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1.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271287

RESUMO

DNA polymerases synthesize DNA from deoxyribonucleotides in a semiconservative manner and serve as the core of DNA replication and repair machinery. In eukaryotic cells, there are 2 genome-containing organelles, mitochondria, and plastids, which were derived from an alphaproteobacterium and a cyanobacterium, respectively. Except for rare cases of genome-lacking mitochondria and plastids, both organelles must be served by nucleus-encoded DNA polymerases that localize and work in them to maintain their genomes. The evolution of organellar DNA polymerases has yet to be fully understood because of 2 unsettled issues. First, the diversity of organellar DNA polymerases has not been elucidated in the full spectrum of eukaryotes. Second, it is unclear when the DNA polymerases that were used originally in the endosymbiotic bacteria giving rise to mitochondria and plastids were discarded, as the organellar DNA polymerases known to date show no phylogenetic affinity to those of the extant alphaproteobacteria or cyanobacteria. In this study, we identified from diverse eukaryotes 134 family A DNA polymerase sequences, which were classified into 10 novel types, and explored their evolutionary origins. The subcellular localizations of selected DNA polymerases were further examined experimentally. The results presented here suggest that the diversity of organellar DNA polymerases has been shaped by multiple transfers of the PolI gene from phylogenetically broad bacteria, and their occurrence in eukaryotes was additionally impacted by secondary plastid endosymbioses. Finally, we propose that the last eukaryotic common ancestor may have possessed 2 mitochondrial DNA polymerases, POP, and a candidate of the direct descendant of the proto-mitochondrial DNA polymerase I, rdxPolA, identified in this study.


Assuntos
Cianobactérias , Organelas , Organelas/genética , Filogenia , DNA Polimerase Dirigida por DNA/genética , Plastídeos/genética , Mitocôndrias , Cianobactérias/genética , Simbiose
2.
Support Care Cancer ; 32(7): 421, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856947

RESUMO

PURPOSE: Determining whether patients' unrealistic expectations of chemotherapy as a cure were associated with their perception of the disclosure of incurability. METHODS: This prospective study included consecutive patients with pretreated non-small cell lung cancer from four study sites. Patients and their oncologists were asked whether they perceived the disclosure of cancer incurability. Patients were also asked if they thought that chemotherapy was curative. We followed up on whether the deceased patients received specialized palliative care 14 months after their last enrollment. Multiple regression analyses were conducted to examine the association between the expectation of chemotherapy as a cure and patient/oncologist-reported perceptions of the disclosure of incurability. RESULTS: We analyzed 200 patients, 77 (38.5%) of whom had unrealistic expectations of a cure. Based on patients' perceptions, incurability was disclosed to 138 (69.0%) patients, and based on their oncologists' perceptions, incurability was disclosed to 185 (92.5%) patients (patient/oncologist agreements, κ = 0.19). Patients without a perception of the oncologist's disclosure of incurability-regardless of their oncologist's perception-were more likely to have unrealistic expectations of a cure than patients for whom both patient and oncologist perceptions were present. Patients who had unrealistic expectations of chemotherapy as a cure were shown to be significantly less likely to have received specialized palliative care, after adjusting for covariates (adjusted OR, 0.45; 95% CI, 0.23-0.91; p = .027). CONCLUSION: Oncologists' disclosure of incurability was not fully recognized by patients, and expectations of chemotherapy as a cure were associated with patients' perception of the disclosure of incurability.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Cuidados Paliativos , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/psicologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Neoplasias Pulmonares/psicologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/terapia , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Cuidados Paliativos/psicologia , Cuidados Paliativos/métodos , Relações Médico-Paciente , Idoso de 80 Anos ou mais , Análise de Regressão , Revelação da Verdade , Adulto , Antineoplásicos/uso terapêutico
3.
BMC Oral Health ; 24(1): 766, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971720

RESUMO

BACKGROUND: Oral health problems have increased among older adults. Oral hypofunction is characterized by seven signs and symptoms: oral uncleanness, oral dryness, decline in occlusal force, decline in the movement function of the tongue and lips, decline in tongue pressure, decline in masticatory function, and decline in swallowing function, the latter being a significant risk factors for oral frailty. Recent research has suggested that salivary biomarkers can be used to assess not only oral diseases, including dental caries and periodontitis, but also systemic diseases, such as cancer and diabetes mellitus. This cross-sectional study investigated the relationship between oral hypofunction and the levels of salivary biomarkers. METHODS: In total, 116 patients, aged 65 years or older, were included in this cross-sectional study. If three or more signs or symptoms in seven kinds of tests met the criteria of each test, oral hypofunction was diagnosed. The levels of biomarkers in the saliva collected from the patients were analyzed using an enzyme-linked immunosorbent assay. RESULTS: In total, 63.8% of patients were diagnosed with oral hypofunction. Multivariable linear regression analysis showed that calprotectin levels in the saliva were significantly related to oral moisture and masticatory function. Furthermore, 8-OHdG levels in saliva were associated with the movement function of the tongue and lips and oral hygiene level, and salivary AGE correlated only with the movement function of the tongue and lips. Multiple logistic regression analysis revealed that calprotectin levels in the saliva were significantly correlated with the prevalence of oral hypofunction, even after adjusting for age, sex, and periodontal status. However, none of the biomarker levels in the saliva had a significant relationship with the number of examinations outside the reference range. CONCLUSIONS: Calprotectin, 8-OHdG, and AGE levels are associated with oral hypofunction in older adults.


Assuntos
Biomarcadores , Saliva , Humanos , Estudos Transversais , Idoso , Saliva/química , Saliva/metabolismo , Feminino , Biomarcadores/análise , Masculino , Idoso de 80 Anos ou mais , Doenças da Boca/metabolismo , Doenças da Boca/fisiopatologia , Xerostomia/metabolismo , Xerostomia/fisiopatologia , Complexo Antígeno L1 Leucocitário/análise
4.
BMC Cancer ; 23(1): 834, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37674153

RESUMO

BACKGROUND: Osteoblastic bone reaction (OBR) refers to an increase in bone density at the site of bone metastasis or the appearance of new sclerotic bone lesions after anticancer treatment. OBR can be misunderstood as disease progression. In this study, we aimed to investigate the prevalence and details of OBR and its association with clinical outcomes in patients with epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) treated with osimertinib. METHODS: This was a single-center, retrospective cohort study. We reviewed patients who were diagnosed with EGFR-mutant NSCLC with bone metastasis and received osimertinib as a first-line treatment between February 2018 and October 2022. The OBR was evaluated by comparing baseline computed tomography (CT) scans with the first CT scan after treatment initiation. RESULTS: A total of 45 patients were included in this study. Thirty-seven patients (82%) developed OBR. OBR developed in 94% (n = 16) of patients with sclerotic bone lesions (n = 17) at baseline. Similarly, OBR developed in lytic and mixed bone lesions in 76% and 82% of patients with lytic and mixed lesions, respectively. Progression-free survival (PFS) did not differ significantly between patients with (OBR group) and without OBR (non-OBR group) (median PFS, 24 months vs. 17 months; hazard ratio (HR), 0.62; 95% CI, 0.24-1.6; p = 0.31). In univariate analysis, the OBR group showed a trend toward longer skeletal-related events-free survival (SRE-FS) than the non-OBR group (median SRE-FS, 26 months vs. 12 months; HR, 0.53; 95% CI, 0.21-1.33; p = 0.16). Multivariate analysis showed OBR was a significant independent predictor of SRE-FS (HR, 0.35; 95% CI, 0.13-0.92; p = 0.034). CONCLUSIONS: OBR developed in most patients with NSCLC and bone metastasis who received osimertinib treatment. The increased incidence of OBR in patients with EGFR-mutant NSCLC with bone metastasis treated with osimertinib should not be confused with disease progression, and treatment decisions should be made carefully.


Assuntos
Doenças Ósseas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos Retrospectivos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Progressão da Doença , Receptores ErbB/genética , Mutação
5.
J Periodontal Res ; 58(2): 262-273, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36579753

RESUMO

BACKGROUND AND OBJECTIVE: Lipocalin 2 (LCN2), a glycoprotein expressed in epithelial cells and leukocytes, has an antibacterial effect and plays a role in innate immunity. The delivery of LCN2 encapsulated in liposomes to oral epithelium may be useful to prevent oral infectious diseases. This study aimed to investigate the inhibitory effect of LCN2, artificially synthesized using a cell-free protein synthesis (CFPS) system, on the adhesion of Porphyromonas gingivalis to oral epithelial cells in order to approach oral healthcare using LCN2. METHODS: LCN 2 was synthesized using a CFPS system and assayed by Western blotting, mass spectrometry and enzyme-linked immunosorbent assay (ELISA). The bilayer liposomes were prepared by the spontaneous transfer method using 1,2-dioleoyl-sn-glycero-3 phosphocholine (DOPC), 3-sn-phosphatidylcholine from Egg Yolk (Egg-PC), and 1,2-dioleoyl-sn-glycero-3 phosphoethanolamine (DOPE). The cellular and medium fractions derived from the culture of oral epithelial cells with liposome-encapsulated LCN2 were assayed by Western blotting and ELISA. The effect of the synthesized LCN2 on adhesion of the labeled P. gingivalis to oral epithelial cells was investigated as an evaluation of its antibacterial activity. RESULTS: The synthesized LCN2 protein was identified by Western blotting; its amino acid sequence was similar to that of recombinant LCN2 protein. The additions of DOPE and octa-arginine in the outer lipid-layer components of liposome significantly increased the delivery of liposomes to epithelial cells. When oral epithelial cells were cultured with the synthesized and liposome-encapsulated LCN2, LCN2 was identified in the cellular and medium fractions by Western blotting and its concentration in the cellular fraction from the culture with the synthesized LCN2 was significantly higher than that of a template DNA-free protein. The synthesized LCN2 and liposome-encapsulated LCN2 significantly inhibited the adhesion of P. gingivalis to oral epithelial cells compared with template DNA-free protein. CONCLUSION: LCN2 was artificially synthesized by a CFPS system, encapsulated in liposomes, and delivered to oral epithelial cells, and demonstrated an antibacterial action against P. gingivalis. This approach may become a useful model for oral healthcare.


Assuntos
Lipossomos , Porphyromonas gingivalis , Humanos , Lipossomos/química , Lipocalina-2/farmacologia , Células Epiteliais
6.
Proc Natl Acad Sci U S A ; 117(10): 5364-5375, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32094181

RESUMO

Nucleomorphs are relic endosymbiont nuclei so far found only in two algal groups, cryptophytes and chlorarachniophytes, which have been studied to model the evolutionary process of integrating an endosymbiont alga into a host-governed plastid (organellogenesis). However, past studies suggest that DNA transfer from the endosymbiont to host nuclei had already ceased in both cryptophytes and chlorarachniophytes, implying that the organellogenesis at the genetic level has been completed in the two systems. Moreover, we have yet to pinpoint the closest free-living relative of the endosymbiotic alga engulfed by the ancestral chlorarachniophyte or cryptophyte, making it difficult to infer how organellogenesis altered the endosymbiont genome. To counter the above issues, we need novel nucleomorph-bearing algae, in which endosymbiont-to-host DNA transfer is on-going and for which endosymbiont/plastid origins can be inferred at a fine taxonomic scale. Here, we report two previously undescribed dinoflagellates, strains MGD and TGD, with green algal endosymbionts enclosing plastids as well as relic nuclei (nucleomorphs). We provide evidence for the presence of DNA in the two nucleomorphs and the transfer of endosymbiont genes to the host (dinoflagellate) genomes. Furthermore, DNA transfer between the host and endosymbiont nuclei was found to be in progress in both the MGD and TGD systems. Phylogenetic analyses successfully resolved the origins of the endosymbionts at the genus level. With the combined evidence, we conclude that the host-endosymbiont integration in MGD/TGD is less advanced than that in cryptophytes/chrorarachniophytes, and propose the two dinoflagellates as models for elucidating organellogenesis.


Assuntos
Cercozoários/ultraestrutura , Criptófitas/ultraestrutura , Dinoflagellida/ultraestrutura , Evolução Molecular , Genomas de Plastídeos , Plastídeos/fisiologia , Simbiose , Núcleo Celular/genética , Núcleo Celular/fisiologia , Cercozoários/classificação , Cercozoários/genética , Clorófitas/classificação , Clorófitas/fisiologia , Clorófitas/ultraestrutura , Criptófitas/classificação , Criptófitas/genética , Dinoflagellida/classificação , Dinoflagellida/genética , Modelos Biológicos , Filogenia , Plastídeos/genética
7.
Proc Natl Acad Sci U S A ; 116(32): 15973-15978, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31235587

RESUMO

Cyanobacteria are one of the most important contributors to oceanic primary production and survive in a wide range of marine habitats. Much effort has been made to understand their ecological features, diversity, and evolution, based mainly on data from free-living cyanobacterial species. In addition, symbiosis has emerged as an important lifestyle of oceanic microbes and increasing knowledge of cyanobacteria in symbiotic relationships with unicellular eukaryotes suggests their significance in understanding the global oceanic ecosystem. However, detailed characteristics of these cyanobacteria remain poorly described. To gain better insight into marine cyanobacteria in symbiosis, we sequenced the genome of cyanobacteria collected from a cell of a pelagic dinoflagellate that is known to host cyanobacterial symbionts within a specialized chamber. Phylogenetic analyses using the genome sequence revealed that the cyanobacterium represents an underdescribed lineage within an extensively studied, ecologically important group of marine cyanobacteria. Metagenomic analyses demonstrated that this cyanobacterial lineage is globally distributed and strictly coexists with its host dinoflagellates, suggesting that the intimate symbiotic association allowed the cyanobacteria to escape from previous metagenomic studies. Furthermore, a comparative analysis of the protein repertoire with related species indicated that the lineage has independently undergone reductive genome evolution to a similar extent as Prochlorococcus, which has the most reduced genomes among free-living cyanobacteria. Discovery of this cyanobacterial lineage, hidden by its symbiotic lifestyle, provides crucial insights into the diversity, ecology, and evolution of marine cyanobacteria and suggests the existence of other undiscovered cryptic cyanobacterial lineages.


Assuntos
Cianobactérias/genética , Dinoflagellida/microbiologia , Genômica/métodos , Geografia , Filogenia , Análise de Célula Única/métodos , Sequência de Bases , Cianobactérias/isolamento & purificação , Código de Barras de DNA Taxonômico , Genoma Bacteriano , Funções Verossimilhança , Metagenômica , Simbiose/genética
8.
Proc Biol Sci ; 287(1934): 20201538, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32873198

RESUMO

We here report the phylogenetic position of barthelonids, small anaerobic flagellates previously examined using light microscopy alone. Barthelona spp. were isolated from geographically distinct regions and we established five laboratory strains. Transcriptomic data generated from one Barthelona strain (PAP020) were used for large-scale, multi-gene phylogenetic (phylogenomic) analyses. Our analyses robustly placed strain PAP020 at the base of the Fornicata clade, indicating that barthelonids represent a deep-branching metamonad clade. Considering the anaerobic/microaerophilic nature of barthelonids and preliminary electron microscopy observations on strain PAP020, we suspected that barthelonids possess functionally and structurally reduced mitochondria (i.e. mitochondrion-related organelles or MROs). The metabolic pathways localized in the MRO of strain PAP020 were predicted based on its transcriptomic data and compared with those in the MROs of fornicates. We here propose that strain PAP020 is incapable of generating ATP in the MRO, as no mitochondrial/MRO enzymes involved in substrate-level phosphorylation were detected. Instead, we detected a putative cytosolic ATP-generating enzyme (acetyl-CoA synthetase), suggesting that strain PAP020 depends on ATP generated in the cytosol. We propose two separate losses of substrate-level phosphorylation from the MRO in the clade containing barthelonids and (other) fornicates.


Assuntos
Evolução Biológica , Eucariotos/fisiologia , Filogenia , Anaerobiose , Eucariotos/metabolismo , Mitocôndrias/metabolismo , Organelas/metabolismo
9.
J Periodontal Res ; 55(4): 539-550, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170733

RESUMO

BACKGROUND AND OBJECTIVES: Diabetes mellitus (DM), a risk factor of periodontal diseases, exacerbates the pathological condition of periodontitis. A major factor for DM complications is advanced glycation end-products (AGEs) that accumulate in periodontal tissues and cause inflammatory events. Lipocalin 2 (LCN2) is an antimicrobial peptide and inflammation-related factor, and LCN2 levels increase in DM. In this study, the effects of AGEs and lipopolysaccharide of Porphyromonas gingivalis (P g-LPS) on LCN2 expression in human oral epithelial cells (TR146 cells) and the role of secreted LCN2 in periodontitis with DM were investigated. MATERIAL AND METHODS: TR146 cells were cultured with AGEs (AGE2) and control BSA and cell viability was estimated, or with P g-LPS. Conditioned medium and cell lysates were prepared from cultures of epithelial cells and used for Western blotting and ELISA to analyze LCN2, RAGE, IL-6, MAPK, and NF-κB. RNA was isolated from AGE-treated TR146 cells and differentiated HL-60 (D-HL-60) cells and used for quantitative real-time PCR to examine the expression of LCN2 and interleukin-6 (IL-6) mRNAs. RAGE- and LCN2-siRNAs (siRAGE, siLCN2) were transfected into epithelial cells, and AGE-induced LCN2 expression was investigated. D-HL-60 cells were co-cultured with TR146 cells that were transfected with siLCN2 and treated with AGEs, and IL-6 mRNA expression in D-HL-60 cells and cell migration was investigated. RESULTS: AGEs increased the expression levels of LCN2 and IL-6 in oral epithelial cells. siRAGE and a neutralizing antibody for RAGE inhibited AGE-induced LCN2 expression. AGEs stimulated the phosphorylation of ERK, p38, and NF-κB in epithelial cells, and their inhibitors suppressed AGE-induced LCN2 expression. In contrast, P g-LPS did not show a significant increase in LCN2 level in TR146 cells that expressed Toll-like receptor 2. In co-culture experiments, AGE-induced LCN2 inhibited IL-6 mRNA expression in D-HL-60 cells, and LCN2 knockdown in epithelial cells suppressed HL-60 cell migration. CONCLUSION: These results suggested that AGEs increase LCN2 expression via RAGE, MAPK, and NF-κB signaling pathways in oral epithelial cells, and secreted LCN2 may influence the pathological condition of periodontitis with DM.


Assuntos
Produtos Finais de Glicação Avançada , Lipocalina-2 , Porphyromonas gingivalis , Células Cultivadas , Células Epiteliais/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Lipocalina-2/genética , Lipocalina-2/metabolismo , NF-kappa B/metabolismo , Porphyromonas gingivalis/metabolismo , Receptor para Produtos Finais de Glicação Avançada/genética
10.
Molecules ; 24(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31619000

RESUMO

Advanced glycation end-products (AGEs) cause diabetes mellitus (DM) complications and accumulate more highly in periodontal tissues of patients with periodontitis and DM. AGEs aggravate periodontitis with DM by increasing the expression of inflammation-related factors in periodontal tissues. 6-Shogaol, a major compound in ginger, has anti-inflammatory and anti-oxidative activities. However, the influence of shogaol on DM-associated periodontitis is not well known. In this study, the effects of 6-shogaol on AGEs-induced oxidative and anti-oxidative responses, and IL-6 and ICAM-1 expression in human gingival fibroblasts (HGFs) were investigated. When HGFs were cultured with 6-shogaol and AGEs, the activities of reactive oxygen species (ROS) and antioxidant enzymes (heme oxygenase-1 [HO-1] and NAD(P)H quinone dehydrogenase 1 [NQO1]), and IL-6 and ICAM-1 expressions were investigated. RAGE expression and phosphorylation of MAPKs and NF-κB were examined by western blotting. 6-Shogaol significantly inhibited AGEs-induced ROS activity, and increased HO-1 and NQO1 levels compared with the AGEs-treated cells. The AGEs-stimulated expression levels of receptor of AGE (RAGE), IL-6 and ICAM-1 and the phosphorylation of p38, ERK and p65 were attenuated by 6-shogaol. These results suggested that 6-shogaol inhibits AGEs-induced inflammatory responses by regulating oxidative and anti-oxidative activities and may have protective effects on periodontitis with DM.


Assuntos
Catecóis/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Produtos Finais de Glicação Avançada/genética , Molécula 1 de Adesão Intercelular/genética , Interleucina-6/genética , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Gengiva/citologia , Produtos Finais de Glicação Avançada/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Mol Biol Evol ; 34(9): 2355-2366, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28549159

RESUMO

Nonphotosynthetic plastids retain important biological functions and are indispensable for cell viability. However, the detailed processes underlying the loss of plastidal functions other than photosynthesis remain to be fully understood. In this study, we used transcriptomics, subcellular localization, and phylogenetic analyses to characterize the biochemical complexity of the nonphotosynthetic plastids of the apochlorotic diatom Nitzschia sp. NIES-3581. We found that these plastids have lost isopentenyl pyrophosphate biosynthesis and ribulose-1,5-bisphosphate carboxylase/oxygenase-based carbon fixation but have retained various proteins for other metabolic pathways, including amino acid biosynthesis, and a portion of the Calvin-Benson cycle comprised only of glycolysis/gluconeogenesis and the reductive pentose phosphate pathway (rPPP). While most genes for plastid proteins involved in these reactions appear to be phylogenetically related to plastid-targeted proteins found in photosynthetic relatives, we also identified a gene that most likely originated from a cytosolic protein gene. Based on organellar metabolic reconstructions of Nitzschia sp. NIES-3581 and the presence/absence of plastid sugar phosphate transporters, we propose that plastid proteins for glycolysis, gluconeogenesis, and rPPP are retained even after the loss of photosynthesis because they feed indispensable substrates to the amino acid biosynthesis pathways of the plastid. Given the correlated retention of the enzymes for plastid glycolysis, gluconeogenesis, and rPPP and those for plastid amino acid biosynthesis pathways in distantly related nonphotosynthetic plastids and cyanobacteria, we suggest that this substrate-level link with plastid amino acid biosynthesis is a key constraint against loss of the plastid glycolysis/gluconeogenesis and rPPP proteins in multiple independent lineages of nonphotosynthetic algae/plants.


Assuntos
Diatomáceas/metabolismo , Plastídeos/genética , Plastídeos/metabolismo , Aminoácidos/biossíntese , Evolução Biológica , Citosol/metabolismo , Evolução Molecular , Perfilação da Expressão Gênica/métodos , Fotossíntese/genética , Filogenia , Plantas/genética
12.
J Eukaryot Microbiol ; 65(5): 669-678, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29478272

RESUMO

The ancestral kareniacean dinoflagellate has undergone tertiary endosymbiosis, in which the original plastid is replaced by a haptophyte endosymbiont. During this plastid replacement, the endosymbiont genes were most likely flowed into the host dinoflagellate genome (endosymbiotic gene transfer or EGT). Such EGT may have generated the redundancy of functionally homologous genes in the host genome-one has resided in the host genome prior to the haptophyte endosymbiosis, while the other transferred from the endosymbiont genome. However, it remains to be well understood how evolutionarily distinct but functionally homologous genes were dealt in the dinoflagellate genomes bearing haptophyte-derived plastids. To model the gene evolution after EGT in plastid replacement, we here compared the characteristics of the two evolutionally distinct genes encoding plastid-type glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in Karenia brevis and K. mikimotoi bearing haptophyte-derived tertiary plastids: "gapC1h" acquired from the haptophyte endosymbiont and "gapC1p" inherited from the ancestral dinoflagellate. Our experiments consistently and clearly demonstrated that, in the two species examined, the principal plastid-type GAPDH is encoded by gapC1h rather than gapC1p. We here propose an evolutionary scheme resolving the EGT-derived redundancy of genes involved in plastid function and maintenance in the nuclear genomes of dinoflagellates that have undergone plastid replacements. Although K. brevis and K. mikimotoi are closely related to each other, the statuses of the two evolutionarily distinct gapC1 genes in the two Karenia species correspond to different steps in the proposed scheme.


Assuntos
Dinoflagellida/genética , Evolução Molecular , Gliceraldeído-3-Fosfato Desidrogenases/genética , Plastídeos/enzimologia , Proteínas de Protozoários/genética , Dinoflagellida/classificação , Dinoflagellida/enzimologia , Transferência Genética Horizontal , Filogenia , Plastídeos/genética
13.
Proc Natl Acad Sci U S A ; 111(31): 11407-12, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25049384

RESUMO

The evolution of mitochondria and plastids from bacterial endosymbionts were key events in the origin and diversification of eukaryotic cells. Although the ancient nature of these organelles makes it difficult to understand the earliest events that led to their establishment, the study of eukaryotic cells with recently evolved obligate endosymbiotic bacteria has the potential to provide important insight into the transformation of endosymbionts into organelles. Diatoms belonging to the family Rhopalodiaceae and their endosymbionts of cyanobacterial origin (i.e., "spheroid bodies") are emerging as a useful model system in this regard. The spheroid bodies, which appear to enable rhopalodiacean diatoms to use gaseous nitrogen, became established after the divergence of extant diatom families. Here we report what is, to our knowledge, the first complete genome sequence of a spheroid body, that of the rhopalodiacean diatom Epithemia turgida. The E. turgida spheroid body (EtSB) genome was found to possess a gene set for nitrogen fixation, as anticipated, but is reduced in size and gene repertoire compared with the genomes of their closest known free-living relatives. The presence of numerous pseudogenes in the EtSB genome suggests that genome reduction is ongoing. Most strikingly, our genomic data convincingly show that the EtSB has lost photosynthetic ability and is metabolically dependent on its host cell, unprecedented characteristics among cyanobacteria, and cyanobacterial symbionts. The diatom-spheroid body endosymbiosis is thus a unique system for investigating the processes underlying the integration of a bacterial endosymbiont into eukaryotic cells.


Assuntos
Adaptação Fisiológica , Cianobactérias/genética , Diatomáceas/microbiologia , Genoma Bacteriano/genética , Espaço Intracelular/microbiologia , Fotossíntese/genética , Cromossomos Bacterianos/genética , Transporte de Elétrons , Tamanho do Genoma , Dados de Sequência Molecular , Fixação de Nitrogênio/genética , Organelas/metabolismo , Simbiose/genética , Tilacoides/metabolismo
14.
Mol Biol Evol ; 32(10): 2598-604, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26048548

RESUMO

Organisms with nonphotosynthetic plastids often retain genomes; their gene contents provide clues as to the functions of these organelles. Yet the functional roles of some retained genes-such as those coding for ATP synthase-remain mysterious. In this study, we report the complete plastid genome and transcriptome data of a nonphotosynthetic diatom and propose that its ATP synthase genes may function in ATP hydrolysis to maintain a proton gradient between thylakoids and stroma, required by the twin arginine translocator (Tat) system for translocation of particular proteins into thylakoids. Given the correlated retention of ATP synthase genes and genes for the Tat system in distantly related nonphotosynthetic plastids, we suggest that this Tat-related role for ATP synthase was a key constraint during parallel loss of photosynthesis in multiple independent lineages of algae/plants.


Assuntos
ATPases de Cloroplastos Translocadoras de Prótons/metabolismo , Diatomáceas/genética , Genomas de Plastídeos , Fotossíntese , Sistema de Translocação de Argininas Geminadas/metabolismo , Modelos Biológicos , Filogenia , Mapeamento Físico do Cromossomo
15.
Odontology ; 104(2): 152-62, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25649126

RESUMO

Oral epithelial cells produce antimicrobial peptides (AMPs) to prevent microbial infection. Calprotectin (S100A8/S100A9) is one of these AMPs in oral epithelial cells, the expression of which is up-regulated by interleukin-1α (IL-1α). Hangeshashinto (HST) is a traditional Japanese herbal medicine that has anti-inflammatory effects. The purpose of this study was to investigate the effect of HST on the expression of calprotectin through the regulation of IL-1α in oral epithelial cells. Human oral epithelial cells (TR146) were cultured with HST in the presence or absence of anti-IL-1α antibody or IL-1 receptor antagonist, or with six major components of HST (3,4-dihydroxybenzaldehyde, baicalin, ginsenoside Rb1, glycyrrhizin, oleanolic acid and berberine). The expression of S100A8, S100A9, other AMPs and cytokine mRNAs was examined by RT-PCR and quantitative real-time PCR. Calprotectin expression and IL-1α secretion were investigated by ELISA. HST (6 µg/ml) increased the expression of S100A8/S100A9 mRNAs and calprotectin protein, and also up-regulated ß-defensin 2 (DEFB4) and S100A7 expression. The expression of IL-1α mRNA and its protein was slightly but significantly increased by HST. A neutralizing antibody against IL-1α and IL-1 receptor antagonist inhibited HST-up-regulated S100A8/S100A9 mRNA expression. Although 3,4-dihydroxybenzaldehyde, baicalin and ginsenoside Rb1 as HST components increased S100A8/S100A9 expression, oleanolic acid and berberine decreased their expression. These results suggest that HST increases the expression of calprotectin, DEFB4 and S100A7 in oral epithelial cells. In response to HST, up-regulation of calprotectin expression may be partially induced via IL-1α.


Assuntos
Células Epiteliais/efeitos dos fármacos , Complexo Antígeno L1 Leucocitário/metabolismo , Preparações de Plantas/farmacologia , Células Cultivadas , Células Epiteliais/metabolismo , Humanos , Interleucina-1alfa/metabolismo , Medicina Tradicional do Leste Asiático
16.
J Eukaryot Microbiol ; 62(4): 532-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25594562

RESUMO

Although environmental DNA surveys improve our understanding of biodiversity, interpretation of unidentified lineages is limited by the absence of associated morphological traits and living cultures. Unidentified lineages of marine stramenopiles are called "MAST clades". Twenty-five MAST clades have been recognized: MAST-1 through MAST-25; seven of these have been subsequently discarded because the sequences representing those clades were found to either (1) be chimeric or (2) affiliate within previously described taxonomic groups. Eighteen MAST clades remain without a cellular identity. Moreover, the discarded "MAST-13" has been used in different studies to refer to two different environmental sequence clades. After establishing four cultures representing two different species of heterotrophic stramenopiles and then characterizing their morphology and molecular phylogenetic positions, we determined that the two different species represented the two different MAST-13 clades: (1) a lorica-bearing Bicosoeca kenaiensis and (2) a microaerophilic flagellate previously named "Cafeteria marsupialis". Both species were previously described with only light microscopy; no cultures, ultrastructural data or DNA sequences were available from these species prior to this study. The molecular phylogenetic position of three different "C. marsupialis" isolates was not closely related to the type species of Cafeteria; therefore, we established a new genus for these isolates, Cantina gen. nov.


Assuntos
Estramenópilas/classificação , Estramenópilas/genética , Animais , DNA Ribossômico/genética , Flagelos/ultraestrutura , Processos Heterotróficos , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Água do Mar , Análise de Sequência de DNA , Estramenópilas/citologia , Estramenópilas/isolamento & purificação
18.
Odontology ; 103(1): 66-74, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24276427

RESUMO

Periodontitis is a multifactorial disease associated with genetic and environmental factors. Single-nucleotide polymorphisms (SNPs) are associated with susceptibility to common diseases such as diabetes and periodontitis. Although the oral cavity is exposed to various organisms, the conditions are well controlled by innate and acquired immune systems. Antimicrobial peptides (AMPs) play an important role in the innate immune system; however, the association of AMP-SNPs with periodontitis has not been fully elucidated. This study investigated the relationship between AMP-SNPs and periodontitis in Japanese. One hundred and five Japanese subjects were recruited, which included patients with aggressive, severe, moderate and mild periodontitis, and age-matched healthy controls. Genomic DNA was isolated from peripheral blood and genotypes of SNPs of ß-defensin-1 and lactoferrin genes (DEFB1: rs1799946, rs1800972 and rs11362; and LTF: rs1126478) were investigated using the PCR-Invader assay. Protein level of AMPs in gingival crevicular fluid (GCF) was quantified by ELISA. Case-control studies revealed that the -44 CC genotype of DEFB1 (rs1800972) was associated with periodontitis (OR 2.51), particularly with severe chronic periodontitis (OR 4.15) and with combined severe and moderate chronic periodontitis (OR 4.04). No statistical differences were found in other genotypes. The ß-defensin-1 concentrations in GCF were significantly lower in subjects with the -44 CC genotype of DEFB1 than in those without this genotype. No significant differences between GCF concentrations of AMPs and other genotypes were detected. The -44 CC genotype of the ß-defensin-1 gene (DEFB1 rs1800972) may be associated with susceptibility to chronic periodontitis in Japanese.


Assuntos
Predisposição Genética para Doença , Periodontite/genética , Polimorfismo de Nucleotídeo Único , beta-Defensinas/genética , Adulto , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Humanos , Japão , Masculino , Reação em Cadeia da Polimerase
19.
Anticancer Drugs ; 25(9): 1028-34, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24892721

RESUMO

Resveratrol is a natural polyphenol found in a wide variety of plants, including grapes, berries, and peanuts. Resveratrol can modulate a wide spectrum of molecular targets, including those involved in cancer signaling pathways. Here, we evaluated the role of resveratrol in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and examined the molecular mechanisms in the human hepatocellular carcinoma cell line HepG2. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to assess cell viability, flow cytometry to analyze cell cycle and apoptosis, and immunoblotting to detect protein expression. Resveratrol decreased cell viability at a concentration of 100 µmol/l or higher. At a concentration of 50 µmol/l, resveratrol induced S phase arrest of the cell cycle without apoptosis. In addition, phospho-AMPK increased significantly in a dose-dependent manner. Resveratrol was found to synergistically augment TRAIL-induced apoptosis. The rates of early apoptosis were 3.4, 9.6, and 49.6% on treatment with 50 µmol/l resveratrol, 10 ng/ml TRAIL, and both reagents, respectively. Resveratrol significantly downregulated the expression of survivin in a dose-dependent manner. In conclusion, we found that that resveratrol could augment TRAIL sensitivity by downregulating survivin. These results suggest that combination resveratrol with TRAIL may be an effective new strategy for the treatment of hepatocellular carcinoma.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Estilbenos/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Células Hep G2 , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Fosforilação , Resveratrol , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Survivina
20.
Inorg Chem ; 53(11): 5447-57, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24816331

RESUMO

The 1:2 mixtures of Co(p-tolsal)2, p-tolsal = N-p-tolylsalicylideniminato, and diazo-pyridine ligands, DXpy; X = 1, 2, 3l, 3b, and 4, in MTHF solutions were irradiated at cryogenic temperature to form the corresponding 1:2 cobalt-carbene complexes Co(p-tolsal)2(CXpy)2, with Stotal = 5/2, 9/2, 13/2, 13/2, and 17/2, respectively. The resulting Co(p-tolsal)2(CXpy)2, X = 1, 2, 3l, 3b, and 4, showed magnetic behaviors characteristic of heterospin single-molecule magnets with effective activation barriers, Ueff/kB, of 40, 65, 73, 72, and 74 K, for reorientation of the magnetic moment and temperature-dependent hysteresis loops with a coercive force, Hc, of ∼0, 6.2, 10, 6.5, and 9.0 kOe at 1.9 K, respectively. The relaxation times, τQ, due to a quantum tunneling of magnetization (QTM) were estimated to be 1.6 s for Co(p-tolsal)2(C1py)2, ∼2.0 × 10(3) s for Co(p-tolsal)2(C2py)2, and >10(5) s for Co(p-tolsal)2(CXpy)2; X = 3b, 3l, and 4. In heterospin complexes, organic spins, carbenes interacted with the cobalt ion to suppress the QTM pathway, and the τQ value increased with increasing the Stotal values.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Piridinas/química , Bases de Schiff/química , Ligantes , Metano/análogos & derivados , Metano/química , Estrutura Molecular
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