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1.
Polymers (Basel) ; 15(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37514432

RESUMO

Robust membrane materials with high efficiency have attracted extensive attention in oil/water separation. In this work, carbon particles via candle combustion were firstly adsorbed on the surface of stainless steel meshes (SSMs), which formed a thin hydrophobic coating, and a rough structure was then constructed through chemical vapor deposition and high temperature calcination, with the resultant SSM surface wrapped with uniform silica coating possessing the characteristic of superoleophobicity underwater. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray powder diffraction (XRD) were used to characterize the modified SSMs. The prepared SSMs were superhydrophilic in air, and they had superoleophobicity underwater (157.4°). The separation efficiency of five oil/water mixtures was above 98.8%, and the separation flux was 46,300 L·m-2·h-1. After it was immersed in 1 mol/L NaOH, 1 mol/L HCl and 3.5 wt% NaCl for 24 h, respectively, the efficiency was still above 97.3%. Further immersion in the solution of dopamine and octadecylamine resulted in the transformation of superhydrophililc/superoleophobicity-underwater SSMs to superhydrophobic SSMs, and the resultant SSMs with reverse surface wettability was also used for the oil/water separation with good separation efficiency and separation flux.

2.
Front Aging Neurosci ; 14: 842380, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004003

RESUMO

Multiple factors such as genes, environment, and age are involved in developing Parkinson's disease (PD) pathology. However, how various factors interact to cause PD remains unclear. Here, 3-month and 9-month-old hα-syn+⁣/- mice were treated with low-dose rotenone for 2 months to explore the mechanisms that underline the environment-gene-age interaction in the occurrence of PD. We have examined the behavior of mice and the PD-like pathologies of the brain and gut. The present results showed that impairments of the motor function and olfactory function were more serious in old hα-syn+/- mice with rotenone than that in young mice. The dopaminergic neuron loss in the SNc is more in old hα-syn+/- mice with rotenone than in young mice. Expression of hα-syn+/- is increased in the SNc of hα-syn+/- mice following rotenone treatment for 2 months. Furthermore, the number of activated microglia cells increased in SNc and accompanied the high expression of inflammatory cytokines, namely, TNF-α and IL-18 in the midbrain of old hα-syn+/- mice treated with rotenone. Meanwhile, we found that after treatment with rotenone, hα-syn positive particles deposited in the intestinal wall, intestinal microflora, and T lymphocyte subtypes of Peyer's patches changed, and intestinal mucosal permeability increased. Moreover, these phenomena were age-dependent. These findings suggested that rotenone aggravated the PD-like pathologies and affected the brain and gut of human α-syn+/- transgenic mice in an age-dependent manner.

3.
Exp Neurol ; 334: 113490, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33007295

RESUMO

Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) have a common pathology. Both diseases are characterized by local deposition of amyloid proteins in the brain or islet organ, but their phenotypes and clinical manifestation vary widely. Although the sources of islet amyloid polypeptide (IAPP) and amyloid beta (Aß) are independent, their fibrillar sequences are highly homologous. The prevalence of AD in T2DM populations is considerably higher than that in the normal population, but a mechanistic linkage remains elusive. Therefore, the present study aimed to explore the effects of Aß42 deposition in the brain on the persistently expression of human IAPP (hIAPP). Additionally, cognitive ability, synaptic plasticity, the state of neural stem cells and mitochondrial function were evaluated at 2 or 6 months after stereotaxically injected the oligomer Aß1-42 into the dentate gyrus of hIAPP (-/+) mice or the wild-type littermates. We found that Aß42 and amylin were co-located in hippocampus and Aß42 levels increased when Aß1-42 was injected in hIAPP transgenic mice compared with that of the wild-type littermates. Furthermore, at 6 months after Aß1-42 injection in hIAPP (-/+) mice, it exhibits exacerbated AD-related pathologies including Aß42 deposition, cognitive impairment, synapse reduction, neural stem cells exhaustion and mitochondrial dysfunction. Our present study suggested that hIAPP directly implicated the Aß42 production and deposition as an important linkage between T2DM and AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/toxicidade , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Fragmentos de Peptídeos/toxicidade , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/administração & dosagem , Animais , Linhagem Celular , Disfunção Cognitiva/genética , Giro Denteado/metabolismo , Giro Denteado/patologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/administração & dosagem , Ligação Proteica/fisiologia
4.
Biochim Biophys Acta Gen Subj ; 1864(1): 129422, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491457

RESUMO

BACKGROUND: Previous studies suggested that fibrillar human IAPP (hIAPP) is more likely to deposit in ß-cells, resulting in ß-cell injury. However, the changes in the conformation of hIAPP in lipid environment and the mechanism involved in ß-cell damage are unclear. METHODS: Synthetic hIAPP was incubated with five types of free fatty acids and phospholipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS), which constitute the cell membrane. Thioflavin-T fluorescence assay was conducted to analyze the degree of hIAPP fibrosis, and circular dichroism spectroscopy was performed to detect the ß-fold formation of hIAPP. Furthermore, INS-1 cells were infected with human IAPP delivered by a GV230-EGFP plasmid. The effects of endogenous hIAPP overexpression induced by sodium palmitate on the survival, endoplasmic reticulum (ER) stress, and apoptosis of INS-1 cells were evaluated. RESULTS: The five types of free fatty acids can accelerate the fibrosis of hIAPP. Sodium palmitate also maintained the stability of fibrillar hIAPP. POPS, not POPC, accelerated hIAPP fibrosis. Treatment of INS-1 cells with sodium palmitate increased the expression of hIAPP, activated ER stress and ER stress-dependent apoptosis signaling pathways, and increased the apoptotic rate. CONCLUSION: Free fatty acids and anionic phospholipid can promote ß-fold formation and fibrosis in hIAPP. High lipid induced the overexpression of hIAPP and aggravated ER stress and apoptosis in INS-1 cells, which caused ß-cell death in high lipid environment. GENERAL SIGNIFICANCE: Our study reveals free fatty acids and hIAPP synergistically implicated in endoplasmic reticulum stress and apoptosis of islet ß-cells.


Assuntos
Apoptose/genética , Fibrose/genética , Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Amiloide/genética , Amiloide/metabolismo , Membrana Celular/genética , Membrana Celular/metabolismo , Estresse do Retículo Endoplasmático/genética , Ácidos Graxos não Esterificados/genética , Ácidos Graxos não Esterificados/metabolismo , Fibrose/metabolismo , Fibrose/patologia , Regulação da Expressão Gênica/genética , Humanos , Células Secretoras de Insulina/patologia , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/ultraestrutura , Metabolismo dos Lipídeos/genética , Lipídeos/genética , Ácido Palmítico/metabolismo , Fosfatidilcolinas/genética , Fosfatidilcolinas/metabolismo , Fosfatidilserinas/genética , Fosfatidilserinas/metabolismo , Conformação Proteica em Folha beta , Dobramento de Proteína
5.
Cardiovasc Diagn Ther ; 9(3): 239-249, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31275814

RESUMO

BACKGROUND: Currently, direct comparative safety between endothelin receptor antagonists (ERAs) in pulmonary arterial hypertension (PAH) is limited. Thus, a systematic review with network analysis was conducted. METHODS: An electronic search was performed for randomized controlled trials (RCTs) that reported the interested safety data (abnormal liver function, peripheral edema, and anemia) of ERAs in PAH. Risk ratios (RRs) with their confidence intervals (CIs) and the surface under the cumulative ranking curve (SUCRA) were calculated using a network analysis. RESULTS: Ten RCTs involving 2,288 patients were included. Compared with placebo, bosentan (RR, 2.93; 95% CI, 1.78-4.84) significantly increased the risk of abnormal liver function, ambrisentan (RR, 1.62; 95% CI, 1.23-2.13) significantly increased the risk of peripheral edema, and macitentan (RR, 3.42; 95% CI, 1.65-7.07) significantly increased the risk of anemia. SUCRA analysis suggested that bosentan 125 mg twice daily had the highest risk of abnormal liver function; ambrisentan 10 mg once daily had the highest risk of peripheral edema; macitentan 10 mg once daily had the highest risk of anemia. CONCLUSIONS: Abnormal liver function (bosentan), peripheral edema (ambrisentan), and anemia (macitentan) were the safety indicators of ERAs in patients with PAH. Different monitoring parameters should be considered for individual ERA.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(2): 515-8, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-27151021

RESUMO

OBJECTIVE: To investigate the potential value of combined examinations of peripheral blood smear, bone marrow smear, bone marrow biopsy, chromosome banding analysis and flow cytometry (FCM) in the diagnoisis of myelodysplastic syndromes. METHODS: A total of 105 MDS patients who were admitted in our hospital from May 2013 to May 2015 and were diagnosed as MDS according to the criteria formulated by WHO were enrolled in this study. The accordance rate of diagnosis by the double test (peripheral blood smear plus bone marrow smear), triple test (above mentioned 2 tests plus bone marrow biopsy), quadruple test (above 3 tests plus chromosome banding analysis), and quintuple test (above 4 plus FCM) was amalyzed and compared. RESULTS: Among the 105 MDS patients, the diagnosis accordance rate was 70.48% for double tests, while 83.81%, 84.76% and 93.33% for triple, quadruple and quintuplet tests, respectively which were significantly higher than that for double tests (peripheral blood smear plus bone marrow smear) (P < 0.05). CONCLUSION: The combined examination of the 5 methods can improve the accuracy of MDS diagnosis.


Assuntos
Biópsia , Exame de Medula Óssea , Bandeamento Cromossômico , Citometria de Fluxo , Síndromes Mielodisplásicas/diagnóstico , Humanos
7.
Dongwuxue Yanjiu ; 34(2): 97-102, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23572358

RESUMO

In most Old world monkey species, TRIM5α plays a role in combating retroviruses and restricting HIV-1. Alongside TRIM5α, the TRIMCyp fusion gene formed by the retrotransposition of a CypA pseudogene cDNA to 3' terminal or 3'-UTR of TRIM5 gene in these monkeys has become a key research area in anti HIV-1 factors. The regional differences, gene frequencies, genotypes, and retrovirus restrictive activities of TRIMCyp vary among different primate species. While the frequencies of cynomolgus TRIMCyp have been studied in several areas of Southeast Asia, the frequency and prevalence of cynomolgus TRIMCyp in China remains unclear. In this study, we screened 1, 594 cynomolgus samples from 11 monkey manufacturers located across 5 provinces in China. Our results showed that the frequencies of TRIMCyp range from 7.65% to 19.79%, markedly lower than the frequencies found in monkey species in the Philippines, Malaysia and Indonesia (ranging from 34.85% to 100%). We speculate that potentially the latter were isolated groups established since 1978. The NE haplotype frequencies of cynomolgus TRIMCyp were 4.93% in China, also significantly lower than those found in species in the Philippines, Malaysia and Indonesia (from 11.1% to 14.3%). Our research provides interesting findings that contribute towards a more firm basis of further studies of HIV-1 animal models and relevant pathogenesis.


Assuntos
Frequência do Gene , Macaca fascicularis/genética , Proteínas Mutantes Quiméricas/genética , Animais , Ásia , China , Genótipo
8.
Immunogenetics ; 65(3): 185-93, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23233150

RESUMO

The tripartite motif protein (TRIM)5α/CypA fusion protein TRIMCyp in Old World monkeys is generally considered unable to restrict HIV-1 replication. Monkeys with TRIMCyp can serve as a unique animal model for studies of HIV-1 infection. The present study investigated the distribution and expression status of TRIMCyp in four species of macaques originating from China and its borderlands: pigtail macaques (Macaca nemestrina), rhesus macaques (Macaca mulatta), long-tailed macaques (Macaca fascicularis), and Tibetan macaques (Macaca thibetana). The results revealed that the frequencies of the TRIMCyp genotype were significantly different among different species and even within different populations of the same species. Interestingly, the TRIMCyp genotype was more prevalent among macaques originating from Yunnan and surrounding regions than those from other regions of China. Importantly, TRIMCyp individuals were first identified in Chinese M. mulatta originating from Yunnan, although multiple earlier studies failed to find CypA retrotransposition in this subspecies. Furthermore, TRIMe7-CypA, one of the splicing isoforms of the TRIMCyp transcript was expressed in M. nemestrina and M. mulatta but not M. fascicularis. The intra- and interspecies polymorphisms in the deduced TRIMCyp amino acid sequences of these macaques were also analyzed. Taken together, the data in this study provide important information about the genomic background of TRIMCyp among major species of Chinese macaques.


Assuntos
Proteínas de Transporte/genética , Macaca/genética , Proteínas Mutantes Quiméricas/genética , Proteínas/genética , Retroelementos/genética , Distribuição Animal , Animais , Sequência de Bases , China , Resistência à Doença/genética , Mutação da Fase de Leitura , Genótipo , Infecções por HIV/genética , HIV-1 , Macaca fascicularis/genética , Macaca mulatta/genética , Macaca nemestrina/genética , Dados de Sequência Molecular , Polimorfismo Genético , Isoformas de Proteínas/genética , Pseudogenes , Especificidade da Espécie , Ubiquitina-Proteína Ligases
9.
Yi Chuan ; 34(5): 526-32, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22659424

RESUMO

Worldwide influenza caused by influenza virus is a respiratory disease which threats the public health by seasonal epidemics or global influenza outbreak. Vaccines and drugs are current therapies, but there are many restricted factors such as neurotoxicity, side effects of gastrointestinal, and drug resistance. New technologies, particularly RNAi mediated by small RNAs, has become a potential and robust method in influenza antiviral research for its high efficiency, specific, and speedy. Following the spread and epidemic of the influenza virus, application of small RNAs into influenza antiviral research has been reported increasingly. The small RNAs, PA-2087, NP-1496, and M-950, which targets PA, NP, and M2 genes, respectively, are the most effective anti-influenza siRNAs up to now. siRNA of targeting conservative region of different influenza viral genes has broader effect on virus inhibition. The combination of siRNAs of targeting different genes can achieve better virus inhibition. In this review, we mainly described the progress of siRNAs and miRNAs for anti-influenza virus, and the prospects and hurdles of influenza RNAi therapy as well.


Assuntos
Influenza Humana/terapia , MicroRNAs/fisiologia , RNA Interferente Pequeno/genética , Humanos , Interferência de RNA
10.
Hum Immunol ; 73(5): 547-53, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22365968

RESUMO

High-frequency alleles and/or co-occurring human leukocyte antigen (HLA) alleles across loci appear to be more important than individual alleles, because they might be markers of disease risk that have clinical value as biomarkers for targeted screening or the development of new therapies. To better elucidate the major histocompatibility complex background and to facilitate the experimental use of cynomolgus macaques, Mafa-B, Mafa-DQB1, and Mafa-DRB alleles were characterized and their combinations were investigated from 30 macaques of Vietnamese origin by cloning and sequencing. A total of 48 Mafa-B, 22 Mafa-DQB1, and 42 Mafa-DRB alleles, were detected in this study, respectively. In addition, two Mafa-DQB1 and eight Mafa-DRB alleles represented novel sequences that had not been documented in earlier studies. Our results also showed that the macaque from Vietnam might be valuable because >30% of the test animals possessed Mafa-DRB*w304 (30%) and -DQB1*0616 (30%). We report that the combination of major histocompatibility complex (MHC) class I and II alleles, including the combination of DRB3*0403-DRB*w304, DRB1*1013-DRB*w304, and Mafa-B*007:01:01-DRB*w304, which was in 17%, 13%, and 13% of the animals, respectively. Interesting, more than two Mafa-DQB1 alleles detected in one animal in this study suggest that Mafa-DQB1, like Mafa-DRB, might be a duplication in the chromosome, which have ever been documented in cynomolgus monkeys but has not yet been observed in rhesus macaques or other primates. Our results for the high frequency of commonly co-occurring MHC alleles across loci in a cohort of the Vietnamese cynomolgus macaque emphasized the value of this species as a model for biomedical research.


Assuntos
Alelos , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Macaca fascicularis/genética , Animais , Clonagem Molecular , Duplicação Gênica , Frequência do Gene , Loci Gênicos , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Macaca fascicularis/imunologia , Modelos Biológicos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Análise de Sequência de DNA , Vietnã
11.
Immunogenetics ; 63(3): 155-66, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21132285

RESUMO

Major histocompatibility complex (MHC) molecules play an important role in the susceptibility and/or resistance to many diseases. To gain an insight into the MHC background and to facilitate the experimental use of cynomolgus macaques, the second exon of the MhcMafa-DOB, -DPB1, and -DQB1 genes from 143 cynomolgus macaques were characterized by cloning to sequencing. A total of 16 Mafa-DOB, 16 Mafa-DPB1, and 34 Mafa-DQB1 alleles were identified, which revealed limited, moderate, and marked allelic polymorphism at DOB, DPB1, and DQB1, respectively, in a cohort of cynomolgus macaques of Vietnamese origin. In addition, 16 Mafa-DOB, 5 Mafa-DPB1, and 8 Mafa-DQB1 alleles represented novel sequences that had not been reported in earlier studies. Almost of the sequences detected at the DOB and DQB1 locus in the present study belonged to DOB*01 (100%) and DQB1*06 (62%) lineages, respectively. Interestingly, four, three, and one high-frequency alleles were detected at Mafa-DOB, -DPB1, and -DQB1, respectively, in this monkeys. The alleles with the highest frequency among these monkeys were Mafa-DOB*010102, Mafa-DPB1*13, and Mafa-DQB1*0616, and these were found in 33 (25.6%) of 129 monkeys, 32 (31.37%) of 102 monkeys, and 30 (31%) of 143 monkeys, respectively. The high-frequency alleles may represent high priority targets for additional characterization of immune function. We also carried out evolutionary and population analyses using these sequences to reveal population-specific alleles. This information will not only promote the understanding of MHC diversity and polymorphism in the cynomolgus macaque but will also increase the value of this species as a model for biomedical research.


Assuntos
Genes MHC da Classe II , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Sequência de Aminoácidos , Animais , Frequência do Gene , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/genética , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência
12.
Yi Chuan ; 31(10): 1013-9, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19840923

RESUMO

Adiponectin, a cytokine hormone secreted exclusively by adipose tissue, has key roles in energy homeostasis and in metabolism of glucose and lipid. Adiponectin expression was negatively associated with obesity. Many CpG sites were found at the adiponectin promoter region (nucleotides -1500 approximately -1350 bp). To further understand the regulation of pig adiponectin expression, the methylation status of pig adiponectin promoter and its mRNA expression were analyzed by methylation special PCR (MSP) and real-time PCR. At the adiponectin promoter region where CG enriches (nucleotides -1500 approximately -1350 bp), the percentage of demethylation in Changbai pigs was 83%; and the percentages of demethylation in Lantang pigs at 90-day-old and adult stages were 33% and 100%, respectively. The process of methylation and demethyla-tion mainly occurred in certain CpG sites. In muscle tissues, the promoter hypermethylation status of adiponectin gene was detected, which was consistent with the expression of this gene. These results suggested that the methylation of this gene experienced a dynamic process, with the development of individuals, which agreed with the fluctuating trend of gene expression.


Assuntos
Adiponectina/genética , Metilação de DNA/genética , Regulação da Expressão Gênica , Regiões Promotoras Genéticas/genética , Animais , Ilhas de CpG/genética , Feminino , Masculino , Músculos/metabolismo , Reação em Cadeia da Polimerase , Suínos
13.
Biotechnol Lett ; 31(7): 1025-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19330484

RESUMO

A major problem when xylose is used for ethanol production is the intercellular redox imbalance arising from different coenzyme specificities of xylose reductase (XR) and xylitol dehydrogenase. The residue Lys21 in XR from Pichia stipitis was subjected to site-directed mutagenesis to alter its coenzyme specificity. The N272D mutant exhibited improved catalytic efficiency when NADH was the coenzyme. Both K21A and K21A/N272D preferred NADH to NADPH, their catalytic efficiencies for NADPH were almost zero. The catalytic efficiency of K21A/N272D for NADH was almost 9-fold and 2-fold that of K21A and the wild-type enzyme, respectively. Complete reversal of coenzyme specificity toward NADH and improved catalytic efficiency were achieved.


Assuntos
Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Coenzimas/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mutagênese Sítio-Dirigida , Pichia/enzimologia , Substituição de Aminoácidos/genética , Proteínas Motores Moleculares , NAD/farmacologia , NADP/farmacologia , Pichia/genética , Estrutura Terciária de Proteína
14.
Biochem Genet ; 46(5-6): 369-79, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18278550

RESUMO

The secretogranin II (SCG2) gene is associated with the synthesis and secretion of follicle-stimulating hormone and luteinizing hormone. In the present study, we have determined the complete cDNA sequence of pig SCG2, which was submitted to GenBank with accession no. AY870646. Its complete open reading frame of 1,851 nucleotides encodes 616 amino acids. The predicted protein shares 80-87% identity with mouse, human, and bovine SCG2 proteins, and all four species share almost complete identity in the secretoneurin and EM66 domains. Pig SCG2 is a protein of 589 amino acids and 68,132 Da, preceded by a signal peptide of 27 residues. It contains nine pairs of dibasic residues, which are used as potential cleavage sites for generation of physiologically active peptides. Analysis of the SCG2 gene across the INRA-Minnesota porcine radiation hybrid panel indicates close linkage with microsatellite marker SW2608, located on Sus scrofa chromosome 15 (SSC15) q25, which harbors several QTL for ovulation rate and meat quality. Comparative sequencing and EST analysis revealed nine SNPs in porcine SCG2 cDNA, including seven SNPs in the coding region and two SNPs in the 3' UTR. Four nonsynonymous SNPs (G622A, G1671T, C1718T, and A1790C) resulted in amino acid substitutions of Ala-->Thr, Glu-->Asp, Pro-->Leu, and Asn-->Thr, respectively.


Assuntos
Polimorfismo Genético , Secretogranina II/genética , Sus scrofa/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromossomos de Mamíferos/genética , Clonagem Molecular , Feminino , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência
15.
Biochem Biophys Res Commun ; 359(2): 323-9, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17544374

RESUMO

NAD(P)H-dependent d-xylose reductase is a homodimeric oxidoreductase that belongs to the aldo-keto reductase superfamily. The enzyme has the special function to catalyze the first step in the assimilation of xylose into yeast metabolic pathways. Performing this function via reducing the open chain xylose to xylitol, the xylose reductase of Pichia stipitis is one of the most important enzymes that can be used to construct recombinant Saccharomyces cerevisiae strain for utilizing xylose and producing alcohol. To investigate into the interaction mechanism of the enzyme with its ligand NAD and NADP, the 3D structure was developed for the NAD(P)H-dependent d-xylose reductase from P. stipitis. With the 3D structure, the molecular docking operations were conducted to find the most stable bindings of the enzyme with NAD and NADP, respectively. Based on these results, the binding pockets of the enzyme for NAD and NADP have been explicitly defined. It has been found that the residues in forming the binding pockets for both NAD and NADP are almost the same and mainly hydrophilic. These findings may be used to guide mutagenesis studies, providing useful clues to modify the enzyme to improve the utilization of xylose for producing alcohol. Also, because human aldose reductases have the function to reduce the open chain form of glucose to sorbitol, a process physiologically significant for diabetic patients at the time that their blood glucose levels are elevated, the information gained through this study may also stimulate the development of new strategies for therapeutic treatment of diabetes.


Assuntos
Aldeído Redutase/química , NADP/química , NAD/química , Pichia/enzimologia , Álcoois , Sequência de Aminoácidos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Ligação Proteica , Prótons , Homologia de Sequência de Aminoácidos
16.
Yi Chuan Xue Bao ; 32(4): 372-7, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16011028

RESUMO

Four breeds of chickens (White Leghorn, Yangshan, Taihe Silkies, White Recessive Rocks) with different egg production were applied to screen potential single nucleotide polymorphisms (SNPs) related to reproduction trait in distal part region of prolactin gene based on DNA pooling and sequencing. Eight SNPs (C2402T, T-2192C, C-2161G, C-2134G, C-2062G, G-2040A, A-1944G and C-1884A) were found successfully in the fragment of 1 028 bp at the distal part of 5'flanking region. Moreover,a simple and rapid method to estimate allelic frequencies of SNPs in each breed by calculating the ratio of allele peak heights was introduced here. The accuracies of estimation for the allelic frequencies of C-2402T, C-2161G, C-1884A, C-2062G and G-2040A were verified by comparing with the results of PCR-RFLP or PCR-SSCP.


Assuntos
Galinhas/genética , DNA/genética , Polimorfismo de Nucleotídeo Único , Prolactina/genética , Região 5'-Flanqueadora , Animais , Sequência de Bases , Galinhas/classificação , DNA/química , Frequência do Gene , Genoma , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Locos de Características Quantitativas , Análise de Sequência de DNA
17.
Yi Chuan ; 27(2): 208-14, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15843347

RESUMO

Four chicken breeds (White Leghorn, Yangshan, Taihe Silkies, White Recessive Rocks) with different reproduction were applied to screen potential SNPs related to laying performance in the 5' flanking region, exon region and partial intron region of chicken prolactin (cPRL) gene. Totally almost 4500 bp were screened rapidly based on DNA pooling and sequencing, and thirteen single nucleotide polymorphisms (SNPs) and two indels (24 bp and 15 bp) were found, including nine SNPs and two indels in the 5' flanking region, one SNP in Exon 2, two SNPs in Exon 5 and one SNP in Intron 2 respectively. Furthermore, 5' flanking region of cPRL gene was analyzed by the website of http://motif.genome.ad.jp/. A possible Evi-1 binding site (score 93) was found in White Leghorn cPRL gene because of the 24 bp insertion, another possible C/EBPbeta binding site (score 94) was found in Yangshan cPRL gene because of the variation of C-2402T. Further studies need to be carried out to verify their effects on the expression of cPRL gene, the broodiness and laying performance of chickens.


Assuntos
Galinhas/genética , Biologia Computacional/métodos , Polimorfismo de Nucleotídeo Único , Prolactina/genética , Região 5'-Flanqueadora , Animais , Sequência de Bases , Sítios de Ligação/genética , Galinhas/classificação , Análise Mutacional de DNA , Éxons , Mutação INDEL , Íntrons , Dados de Sequência Molecular , Especificidade da Espécie , Fatores de Transcrição/metabolismo
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