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1.
Nature ; 584(7821): 403-409, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760000

RESUMO

The tuatara (Sphenodon punctatus)-the only living member of the reptilian order Rhynchocephalia (Sphenodontia), once widespread across Gondwana1,2-is an iconic species that is endemic to New Zealand2,3. A key link to the now-extinct stem reptiles (from which dinosaurs, modern reptiles, birds and mammals evolved), the tuatara provides key insights into the ancestral amniotes2,4. Here we analyse the genome of the tuatara, which-at approximately 5 Gb-is among the largest of the vertebrate genomes yet assembled. Our analyses of this genome, along with comparisons with other vertebrate genomes, reinforce the uniqueness of the tuatara. Phylogenetic analyses indicate that the tuatara lineage diverged from that of snakes and lizards around 250 million years ago. This lineage also shows moderate rates of molecular evolution, with instances of punctuated evolution. Our genome sequence analysis identifies expansions of proteins, non-protein-coding RNA families and repeat elements, the latter of which show an amalgam of reptilian and mammalian features. The sequencing of the tuatara genome provides a valuable resource for deep comparative analyses of tetrapods, as well as for tuatara biology and conservation. Our study also provides important insights into both the technical challenges and the cultural obligations that are associated with genome sequencing.


Assuntos
Evolução Molecular , Genoma/genética , Filogenia , Répteis/genética , Animais , Conservação dos Recursos Naturais/tendências , Feminino , Genética Populacional , Lagartos/genética , Masculino , Anotação de Sequência Molecular , Nova Zelândia , Caracteres Sexuais , Serpentes/genética , Sintenia
3.
Biochem Biophys Res Commun ; 566: 1-8, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34111666

RESUMO

Receptor for advanced glycation end-products (RAGE) and Toll-like receptors (TLRs) are potential therapeutic targets in the treatment of acute and chronic inflammatory diseases. We previously reported that trimebutine, a spasmolytic drug, suppresses RAGE pro-inflammatory signaling pathway in macrophages. The aim of this study was to convert trimebutine to a new small molecule using in silico 3D pharmacophore similarity search, and dissect the mechanistic anti-inflammatory basis. Of note, a unique 3-styrylchromone (3SC), 7-methoxy-3-trimethoxy-SC (7M3TMSC), converted from trimebutine 3D pharmacophore potently suppressed both high mobility group box 1-RAGE and lipopolysaccharide-TLR4 signaling pathways in macrophage-like RAW264.7 cells. More importantly, 7M3TMSC inhibited the phosphorylation of extracellular signaling-regulated kinase 1 and 2 (ERK1/2) and downregulated the production of cytokines, such as interleukin-6. Furthermore, 3D pharmacophore-activity relationship analyses revealed that the hydrogen bond acceptors of the trimethoxy groups in a 3-styryl moiety and the 7-methoxy-group in a chromone moiety in this compound are significant in the dual anti-inflammatory activity. Thus, 7M3TMSC may provide an important scaffold for the development of a new type of anti-inflammatory dual effective drugs targeting RAGE/TLR4-ERK1/2 signaling.


Assuntos
Anti-Inflamatórios/farmacologia , Cromonas/farmacologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor 4 Toll-Like/metabolismo , Trimebutina/farmacologia , Animais , Anti-Inflamatórios/química , Cromonas/química , Proteína HMGB1/metabolismo , Humanos , Camundongos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Trimebutina/química
4.
Mol Ecol ; 30(4): 973-986, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33305388

RESUMO

Very few animals habitually manufacture and use tools. It has been suggested that advanced tool behaviour co-evolves with a suite of behavioural, morphological and life history traits. In fact, there are indications for such an adaptive complex in tool-using crows (genus Corvus species). Here, we sequenced the genomes of two habitually tool-using and ten non-tool-using crow species to search for genomic signatures associated with a tool-using lifestyle. Using comparative genomic and population genetic approaches, we screened for signals of selection in protein-coding genes in the tool-using New Caledonian and Hawaiian crows. While we detected signals of recent selection in New Caledonian crows near genes associated with bill morphology, our data indicate that genetic changes in these two lineages are surprisingly subtle, with little evidence at present for convergence. We explore the biological explanations for these findings, such as the relative roles of gene regulation and protein-coding changes, as well as the possibility that statistical power to detect selection in recently diverged lineages may have been insufficient. Our study contributes to a growing body of literature aiming to decipher the genetic basis of recently evolved complex behaviour.


Assuntos
Corvos , Características de História de Vida , Comportamento de Utilização de Ferramentas , Animais , Corvos/genética , Havaí
5.
Arch Biochem Biophys ; 711: 109029, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34517011

RESUMO

Because of the critical roles of Toll-like receptors (TLRs) and receptor for advanced glycation end-products (RAGE) in the pathophysiology of various acute and chronic inflammatory diseases, continuous efforts have been made to discover novel therapeutic inhibitors of TLRs and RAGE to treat inflammatory disorders. A recent study by our group has demonstrated that trimebutine, a spasmolytic drug, suppresses the high mobility group box 1‒RAGE signaling that is associated with triggering proinflammatory signaling pathways in macrophages. Our present work showed that trimebutine suppresses interleukin-6 (IL-6) production in lipopolysaccharide (LPS, a stimulant of TLR4)-stimulated macrophages of RAGE-knockout mice. In addition, trimebutine suppresses the LPS-induced production of various proinflammatory cytokines and chemokines in mouse macrophage-like RAW264.7 cells. Importantly, trimebutine suppresses IL-6 production induced by TLR2-and TLR7/8/9 stimulants. Furthermore, trimebutine greatly reduces mortality in a mouse model of LPS-induced sepsis. Studies exploring the action mechanism of trimebutine revealed that it inhibits the LPS-induced activation of IL-1 receptor-associated kinase 1 (IRAK1), and the subsequent activations of extracellular signal-related kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and nuclear factor-κB (NF-κB). These findings suggest that trimebutine exerts anti-inflammatory effects on TLR signaling by downregulating IRAK1‒ERK1/2‒JNK pathway and NF-κB activity, thereby indicating the therapeutic potential of trimebutine in inflammatory diseases. Therefore, trimebutine can be a novel anti-inflammatory drug-repositioning candidate and may provide an important scaffold for designing more effective dual anti-inflammatory drugs that target TLR/RAGE signaling.


Assuntos
Anti-Inflamatórios/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Receptores Toll-Like/metabolismo , Trimebutina/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Quimiocinas/metabolismo , Feminino , Interleucina-6/metabolismo , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células RAW 264.7 , Receptor para Produtos Finais de Glicação Avançada/deficiência , Receptor para Produtos Finais de Glicação Avançada/genética , Sepse/induzido quimicamente , Sepse/tratamento farmacológico , Trimebutina/uso terapêutico
6.
Biochem Biophys Res Commun ; 533(4): 1155-1161, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33041002

RESUMO

We previously identified papaverine as an inhibitor of receptor for advanced glycation end-products (RAGE) and showed its suppressive effect on high mobility group box 1 (HMGB1)-mediated responses to inflammation. Here, we found trimebutine to be a 3D pharmacophore mimetics of papaverine. Trimebutine was revealed to have more potent suppressive effects on HMGB1-induced production of pro-inflammatory cytokines, such as interleukin-6 and tumor necrosis factor-α in macrophage-like RAW264.7 cells and mouse bone marrow primarily differentiated macrophages than did papaverine. However, the inhibitory effect of trimebutine on the interaction of HMGB1 and RAGE was weaker than that of papaverine. Importantly, mechanism-of-action analyses revealed that trimebutine strongly inhibited the activation of RAGE downstream inflammatory signaling pathways, especially the activation of extracellular signal-regulated kinase 1 and 2 (ERK1/2), which are mediator/effector kinases recruited to the intracellular domain of RAGE. Consequently, the activation of Jun amino terminal kinase, which is an important effector kinase for the up-regulation of pro-inflammatory cytokines, was inhibited. Taken together, these results suggest that trimebutine may exert its suppressive effect on the HMGB1-RAGE inflammatory signal pathways by strongly blocking the recruitment of ERK1/2 to the intracellular tail domain of RAGE in addition to its weak inhibition of the extracellular interaction of HMGB1 with RAGE. Thus, trimebutine may provide a unique scaffold for the development of novel dual inhibitors of RAGE for inflammatory diseases.


Assuntos
Proteína HMGB1/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Trimebutina/farmacologia , Animais , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Interleucina-6/metabolismo , Janus Quinases/antagonistas & inibidores , Macrófagos , Camundongos , Papaverina/química , Papaverina/farmacologia , Células RAW 264.7 , Trimebutina/química , Fator de Necrose Tumoral alfa/metabolismo
7.
Bioorg Med Chem ; 28(3): 115249, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31879180

RESUMO

Poly(ADP-ribose) glycohydrolase (PARG) plays an essential role in poly(ADP-ribose) (PAR) turnover, and thereby regulating DNA transactions, such as DNA repair, replication, transcription and recombination. Here, we examined the inhibitory activities of 6-hydroxy-3H-xanthene-3-one (HXO) derivatives and analyzed their binding modes in the active site of PARG by in silico docking study. Among the derivatives, Rose Bengal was found to be the most potent inhibitor of PARG and its halogen groups were revealed to cooperatively potentiate the inhibitory activity. Importantly, the binding mode of Rose Bengal occupied the active site of PARG revealed the presence of unique "Sandwich" residues of Asn869 and Tyr792, which enable the inhibitor to bind tightly with the active pocket. This sandwich interaction could stabilize the π-π interactions of HXO scaffold with Phe902 and Tyr795. In addition, to increase the binding affinity, the iodine and chlorine atoms of this inhibitor could contribute to the inducing of favorable disorders, which promote an entropy boost on the active site of PARG for structural plasticity, and making the stable configuration of HXO scaffold in the active site, respectively, as judged by the analysis of binding free energy. These results provide new insights into the active site of PARG and an additional opportunity for designing selective PARG inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Simulação de Acoplamento Molecular , Xantenos/farmacologia , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Glicosídeo Hidrolases/metabolismo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Xantenos/química
8.
Molecules ; 25(16)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785052

RESUMO

Inhibition of nicotinamide phosphoribosyltransferase (NAMPT) is an attractive therapeutic strategy for targeting cancer metabolism. So far, many potent NAMPT inhibitors have been developed and shown to bind to two unique tunnel-shaped cavities existing adjacent to each active site of a NAMPT homodimer. However, cytotoxicities and resistances to NAMPT inhibitors have become apparent. Therefore, there remains an urgent need to develop effective and safe NAMPT inhibitors. Thus, we designed and synthesized two close structural analogues of NAMPT inhibitors, azaindole-piperidine (3a)- and azaindole-piperazine (3b)-motif compounds, which were modified from the well-known NAMPT inhibitor FK866 (1). Notably, 3a displayed considerably stronger enzyme inhibitory activity and cellular potency than did 3b and 1. The main reason for this phenomenon was revealed to be due to apparent electronic repulsion between the replaced nitrogen atom (N1) of piperazine in 3b and the Nδ atom of His191 in NAMPT by our in silico binding mode analyses. Indeed, 3b had a lower binding affinity score than did 3a and 1, although these inhibitors took similar stable chair conformations in the tunnel region. Taken together, these observations indicate that the electrostatic enthalpy potential rather than entropy effects inside the tunnel cavity has a significant impact on the different binding affinity of 3a from that of 3b in the disparate enzymatic and cellular potencies. Thus, it is better to avoid or minimize interactions with His191 in designing further effective NAMPT inhibitors.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/química , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Sítios de Ligação , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Indóis/química , Cinética , Simulação de Acoplamento Molecular , Nicotinamida Fosforribosiltransferase/metabolismo , Piperazina/química , Piperidinas/química
9.
Biochem Biophys Res Commun ; 511(3): 665-670, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30826057

RESUMO

The interaction of high mobility group box 1 (HMGB1), which is secreted from immune and dying cells during cellular infection and injury, and receptor for advanced glycation end-products (RAGE) appears to be critical for acute and chronic inflammatory disorders. Here we designed a unique cyclic ß-hairpin peptide (Pepb2), which mimics the predicted RAGE-binding domain of HMGB1. Pepb2 competitively inhibited HMGB1/RAGE interaction. We then identified papaverine as a Pepb2 mimetic by in silico 3D-structural similarity screening from the DrugBank library. Papaverine was found to directly inhibit HMGB1/RAGE interaction. It also suppressed the HMGB1-mediated production of pro-inflammatory cytokines, IL-6 and TNF-α, in mouse macrophage-like RAW264.7 cells and bone marrow-derived macrophages. In addition, papaverine attenuated mortality in cecal ligation puncture-induced sepsis model mice. Taken together, these findings indicate that papaverine could become a useful therapeutic against HMGB1/RAGE-mediated sepsis and other inflammatory diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Proteína HMGB1/antagonistas & inibidores , Inflamação/tratamento farmacológico , Papaverina/uso terapêutico , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Sepse/tratamento farmacológico , Animais , Feminino , Proteína HMGB1/imunologia , Inflamação/complicações , Inflamação/imunologia , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos ICR , Células RAW 264.7 , Receptor para Produtos Finais de Glicação Avançada/imunologia , Sepse/complicações , Sepse/imunologia , Fator de Necrose Tumoral alfa/imunologia
10.
Neurosurg Rev ; 41(2): 641-647, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28956184

RESUMO

We have previously reported that reliable detection of 2-hydroxyglutarate (2HG) in isocitrate dehydrogenase (IDH)-mutant WHO grade 2 and 3 gliomas is possible utilizing 3.0-T single-voxel magnetic resonance spectroscopy (SVMRS). We set out to determine whether the same method could be applied to detect 2HG in IDH-mutant glioblastoma. Forty-four patients harboring glioblastoma underwent pre-operative MRS evaluation to detect 2HG and other metabolites. Presence of IDH-mutations was determined by IDH1 R132H immunohistochemical analysis and DNA sequencing of surgically obtained tissues. Six out of 44 (13.6%) glioblastomas were IDH-mutant. IDH-mutant glioblastoma exhibited significantly higher accumulation of 2HG (median 3.191 vs. 0.000 mM, p < 0.0001, Mann-Whitney test). A cutoff of 2HG = 0.897 mM achieved high sensitivity (100.0%) and specificity (92.59%) in determining IDH-mutation in glioblastoma. Glioblastoma with high 2HG accumulation did not have significantly longer overall survival than glioblastoma with low 2HG accumulation (p = 0.107, log-rank test). Non-invasive and reliable detection of 2HG in IDH-mutant glioblastoma was possible by 3.0-T SVMRS.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Glutaratos/metabolismo , Isocitrato Desidrogenase/genética , Espectroscopia de Ressonância Magnética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Criança , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
11.
BMC Genet ; 18(1): 69, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28732471

RESUMO

BACKGROUND: Neuregulin 3 (NRG3) plays a key role in central nervous system development and is a strong candidate for human mental disorders. Thus, genetic variation in NRG3 may have some impact on a variety of phenotypes in non-mammalian vertebrates. Recently, genome-wide screening for short insertions and deletions in chicken (Gallus gallus) genomes has provided useful information about structural variation in functionally important genes. NRG3 is one such gene that has a putative frameshift deletion in exon 2, resulting in premature termination of translation. Our aims were to characterize the structure of chicken NRG3 and to compare expression patterns between NRG3 isoforms. RESULTS: Depending on the presence or absence of the 2-bp deletion in chicken NRG3, 3 breeds (red junglefowl [RJF], Boris Brown [BB], and Hinai-jidori [HJ]) were genotyped using flanking primers. In the commercial breeds (BB and HJ), approximately 45% of individuals had at least one exon 2 allele with the 2-bp deletion, whereas there was no deletion allele in RJF. The lack of a homozygous mutant indicated the existence of duplicated NRG3 segments in the chicken genome. Indeed, highly conserved elements consisting of exon 1, intron 1, exon 2, and part of intron 2 were found in the reference RJF genome, and quantitative PCR detected copy number variation (CNV) between breeds as well as between individuals. The copy number of conserved elements was significantly higher in chicks harboring the 2-bp deletion in exon 2. We identified 7 novel transcript variants using total mRNA isolated from the amygdala. Novel isoforms were found to lack the exon 2 cassette, which probably harbored the premature termination codon. The relative transcription levels of the newly identified isoforms were almost the same between chick groups with and without the 2-bp deletion, while chicks with the deletion showed significant suppression of the expression of previously reported isoforms. CONCLUSIONS: A putative frameshift deletion and CNV in chicken NRG3 are structural mutations that occurred before the establishment of commercial chicken lines. Our results further suggest that the putative frameshift deletion in exon 2 may potentially affect the expression level of particular isoforms of chicken NRG3.


Assuntos
Proteínas Aviárias/genética , Variações do Número de Cópias de DNA , Mutação da Fase de Leitura , Perfilação da Expressão Gênica/métodos , Neurregulinas/genética , Deleção de Sequência , Animais , Sequência de Bases , Galinhas , Éxons , Fenótipo , Isoformas de Proteínas/genética
12.
Bioorg Med Chem Lett ; 27(13): 2868-2872, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28495084

RESUMO

So far, many inhibitors of tyrosinase have been discovered for cosmetic and clinical agents. However, the molecular mechanisms underlying the inhibition in the active site of tyrosinase have not been well understood. To explore this problem, we examined here the inhibitory effects of 4'-hydroxylation and methoxylation of phenylbenzoic acid (PBA) isomers, which have a unique scaffold to inhibit mushroom tyrosinase. The inhibitory effect of 3-PBA, which has the most potent inhibitory activity among the isomers, was slightly decreased by 4'-hydroxylation and further decreased by 4'-methoxylation against mushroom tyrosinase. Surprisingly, 4'-hydroxylation but not methoxylation of 2-PBA appeared inhibitory activity. On the other hand, both 4'-hydroxylation and methoxylation of 4-PBA increased the inhibitory activity against mushroom tyrosinase. In silico docking analyses using the crystallographic structure of mushroom tyrosinase indicated that the carboxylic acid or 4'-hydroxyl group of PBA derivatives could chelate with cupric ions in the active site of mushroom tyrosinase, and that the interactions of Asn260 and Phe264 in the active site with the adequate-angled biphenyl group are involved in the inhibitory activities of the modified PBAs, by parallel and T-shaped π-π interactions, respectively. Furthermore, Arg268 could fix the angle of the aromatic ring of Phe264, and Val248 is supposed to interact with the inhibitors as a hydrophobic manner. These results may enhance the structural insight into mushroom tyrosinase for the creation of novel tyrosinase inhibitors.


Assuntos
Agaricales/enzimologia , Compostos de Bifenilo/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Domínio Catalítico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Relação Estrutura-Atividade
13.
Bioorg Med Chem ; 24(18): 4509-4515, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27507110

RESUMO

Tyrosinase is known as the key enzyme for melanin biosynthesis, which is effective in preventing skin injury by ultra violet (UV). In past decades, tyrosinase has been well studied in the field of cosmetics, medicine, agriculture and environmental sciences, and a lot of tyrosinase inhibitors have been developed for their needs. Here, we searched for new types of tyrosinase inhibitors and found phenylbenzoic acid (PBA) as a unique scaffold. Among three isomers of PBA, 3-phenylbenzoic acid (3-PBA) was revealed to be the most potent inhibitor against mushroom tyrosinase (IC50=6.97µM, monophenolase activity; IC50=36.3µM, diphenolase activity). The kinetic studies suggested that the apparent inhibition modes for the monophenolase and diphenolase activities were noncompetitive and mixed type inhibition, respectively. Analyses by in silico docking studies using the crystallographic structure of mushroom tyrosinase indicated that the carboxylic acid group of the 3-PBA could adequately bind to two cupric ions in the tyrosinase. To prove this hypothesis, we examined the effect of modification of the carboxylic acid group of the 3-PBA on its inhibitory activity. As expected, the esterification abrogated the inhibitory activity. These observations suggest that 3-PBA is a useful lead compound for the generation of novel tyrosinase inhibitors and provides a new insight into the molecular basis of tyrosinase catalytic mechanisms.


Assuntos
Benzoatos/química , Benzoatos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Humanos , Concentração Inibidora 50 , Cinética , Modelos Moleculares , Estrutura Molecular , Monofenol Mono-Oxigenase/química , Oxirredução
14.
BMC Genomics ; 15: 900, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25318583

RESUMO

BACKGROUND: Eukaryotic promoters are regions containing various sequence motifs necessary to control gene transcription. Much evidence has emerged showing that structural and/or contextual changes in regulatory elements can critically affect cis-regulatory activity. As sequence motifs can be key factors in maintaining complex promoter architectures, one effective approach to further understand the evolution of promoter regions in vertebrates is to compare the abundance and distribution patterns of sequence motifs in these regions between divergent species. When compared with mammals, the chicken (Gallus gallus) has a very different genome composition and sufficient genomic information to make it a good model for the exploration of promoter structure and evolution. RESULTS: More than 10% of chicken genes contained short tandem repeat (STR) in the region 2 kb upstream of promoters, but the total number of STRs observed in chicken is approximately half of that detected in human promoters. In terms of the STR motif frequencies, chicken promoter regions were more similar to other avian and mammalian promoters than these were to the entire chicken genome. Unlike other STRs, nearly half of the trinucleotide repeats found in promoters partly or entirely overlapped with CpG islands, indicating potential association with nucleosome positions. Moreover, the chicken promoters are abundant with sequence motifs such as poly-A, poly-G and G-quadruplexes, especially in the core region, that are otherwise rare in the genome. Most of sequence motifs showed strong functional enrichment for particular gene ontology (GO) categories, indicating roles in regulation of transcription and gene expression, as well as immune response and cognition. CONCLUSIONS: Chicken promoter regions share some, but not all, of the structural features observed in mammalian promoters. The findings presented here provide empirical evidence suggesting that the frequencies and locations of STR motifs have been conserved through promoter evolution in a lineage-specific manner. Correlation analysis between GO categories and sequence motifs suggests motif-specific constraints acting on gene function.


Assuntos
Galinhas/genética , DNA/química , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Biologia Computacional/métodos , Sequência Conservada , Ilhas de CpG , DNA/análise , Evolução Molecular , Quadruplex G , Humanos , Mamíferos/genética , Repetições de Microssatélites , Poli A/química , Poli G/química
15.
Bioorg Med Chem ; 22(21): 6193-200, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25288494

RESUMO

Tyrosinase inhibitors have become increasingly critical agents in cosmetic, agricultural, and medicinal products. Although a large number of tyrosinase inhibitors have been reported, almost all the inhibitors were unfortunately evaluated by using commercial available mushroom tyrosinase. Here, we examined the inhibitory effects of three isomers of thujaplicin (α, ß, and γ) on human tyrosinase and analyzed their binding modes using homology model and docking studies. As the results, γ-thujaplicin was found to strongly inhibit human tyrosinase with the IC50 of 1.15 µM, extremely superior to a well-known tyrosinase inhibitor kojic acid (IC50 = 571.17 µM). MM-GB/SA binding free energy decomposition analyses suggested that the potent inhibitory activity of γ-thujaplicin may be due to the interactions with His367, Ile368, and Val377 (hot spot amino acid residues) in human tyrosinase. Furthermore, the binding mode of α-thujaplicin indicated that Val377 and Ser380 may cause van der Waals clashes with the isopropyl group of α-thujaplicin. These results provide a novel structural insight into the hot spot of human tyrosinase for the specific binding of γ-thujaplicin and a way to optimize not only thujaplicins but also other lead compounds as specific inhibitors for human tyrosinase in a rational manner.


Assuntos
Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monoterpenos/farmacologia , Tropolona/análogos & derivados , Sequência de Aminoácidos , Humanos , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Alinhamento de Sequência , Relação Estrutura-Atividade , Tropolona/farmacologia
16.
Life (Basel) ; 14(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38541737

RESUMO

Nicotinamide adenine dinucleotide (NAD+) plays a pivotal role in various physiological processes within mammalian cells, including energy metabolism, redox homeostasis, and genetic regulation. In the majority of mammalian cellular contexts, NAD+ biosynthesis primarily relies on vitamin B3, including nicotinamide (NAM) and nicotinic acid (NA). The concept of NAD+ augmentation therapy has recently emerged as a promising strategy to mitigate aging-associated phenomena, termed rejuvenation. Despite the involvement of diverse enzymatic cascades in NAD+ biosynthesis, certain cellular environments exhibit deficiencies in specific enzymes, suggesting cell type-dependent variability in optimal NAD+ precursor selection. However, the optimization of NAD+ precursors for topical formulations has received scant attention thus far. In the present investigation, we sought to delineate the most efficacious precursor for augmenting NAD+ levels in human skin keratinocytes. Remarkably, NA supplementation led to a significant 1.3-fold elevation in intracellular NAD+ levels, even in the presence of nicotinamide phosphoribosyltransferase inhibition by FK866. Additionally, NA mononucleotide demonstrated a 1.5-fold increase (but not significant) in NAD+ levels following 100 µM application. Conversely, NAM and its derivatives failed to elicit a NAD+ response in keratinocytes. Notably, NA supplementation elicited up-regulation of mitochondrial superoxide dismutase (SOD2) and sirtuin 3 (SIRT3), indicative of its beneficial impact on mitochondrial function. Furthermore, NA mitigated rotenone-induced mitochondrial reactive oxygen species (ROS) accumulation. Collectively, these findings advocate for the potential utility of NA in topical applications aimed at skin rejuvenation.

17.
J Mol Evol ; 77(5-6): 260-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24193891

RESUMO

Mesotocin is a neurohypophyseal hormone found in some non-mammalian vertebrates, including birds, reptiles, and amphibians. In this study, we identified and characterized 18-amino acid duplications in the C-terminal domain of the mesotocin receptor (MTR), specifically found in Turdus thrushes (Aves: Passeriforms: Turdidae). These duplicated elements are located in the distal part of the C-terminal tails of MTR and consist of amino acids that are highly conserved among major vertebrates. Intraspecific polymorphisms in a variable number of tandem duplications are commonly found in East Eurasian Turdus, but not in any other genus of Turdidae. Moreover, the genus Turdus can be further classified into 2 groups according to the presence or absence of a 3-amino acid deletion just adjacent to the putative palmitoylation site in the cytoplasmic C-terminal tail. The phylogeny presented here strongly supports the conspecific group of 4 East Eurasian thrushes (Turdus pallidus, T. chrysolaus, T. obscurus, and T. celaenops). Our findings, therefore, provide a new synapomorphy that can be used for phylogenetic assumptions and shed a light on the history of diversification within Eurasian Turdus clades.


Assuntos
Passeriformes/genética , Filogenia , Polimorfismo Genético/genética , Receptores do Hormônio Hipofisário/genética , Sequências de Repetição em Tandem/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA/genética , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Análise para Determinação do Sexo , Especificidade da Espécie
18.
Biosci Biotechnol Biochem ; 77(5): 971-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23649256

RESUMO

We investigated the role of nitric oxide (NO) in vascular endothelial growth factor (VEGF) expression in the rat placenta. A nitric oxide synthase (NOS) inhibitor, N(G)-nitro-L-arginine-methyl ester (L-NAME), was constantly infused into pregnant rats 6-24 h before sacrifice on gestational day (GD) 15.5. NO production declined to about 15% of the control level as monitored by NO trapping and electron paramagnetic resonance spectroscopy. VEGF mRNA expression was temporally decreased by L-NAME, but recovered to normal levels after 24 h of treatment, whereas hypoxia inducible factor (HIF)-1α and induced NOS (iNOS) expression increased. VEGF expression decreased significantly in placental explants after 6 h of co-treatment with L-NAME and lipopolysaccharide, an iNOS inducer. Our data indicate that NO induce VEGF expression in vivo and in vitro in the rat placenta, suggesting that peaked NO production was maintained by a reciprocal relationship between NO and VEGF via HIF-1α.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Óxido Nítrico/farmacologia , Placenta/efeitos dos fármacos , Placenta/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Gravidez , Ratos , Ratos Wistar , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
19.
Mol Biol Rep ; 39(1): 693-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21625864

RESUMO

Using mitochondrial and nuclear markers species identification was conducted in the case of seized feathers. Earlier, we had sequenced cytochrome c oxidase subunit I (COI) both from 10 seized specimens and 43 validation specimens from captive macaws belonging to 4 Ara species (A. macao, A. chloropterus, A. ararauna, and A. ambiguus) and identified 19 haplotypes based on COI sequences. Species-level identification using Barcode of Life Data Systems showed that seized feathers shared the highest similarity with scarlet macaws (A. macao), and this result was supported by the tree-base identification with high bootstrap values. Moreover, microsatellite profiles in AgGT17 locus showed that patterns of allelic distribution in the seized feathers were apparently distinct from those of red-and-green macaw (A. chloropterus), but were overlapped with those of A. macao, suggesting that all of seized feathers were derived from several individuals of A. macao. We also determined the parentage of hybrid macaws by the combination of COI barcodes and microsatellite profiles. The technique presented here will contribute to forensic identification and future conservation of large macaws that have been lost due to deforestation.


Assuntos
Código de Barras de DNA Taxonômico , Plumas/química , Repetições de Microssatélites/genética , Psittaciformes/genética , Animais , Sequência de Bases , Análise por Conglomerados , Conservação dos Recursos Naturais/métodos , Primers do DNA/genética , Feminino , Haplótipos/genética , Masculino , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
20.
Biochimie ; 192: 13-21, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34536557

RESUMO

Tyrosinase (TYR) is a key enzyme for melanin production. We previously showed that hinokitiol, a naturally occurring seven-membered ring terpenoid, potently inhibits human TYR activity. Interestingly, hinokitiol was recently reported to decrease expression of TYR and microphthalmia-associated transcription factor (MITF), which is a main transcription factor of the TYR gene, in murine melanoma cells. However, the mechanisms by which hinokitiol decreases the intracellular levels of TYR and MITF have not been fully elucidated. Here, we investigated the underlying mechanisms of the decreases using cultured human melanoma cells. As a result, hinokitiol treatment decreased TYR protein level in a time- and dose-dependent manner in G361 human melanoma cells, while MITF protein level was decreased only at higher concentrations after 3 days treatment. Notably, the mRNA levels of TYR and MITF were slightly increased by hinokitiol treatment. Therefore, we focused on the degradation of TYR and MITF in endoplasmic reticulum (ER)-associated protein degradation (ERAD) pathway. Importantly, co-treatment of ERAD inhibitor with hinokitiol restored the protein levels of TYR and MITF to approximately 30% and 20% of total those in untreated control cells, respectively. Hinokitiol affected the ER homeostasis as well as degradation of TYR and MITF in two human melanoma cell lines, G361 and HT-144, but the changes of ER-stress markers under the hinokitiol treatment were different in the two human melanoma cell lines. Taken together, these observations indicate that hinokitiol may induce ER stress and trigger the degradation of unfolded newly synthesizing TYR and MITF via the ERAD pathway.


Assuntos
Degradação Associada com o Retículo Endoplasmático/efeitos dos fármacos , Melanoma/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Monoterpenos/farmacologia , Proteínas de Neoplasias/metabolismo , Tropolona/análogos & derivados , Linhagem Celular Tumoral , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Tropolona/farmacologia
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