Consulta: creatorFacets:"Chen,Keping"
Registros recuperados: 7
Data/hora: 03/06/2024 08:40:48

Cloning, expression and characterization of alcohol dehydrogenases in the silkworm Bombyx mori
Provedor de dados: 74
Autores: Wang,Nan; Shi,Haifeng; Yao,Qin; Zhou,Yang; Kang,Lequn; Chen,Huiqin; Chen,Keping.
Alcohol dehydrogenases (ADH) are a class of enzymes that catalyze the reversible oxidation of alcohols to corresponding aldehydes or ketones, by using either nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate (NADP), as coenzymes. In this study, a short-chain ADH gene was identified in Bombyx mori by 5'-RACE PCR. This is the first time the coding region of BmADH has been cloned, expressed, purified and then characterized. The cDNA fragment encoding the BmADH protein was amplified from a pool of silkworm cDNAs by PCR, and then cloned into E. coli expression vector pET-30a(+). The recombinant His-tagged BmADH protein was expressed in E. coli BL21 (DE3), and then purified by metal chelating affinity chromatography. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: 5'-RACE PCRADH; Enzymatic activity; Recombinant protein.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200013

Adaptive evolution of the vertebrate skeletal muscle sodium channel
Provedor de dados: 74
Autores: Lu,Jian; Zheng,Jianzhou; Xu,Qinggang; Chen,Keping; Zhang,Chiyu.
Tetrodotoxin (TTX) is a highly potent neurotoxin that blocks the action potential by selectively binding to voltage-gated sodium channels (Na v). The skeletal muscle Na v (Na v1.4) channels in most pufferfish species and certain North American garter snakes are resistant to TTX, whereas in most mammals they are TTX-sensitive. It still remains unclear as to whether the difference in this sensitivity among the various vertebrate species can be associated with adaptive evolution. In this study, we investigated the adaptive evolution of the vertebrate Na v1.4 channels. By means of the CODEML program of the PAML 4.3 package, the lineages of both garter snakes and pufferfishes were denoted to be under positive selection. The positively selected sites identified...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Skeletal muscle voltage-gated Na (Na v1.4) channel; Tetrodotoxin (TTX); Positive selection; Pufferfish; Garter snake.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200026

Molecular evolution of the ent-kaurenoic acid oxidase gene in Oryzeae
Provedor de dados: 74
Autores: Yang,Yanhua; Chen,Keping.
We surveyed the substitution patterns in the ent-kaurenoic acid oxidase (KAO) gene in 11 species of Oryzeae with an outgroup in the Ehrhartoidaea. The synonymous and non-synonymous substitution rates showed a high positive correlation with each other, but were negatively correlated with codon usage bias and GC content at third codon positions. The substitution rate was heterogenous among lineages. Likelihood-ratio tests showed that the non-synonymous/synonymous rate ratio changed significantly among lineages. Site-specific models provided no evidence for positive selection of particular amino acid sites in any codon of the KAO gene. This finding suggested that the significant rate heterogeneity among some lineages may have been caused by variability in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Codon usage bias; Ent-kaurenoic acid oxidase (KAO); Positive selection; Rate heterogeneity; Substitution rate.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000300011

Comparative proteomic analysis of indica and japonica rice varieties
Provedor de dados: 74
Autores: Yang,Yanhua; Zhu,Keming; Xia,Hengchuan; Chen,Liang; Chen,Keping.
Indica and japonica are two main subspecies of Asian cultivated rice (Oryza sativa L.) that differ clearly in morphological and agronomic traits, in physiological and biochemical characteristics and in their genomic structure. However, the proteins and genes responsible for these differences remain poorly characterized. In this study, proteomic tools, including two-dimensional electrophoresis and mass spectrometry, were used to globally identify proteins that differed between two sequenced rice varieties (93-11 and Nipponbare). In all, 47 proteins that differed significantly between 93-11 and Nipponbare were identified using mass spectrometry and database searches. Interestingly, seven proteins were expressed only in Nipponbare and one protein was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Indica and japonica rice; Molecular marker; Proteomics; Quantitative real-time PCR; Unique proteins.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000500008

Molecular cloning and expression of key gene encoding hypothetical DNA polymerase from B. mori parvo-like virus
Provedor de dados: 74
Autores: Zhang,Junhong; Li,Guohui; Chen,Huiqing; Li,Xiaogang; Lv,Meng; Chen,Keping; Yao,Qin.
BmPLV-Z is the abbreviation for Bombyx mori parvo-like virus (China isolate). This is a novel virus with two single-stranded linear DNA molecules, viz., VD1 (6543 bp) and VD2 (6022 bp), which are encapsidated respectively into separate virions. Analysis of the deduced amino acid sequence of VD1-ORF4 indicated the existence of a putative DNA-polymerase with exonuclease activity, possibly involved in the replication of BmPLV-Z. In the present study, a recombinant baculovirus was constructed to express the full length of the protein encoded by the VD1-ORF4 gene (3318 bp). In addition, a 2163-bp fragment amplified from the very same gene was cloned into prokaryotic expression vector pET-30a and expressed in E.coli Rosetta 2 (DE3) pLysS. The expressed fusion...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bombyx mori parvo-like virus; DNA polymerase; Recombinant protein; Sf-9.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000400021

Proteomic profiling of liver from Elaphe taeniura, a common snake in eastern and southeastern Asia
Provedor de dados: 74
Autores: Chen,Liang; Xia,Hengchuan; Wang,Yiting; Chen,Keping; Qin,Lvgao; Wang,Bin; Yao,Qin; Li,Jun; He,Yuanqing; Zhao,Ermi.
Snake liver has been implicated in the adaptation of snakes to a variety of habitats. However, to date, there has been no systematic analysis of snake liver proteins. In this study, we undertook a proteomic analysis of liver from the colubrid snake Elaphe taeniura using a combination of two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time of flightmass spectrometry (MALDI-TOF MS). We also constructed a local protein sequence database based on transcriptome sequencing to facilitate protein identification. Of the 268 protein spots revealed by 2-DE 109 gave positive MS signals, 84 of which were identified by searching the NCBInr, Swiss-Prot and local databases. The other 25 protein spots could not be identified, possibly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: 2D electrophoresis; Elaphe taeniura; MALDI-TOF mass spectrometry; Protein.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300020

Protein profile of rice (Oryza sativa) seeds
Provedor de dados: 74
Autores: Yang,Yanhua; Dai,Li; Xia,Hengchuan; Zhu,Keming; Liu,Haijun; Chen,Keping.
Seeds are the most important plant storage organ and play a central role in the life cycle of plants. Since little is known about the protein composition of rice (Oryza sativa) seeds, in this work we used proteomic methods to obtain a reference map of rice seed proteins and identify important molecules. Overall, 480 reproducible protein spots were detected by two-dimensional electrophoresis on pH 4-7 gels and 302 proteins were identified by MALDI-TOF MS and database searches. Together, these proteins represented 252 gene products and were classified into 12 functional categories, most of which were involved in metabolic pathways. Database searches combined with hydropathy plots and gene ontology analysis showed that most rice seed proteins were hydrophilic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mass spectrometry; Proteomic analysis; Rice seed; Two-dimensional electrophoresis.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000100012