene tax/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Vírus Linfotrópico T Tipo 2 Humano/fisiologia , Subunidade p52 de NF-kappa B/metabolismo , Ligante OX40/biossíntese , Células HEK293 , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Humanos , Células Jurkat , Linfócitos T/imunologia , Linfócitos T/virologia
11.
Biomol NMR Assign ; 18(2): 135-138, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38856960

RESUMO

NF-kappaB is a family of inducible transcription factors playing an important role in immune response in vertebrates. All the five members of the family function as dimers in various combinations. Though all the family members recognize and bind to similar DNA elements to regulate the transcription of its target genes, the dimer composition can lead to differential transcriptional outcomes. Here we report the backbone resonance assignment of the 24.2 kDa homodimer of p52 subunit of the NF-kB family. The p52 subunit of NF-kB is a crucial player in the non-canonical NF-kB pathway and its dysregulation has shown detrimental effects in immune response leading to various inflammatory diseases and cancers. While the ß-strands predicted using the backbone chemical shifts in this study largely conform with the available crystal structure, the helical turns present in the crystal structure are not observed in our results.


Assuntos
Subunidade p52 de NF-kappa B , Ressonância Magnética Nuclear Biomolecular , Domínios Proteicos , Subunidade p52 de NF-kappa B/química , Subunidade p52 de NF-kappa B/metabolismo , Multimerização Proteica , Humanos , Sequência de Aminoácidos
12.
Protein Sci ; 33(11): e5184, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39412374

RESUMO

The NF-κB family consists of the key transcription factors of the NF-κB signaling pathway, well known for its role in innate immune response, organogenesis, and a variety of cellular processes. The five NF-κB subunits-RelA, RelB, c-Rel, p50, and p52-are functional dimers, each of which share a conserved DNA binding domain which contains the dimerization domain (DD) as well. The NF-κB subunits can form 15 potential dimers among themselves of which, RelA-p50 is extensively studied and has largely become synonymous with NF-κB for transcription activation. While various reports have highlighted the importance of NF-κB subunit specificity in the transcription regulation of certain target genes, the dynamic nature of the NF-κB dimer composition is not well understood. In this study, we biophysically characterized six combinatorial dimers from three NF-κB subunits: RelA, p50, and p52, using NMR spectroscopy and differential scanning calorimetry. We show that the dimer composition is dynamic and can readily undergo exchange although at varied rates. Among the six dimers formed, RelA-p52 is found to be the most stable dimer with RelA-RelA being the least. Our results provide a plausible explanation as to why the RelA-p52 heterodimer is active during the later stages of the NF-κB activation and serve as a link between the canonical and non-canonical NF-κB pathway.


Assuntos
Subunidade p52 de NF-kappa B , Multimerização Proteica , Fator de Transcrição RelA , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/química , Fator de Transcrição RelA/genética , Humanos , Subunidade p52 de NF-kappa B/metabolismo , Subunidade p52 de NF-kappa B/química , Subunidade p52 de NF-kappa B/genética , Transdução de Sinais , Ressonância Magnética Nuclear Biomolecular
13.
Res Sq ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39399676

RESUMO

Vaccines targeting the complex pre-erythrocytic stage of Plasmodium parasites may benefit from inclusion of multiple antigens. However, discerning protective effects can be difficult because newer candidates may not be as protective as leading antigens like the circumsporozoite protein (CSP) in the conventional pre-clinical mouse model. We developed a modified mouse model challenge strategy that maximizes the contribution of T cells induced by novel candidate antigens at the sporozoite challenge time point and used this approach to test Plasmodium P36 and P52 vaccine candidates alone and in concert with non-protective doses of CSP. Co-administration of P36 and/or P52 with CSP achieved 80-100% sterile protection in mice, compared to only 7-30% protection for each individual antigen. P36 and P52 vaccination induced murine CD4+ and CD8+ T cell responses, but not antibody responses. This study adds P36 and P52 as promising vaccine antigens that may enhance protection achieved by CSP vaccination.

14.
Adv Healthc Mater ; : e2402314, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171764

RESUMO

The confused gene expressions and molecular mechanisms for mitochondrial dysfunction of traditional nanoenzymes is a challenge for tumor therapy. Herein, a nano-bacilliform-enzyme obtains the ability to inhibit p52-ZER6 signal pathway, regulate the genes related to mitochondrial metabolism, and possess the GOx/CAT/POD-like property. NBE acquires catalytic activity from the electronic energy transition. The tannin of NBE as a mitochondrial (Mito)-targeting guide overloads MitoROS, and then metabolic disorder and lipid peroxidation of Mito membrane occurs, thus leading to a novel death pathway called PAFerroptosis (pyroptosis, apoptosis, and Ferroptosis). Simultaneously, in order to refrain from mitophagy, hydroxychloroquine is mixed with NBE to form a combo with strength pyroptosis. As a result, NBE/combo improves the PAFerroptosis obviously by activation of CD8+T cells and inactivation of MDSC cells, up-regulating expression of caspase-3 signal pathway, intercepting DHODH pathway to arrive excellent antitumor effect (93%). Therefore, this study establishes a rational nanoenzyme for mitochondrial dysfunction without mitophagy for effective antitumor therapy.

15.
J Virol Methods ; 314: 114685, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36709885

RESUMO

BACKGROUND: Maternal acute primary cytomegalovirus (CMV) infection during the first trimester may cause severe long-term sequelae in newborns. For risk assessment, serological screening is routinely performed in pregnant women based on IgM, IgG and avidity tests using whole-virus antigen. A recent study evaluated the diagnostic value of recombinant protein-based ELISAs as second-line tests in pregnancy CMV screening, including anti-p52 IgM and anti-gB IgG as markers defining the early and late phase of infection, respectively. In the present study, these recombinant ELISAs were used as first-line screening tests in daily laboratory routine and compared to lysate-based assays with respect to [i] the number of conclusive results obtained with the initial sample and [ii] the underlying workload. METHODS: 553 unselected routine serum samples from pregnant women were tested for anti-CMV IgM and IgG antibodies using lysate-based ELISAs and avidity testing. Anti-CMV IgM antibodies against recombinant p52 and anti-CMV IgG antibodies against recombinant glycoprotein B (gB) were also determined by ELISA. All assays were performed and interpreted according to the manufacturer's instructions. RESULTS: For lysate-based IgM, IgG and avidity testing, 84.6 % of samples yielded conclusive results in a total of 1156 tests, while 15.4 % needed follow-up testing of a consecutive sample. Anti-p52 CMV IgM and anti-gB CMV IgG testing produced conclusive results for 92.8 % of samples in a total of 1026 tests, while 7.2 % samples required follow-up testing. CONCLUSIONS: The first-line use of ELISAs measuring anti-p52 CMV IgM and anti-gB CMV IgG antibodies to test for maternal CMV infection increases the number of conclusive results derived from an initial serum sample while requiring a considerably lower number of tests compared to the lysate-based approach. For day-to-day routines in a diagnostic laboratory, this high efficiency of the recombinant testing approach has significant practical relevance.


Assuntos
Infecções por Citomegalovirus , Complicações Infecciosas na Gravidez , Gravidez , Feminino , Recém-Nascido , Humanos , Citomegalovirus , Complicações Infecciosas na Gravidez/diagnóstico , Imunoglobulina M , Afinidade de Anticorpos , Infecções por Citomegalovirus/diagnóstico , Anticorpos Antivirais , Testes Sorológicos/métodos , Imunoglobulina G , Proteínas Recombinantes
16.
Cell Biosci ; 12(1): 43, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379326

RESUMO

BACKGROUND: Nuclear factor-κB is a multi-subunit transcription factor that plays a central role in cellular senescence. We previously reported that an increase in the p52 subunit is seen in senescent cells and aged tissue. In the current work, we examined the mechanism by which p52 is activated and whether the increase in p52 promotes senescence. RESULTS: Using both primary mouse embryonic fibroblasts (MEFs) and WI-38 human lung fibroblasts, we examined cells after serial passage and following prolonged culture. An increase in p52 was found in the nucleus relative to pre-senescent cells. The increase in p52 protein was not reflected by an increase in NFKB2 mRNA or by an increase in the abundance of upstream activating kinases, IKKα and NIK. To examine whether p52 promotes senescence, we over-expressed mature p52 in primary MEFs. Significantly more senescence was seen compared to control, a finding not seen with p52 mutated at critical DNA binding residues. In addition, blocking p52 nuclear translocation with the peptide inhibitor, SN52, decreased ß-galactosidase (ß-gal) formation. Subsequent filtration studies demonstrated that proteins in conditioned media (CM) were necessary for the increase in p52 and mass spectrometry identified S100A4 and cyclophilin A (CYPA) as potential factors in CM necessary for induction of p52. The requirement of these proteins in CM for induction of p52 was confirmed using depletion and supplementation studies. In addition, we found that activation of STAT3 signaling was required for the increase in p52. Finally, genome wide ChIP-sequencing analysis confirmed that there is an increase in p52 chromatin enrichment with senescence and identified several downstream factors whose expression is regulated by increased p52 binding. CONCLUSIONS: These results demonstrate that p52 nuclear translocation is increased in senescent cells by factors in conditioned media and that mature p52 induces cellular senescence. The data are consistent with the prior observation that p52 is elevated in aged tissue and support the hypothesis that p52 contributes to organismal aging.

17.
Front Vet Sci ; 9: 931477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909675

RESUMO

Bovine rotavirus A (boRVA) strains are common causative agents of diarrhea in calves, resulting in economic losses to the beef and dairy industry. Importantly, this virus has a zoonotic relevance due to its ability to reassort with human rotaviruses. In this study, fecal samples were collected from three calves with diarrhea during an outbreak on a dairy farm. The genetic material of boRVA was detected by real-time reverse transcription PCR (rtPCR) in two samples. Then the virus in one of these positive samples was identified as a novel boRVA genotype closely related with human rotavirus strains mainly from the USA based on whole-genome characterization. However, we consider the novel boRVA as the etiological agent of the outbreak due to the lesions associated with a rotavirus infection. Further studies are necessary to clarify the evolutionary advantages that novel rotavirus genotypes may have.

18.
J Mol Med (Berl) ; 100(7): 985-995, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672519

RESUMO

Regulatory T cells (Treg cells) act as a major rheostat regulating the strength of immune responses, enabling tolerance of harmless foreign antigens, and preventing the development of pathogenic immune responses in various disease settings such as cancer and autoimmunity. Treg cells are present in all lymphoid and non-lymphoid tissues, and the latter often fulfill important tasks required for the physiology of their host organ. The activation of NF-κB transcription factors is a central pathway for the reprogramming of gene expression in response to inflammatory but also homeostatic cues. Genetic mouse models have revealed essential functions for NF-κB transcription factors in modulating Treg development and function, with some of these mechanistic insights confirmed by recent studies analyzing Treg cells from patients harboring point mutations in the genes encoding NF-κB proteins. Molecular insights into the NF-κB pathway in Treg cells hold substantial promise for novel therapeutic strategies to manipulate dysfunctional or inadequate cell numbers of immunosuppressive Treg cells in autoimmunity or cancer. Here, we provide an overview of the manifold roles that NF-κB factors exert in Treg cells.


Assuntos
NF-kappa B , Linfócitos T Reguladores , Animais , Autoimunidade , Humanos , Tolerância Imunológica , Camundongos , NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo
19.
Brain Res Bull ; 178: 108-119, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838851

RESUMO

INTRODUCTION: The aim of this study was to determine the anti-inflammatory effect of female sex hormones on the level of intracellular molecules of cytokine signaling pathway after diffuse traumatic brain injury (TBI) in ovariectomized rats. METHODS: Female rats were divided into 10 groups: control, sham, TBI, Vehicle (oil), Vehicle E1 (33.3 µg/kg), E2 (1 mg / kg), P1 (1.7 mg/kg), P2 (8 mg / kg), E2 + P1. All drugs were injected 0.5 h after TBI. Brain edema and the brain levels of P-STAT-3, NFκB-P52, NFκB-P65, P-IκB, and SOCS-3 by immunohistochemistry measured at 24 h after TBI. RESULTS: Increased brain edema after TBI was inhibited by different doses of estrogen, progesterone (P < 0.001), and E2 + P1 (P < 0.05). The brain levels of P-STAT-3, NFκB-P52, NFκB-P65, and p-IκBα that increased after TBI was decreased only by E2 (P < 0.05). E2 and E2 + P1 have increased the SOCS-3 level after TBI (P < 0.05). Also, there was a difference between the E2 with E1 and two progesterone doses (P < 0.05). So that in all cases, the effects of E2 were more significant than the other groups. The target cells for these effects of E2 were microglia and astrocytes. CONCLUSION: The results indicate that one of the probable mechanism(s) of estrogen anti-inflammatory effect after TBI is either reduction of p-STAT-3, NFκB-P52, p-NFκB-P65, and p-IκBα or increase in SOCS-3 molecules involved in the signaling pathway of inflammatory cytokines.


Assuntos
Edema Encefálico/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Estrogênios/farmacologia , Doenças Neuroinflamatórias/tratamento farmacológico , Progesterona/farmacologia , Animais , Modelos Animais de Doenças , Estrogênios/administração & dosagem , Feminino , Progesterona/administração & dosagem , Ratos
20.
Braz J Microbiol ; 42(2): 508-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031662

RESUMO

A green house study was conducted to investigate the ability of an isolate of Trichoderma harzianum (P52) and arbuscular mycorrhizal fungi (AMF) in enhancing growth and control of a wilt pathogen caused by Fusarium oxysporum f. sp. lycopersici in tomato seedlings. The plants were grown in plastic pots filled with sterilized soils. There were four treatments applied as follows; P52, AMF, AMF + P52 and a control. A completely randomized design was used and growth measurements and disease assessment taken after 3, 6 and 9 weeks. Treatments that significantly (P < 0.05) enhanced heights and root dry weights were P52, AMF and a treatment with a combination of both P52 and AMF when compared the control. The treatment with both P52 and AMF significantly (P < 0.05) enhanced all growth parameters (heights; shoot and root dry weight) investigated compared to the control. Disease severity was generally lower in tomato plants grown with isolate P52 and AMF fungi either individually or when combined together, though the effect was not statistically significant (P≥ 0.05). A treatment combination of P52 + AMF had less trend of severity as compared to each individual fungus. T. harzianum and AMF can be used to enhance growth in tomato seedlings.

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