1.Preparation of anti-hCG antibody-like molecule by using a RAD peptide display system.
Mengwen LIU ; Mei WANG ; Qiong WANG ; Huawei XIN
Chinese Journal of Biotechnology 2019;35(5):871-879
By using an RAD peptide display system derived from the ATPase domain of recombinase RadA of Pyrococcus furiosus, an anti-hCG antibody-like molecule was prepared by grafting an hCG-binding peptide to the RAD scaffold. After linking to sfGFP gene, a gene of hCG peptide-grafted RAD was synthesized and cloned into a bacterial expression vector (pET30a-RAD/hCGBP-sfGFP). The vector was transformed into Escherichia coli, and expression of the fusion protein was induced. After isolation and purification of the fusion protein, its binding affinity and specificity to hCG were determined by using a process of immunoabsorption followed by GFP fluorescence measurement. A comparison of hCG-binding activity with a similarly grafted single-domain antibody based on a universal scaffold was performed. The measurement of hCG-binding affinity and specificity revealed that the grafted RAD has an optimally high binding affinity and specificity to hCG, which are better than the grafted single-domain antibody. Moreover, the affinity and specificity of grafted RAD molecule are comparable to those of a commercial monoclonal antibody. In addition, the hCG-binding peptide-grafted RAD molecule has a relatively high biochemical stability, making it a good substitute for antibody with potential application.
Antibodies, Monoclonal
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chemistry
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isolation & purification
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metabolism
;
Antibody Specificity
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DNA-Binding Proteins
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genetics
;
metabolism
;
Escherichia coli
;
genetics
;
Escherichia coli Proteins
;
metabolism
;
Humans
;
Peptides
;
Recombinant Fusion Proteins
;
genetics
;
metabolism
2.Tet2 Regulates Osteoclast Differentiation by Interacting with Runx1 and Maintaining Genomic 5-Hydroxymethylcytosine (5hmC).
Yajing CHU ; Zhigang ZHAO ; David Wayne SANT ; Ganqian ZHU ; Sarah M GREENBLATT ; Lin LIU ; Jinhuan WANG ; Zeng CAO ; Jeanette Cheng THO ; Shi CHEN ; Xiaochen LIU ; Peng ZHANG ; Jaroslaw P MACIEJEWSKI ; Stephen NIMER ; Gaofeng WANG ; Weiping YUAN ; Feng-Chun YANG ; Mingjiang XU
Genomics, Proteomics & Bioinformatics 2018;16(3):172-186
As a dioxygenase, Ten-Eleven Translocation 2 (TET2) catalyzes subsequent steps of 5-methylcytosine (5mC) oxidation. TET2 plays a critical role in the self-renewal, proliferation, and differentiation of hematopoietic stem cells, but its impact on mature hematopoietic cells is not well-characterized. Here we show that Tet2 plays an essential role in osteoclastogenesis. Deletion of Tet2 impairs the differentiation of osteoclast precursor cells (macrophages) and their maturation into bone-resorbing osteoclasts in vitro. Furthermore, Tet2 mice exhibit mild osteopetrosis, accompanied by decreased number of osteoclasts in vivo. Tet2 loss in macrophages results in the altered expression of a set of genes implicated in osteoclast differentiation, such as Cebpa, Mafb, and Nfkbiz. Tet2 deletion also leads to a genome-wide alteration in the level of 5-hydroxymethylcytosine (5hmC) and altered expression of a specific subset of macrophage genes associated with osteoclast differentiation. Furthermore, Tet2 interacts with Runx1 and negatively modulates its transcriptional activity. Our studies demonstrate a novel molecular mechanism controlling osteoclast differentiation and function by Tet2, that is, through interactions with Runx1 and the maintenance of genomic 5hmC. Targeting Tet2 and its pathway could be a potential therapeutic strategy for the prevention and treatment of abnormal bone mass caused by the deregulation of osteoclast activities.
5-Methylcytosine
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analogs & derivatives
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chemistry
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metabolism
;
Animals
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Cell Differentiation
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Cells, Cultured
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Core Binding Factor Alpha 2 Subunit
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genetics
;
metabolism
;
DNA-Binding Proteins
;
physiology
;
Genome
;
Genomics
;
Mice
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Mice, Knockout
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Osteoclasts
;
cytology
;
metabolism
;
Proto-Oncogene Proteins
;
physiology
3.Relationship between Modulator Recognition Factor 2/AT-rich Interaction Domain 5B Gene Variations and Type 2 Diabetes Mellitus or Lipid Metabolism in a Northern Chinese Population.
Lu-Lu SUN ; Si-Jia ZHANG ; Mei-Jun CHEN ; Kazakova ELENA ; Hong QIAO
Chinese Medical Journal 2017;130(9):1055-1061
BACKGROUNDFour single nucleotide polymorphisms (SNPs) in the modulator recognition factor 2/AT-rich interaction domain 5B (MRF2/ARID5B) gene located at chromosome 10q21.2 have been shown to be associated with both type 2 diabetes mellitus (T2DM) and coronary artery disease in a Japanese cohort. This study aimed to investigate the relationship between these SNPs (rs2893880, rs10740055, rs7087507, rs10761600) and new-onset T2DM and lipid metabolism in a Northern Chinese population.
METHODSThis was a case-control study. The rs2893880, rs10740055, rs7087507, and rs10761600 genetic variants were genotyped by SNPscan and analyzed in relation to T2DM susceptibility in 2000 individuals (999 with newly diagnosed T2DM and 1001 controls without diabetes mellitus). Associations between the MRF2/ARID5B genetic models and T2DM were determined by multivariate logistic regression.
RESULTSRegarding the rs10740055 SNP, AA was associated with a higher risk of T2DM compared with codominant-type CC (adjusted by sex, age, and body mass index [BMI], P= 0.041, odds ratio [OR] = 1.421, 95% confidence interval [CI] 1.014-1.991). Meanwhile, AA individuals were at increased risk of presenting with T2DM compared with individuals with CC or a single C (adjusted by sex, age, and BMI, P= 0.034, OR = 1.366, 95% CI 1.023-1.824). With respect to rs10761600, AT contributed to a higher risk of T2DM compared with AA (adjusted by sex, age, and BMI, P= 0.013, OR = 1.585, 95% CI 1.101-2.282), while TT also increased the risk of presenting with T2DM compared with AA or A (adjusted by sex, age, and BMI, P= 0.004, OR = 1.632, 95% CI 1.166-2.284). High-density lipoprotein cholesterol (HDL-C) levels were significantly different among the three genotypes of rs7087507 in the controls (P = 0.048) (GG>GA).
CONCLUSIONSThe present results identified MRF2/ARID5B as a potential susceptibility gene for new-onset T2DM in a Northern Chinese population, while the rs7087507 SNP was associated with HDL-C levels. Further larger studies are required to validate these findings.
Asian Continental Ancestry Group ; Case-Control Studies ; DNA-Binding Proteins ; chemistry ; genetics ; metabolism ; Diabetes Mellitus, Type 2 ; genetics ; metabolism ; Genetic Association Studies ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Lipid Metabolism ; genetics ; physiology ; Odds Ratio ; Polymorphism, Single Nucleotide ; genetics ; Transcription Factors ; chemistry ; genetics ; metabolism
4.Adeno-Associated Virus 2-Mediated Hepatocellular Carcinoma is Very Rare in Korean Patients.
Kyoung Jin PARK ; Jongan LEE ; June Hee PARK ; Jae Won JOH ; Choon Hyuck David KWON ; Jong Won KIM
Annals of Laboratory Medicine 2016;36(5):469-474
BACKGROUND: The incidence and etiology of hepatocellular carcinoma (HCC) vary widely according to race and geographic regions. The insertional mutagenesis of adeno-associated virus 2 (AAV2) has recently been considered a new viral etiology of HCC. The aim of this study was to investigate the frequency and clinical characteristics of AAV2 in Korean patients with HCC. METHODS: A total of 289 unrelated Korean patients with HCC, including 159 Hepatitis-B-related cases, 16 Hepatitis-C-related cases, and 114 viral serology-negative cases, who underwent surgery at the Samsung Medical Center in Korea from 2009 to 2014 were enrolled in this study. The presence of AAV2 in fresh-frozen tumor tissues was investigated by DNA PCR and Sanger sequencing. The clinical and pathological characteristics of AAV2-associated HCC in these patients were compared with previous findings in French patients. RESULTS: The AAV2 detection rate in Korean patients (2/289) was very low compared with that in French patients (11/193). Similar to the French patients, the Korean patients with AAV2-related HCC showed no signs of liver cirrhosis. The Korean patients were younger than the French patients with the same AAV2-associated HCC; the ages at diagnosis of the two Korean patients were 47 and 39 yr, while the median age of the 11 French patients was 55 yr (range 43-90 yr). CONCLUSIONS: AAV2-associated HCC was very rare in Korean patients with HCC. Despite a limited number of cases, this study is the first to report the clinical characteristics of Korean patients with AAV2-associated HCC. These findings suggest epidemiologic differences in viral hepatocarcinogenesis between Korean and European patients.
Adult
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Asian Continental Ancestry Group
;
Capsid Proteins/genetics
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Carcinoma, Hepatocellular/etiology/*pathology/virology
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DNA, Viral/chemistry/genetics/metabolism
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DNA-Binding Proteins/genetics
;
Dependovirus/*genetics/isolation & purification/pathogenicity
;
Female
;
Humans
;
Incidence
;
Inverted Repeat Sequences/genetics
;
Liver Neoplasms/etiology/*pathology/virology
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Male
;
Middle Aged
;
Parvoviridae Infections/complications/epidemiology
;
Polymerase Chain Reaction
;
Republic of Korea
;
Sequence Analysis, DNA
;
Viral Proteins/genetics
5.Non-Homologous End Joining Repair Mechanism-Mediated Deletion of CHD7 Gene in a Patient with Typical CHARGE Syndrome.
Seung Jun LEE ; Jong Hee CHAE ; Jung Ae LEE ; Sung Im CHO ; Soo Hyun SEO ; Hyunwoong PARK ; Moon Woo SEONG ; Sung Sup PARK
Annals of Laboratory Medicine 2015;35(1):141-145
CHARGE syndrome MIM #214800 is an autosomal dominant syndrome involving multiple congenital malformations. Clinical symptoms include coloboma, heart defects, choanal atresia, retardation of growth or development, genital hypoplasia, and ear anomalies or deafness. Mutations in the chromodomain helicase DNA binding protein 7 (CHD7) gene have been found in 65-70% of CHARGE syndrome patients. Here, we describe a 16-month-old boy with typical CHARGE syndrome, who was referred for CHD7 gene analysis. Sequence analysis and multiplex ligation-dependent probe amplification were performed. A heterozygous 38,304-bp deletion encompassing exon 3 with a 4-bp insertion was identified. There were no Alu sequences adjacent to the breakpoints, and no sequence microhomology was observed at the junction. Therefore, this large deletion may have been mediated by non-homologous end joining. The mechanism of the deletion in the current case differs from the previously suggested mechanisms underlying large deletions or complex genomic rearrangements in the CHD7 gene, and this is the first report of CHD7 deletion by this mechanism worldwide.
Alu Elements/genetics
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Base Sequence
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CHARGE Syndrome/diagnosis/*genetics
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DNA/chemistry/metabolism
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*DNA End-Joining Repair
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DNA Helicases/*genetics/metabolism
;
DNA-Binding Proteins/*genetics/metabolism
;
Exons
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Gene Dosage
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Heterozygote
;
Humans
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Infant
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Male
;
Multiplex Polymerase Chain Reaction
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Mutation
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Sequence Analysis, DNA
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*Sequence Deletion
6.Binding of human SWI1 ARID domain to DNA without sequence specificity: A molecular dynamics study.
Qian SUN ; Tao ZHU ; Chang-Yu WANG ; Ding MA
Journal of Huazhong University of Science and Technology (Medical Sciences) 2015;35(4):469-476
SWI1 is a member of a new class of tumor DNA-binding proteins named as the AT-rich interaction domain family (ARID), and considered to bind with AT base pairs specifically. Genomic and functional data support ARID1A as a tumor suppressor because ARID1A/BAF250a (SWI1) subunit of the SWI/SNF chromatin-remodeling complex has emerged as recurrently mutated in a broad array of tumor types. But the crystal structure of SWI1 has not been solved as yet. Using docking and molecular dynamics, we predicted the DNA interaction pattern of human SWI1 ARID and made comparisons with the other two representative ARID family members, human Mrf-2 ARID and Drosophila Dri ARID. Dynamic results revealed that the N-terminal and loop L1 of SWI1 ARID bound with the DNA major groove, while the loop L2 and helix H6 bound with the minor groove. Moreover, it was found that SWI1 ARID bound with DNA apparently in a sequence-nonspecific manner. It was concluded that SWI1 ARID can form stable complex with sequence-nonspecific DNA segment comparing to Mrf-2 ARID/DNA and Dri ARID/DNA sequence-specific complexes.
Binding Sites
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DNA
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chemistry
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metabolism
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DNA-Binding Proteins
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chemistry
;
metabolism
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Drosophila Proteins
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chemistry
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Homeodomain Proteins
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chemistry
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Humans
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Models, Molecular
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Molecular Docking Simulation
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Molecular Dynamics Simulation
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Nuclear Proteins
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chemistry
;
Protein Structure, Tertiary
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Transcription Factors
;
chemistry
;
metabolism
7.Binding of Shewanella FadR to the fabA fatty acid biosynthetic gene: implications for contraction of the fad regulon.
Huimin ZHANG ; Beiwen ZHENG ; Rongsui GAO ; Youjun FENG
Protein & Cell 2015;6(9):667-679
The Escherichia coli fadR protein product, a paradigm/prototypical FadR regulator, positively regulates fabA and fabB, the two critical genes for unsaturated fatty acid (UFA) biosynthesis. However the scenario in the other Ɣ-proteobacteria, such as Shewanella with the marine origin, is unusual in that Rodionov and coworkers predicted that only fabA (not fabB) has a binding site for FadR protein. It raised the possibility of fad regulon contraction. Here we report that this is the case. Sequence alignment of the FadR homologs revealed that the N-terminal DNA-binding domain exhibited remarkable similarity, whereas the ligand-accepting motif at C-terminus is relatively-less conserved. The FadR homologue of S. oneidensis (referred to FadR_she) was over-expressed and purified to homogeneity. Integrative evidence obtained by FPLC (fast protein liquid chromatography) and chemical cross-linking analyses elucidated that FadR_she protein can dimerize in solution, whose identity was determined by MALDI-TOF-MS. In vitro data from electrophoretic mobility shift assays suggested that FadR_she is almost functionally-exchangeable/equivalent to E. coli FadR (FadR_ec) in the ability of binding the E. coli fabA (and fabB) promoters. In an agreement with that of E. coli fabA, S. oneidensis fabA promoter bound both FadR_she and FadR_ec, and was disassociated specifically with the FadR regulatory protein upon the addition of long-chain acyl-CoA thioesters. To monitor in vivo effect exerted by FadR on Shewanella fabA expression, the native promoter of S. oneidensis fabA was fused to a LacZ reporter gene to engineer a chromosome fabA-lacZ transcriptional fusion in E. coli. As anticipated, the removal of fadR gene gave about 2-fold decrement of Shewanella fabA expression by β-gal activity, which is almost identical to the inhibitory level by the addition of oleate. Therefore, we concluded that fabA is contracted to be the only one member of fad regulon in the context of fatty acid synthesis in the marine bacteria Shewanella genus.
Amino Acid Sequence
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Bacterial Proteins
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chemistry
;
metabolism
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Base Sequence
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Binding Sites
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DNA, Bacterial
;
metabolism
;
Escherichia coli
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genetics
;
metabolism
;
Fatty Acid Synthase, Type II
;
genetics
;
metabolism
;
Fatty Acids
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biosynthesis
;
Gene Expression Regulation, Bacterial
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drug effects
;
Molecular Sequence Data
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Oleic Acid
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pharmacology
;
Protein Binding
;
drug effects
;
Regulon
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genetics
;
Repressor Proteins
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chemistry
;
metabolism
;
Shewanella
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genetics
;
metabolism
8.Correlation of Ciprofloxacin Resistance with the AdeABC Efflux System in Acinetobacter baumannii Clinical Isolates.
Abdollah ARDEBILI ; Abdolaziz Rastegar LARI ; Malihe TALEBI
Annals of Laboratory Medicine 2014;34(6):433-438
BACKGROUND: Acinetobacter baumannii is one of the most important pathogens capable of colonization in burn patients, leading to drug-resistant wound infections. This study evaluated the distribution of the AdeABC efflux system genes and their relationship to ciprofloxacin resistance in A. baumannii isolates collected from burn patients. METHODS: A total of 68 A. baumannii clinical strains were isolated from patients hospitalized in Motahari Burns Center in Tehran, Iran. Ciprofloxacin susceptibility was tested by the disk diffusion and agar dilution methods. PCR amplification of the adeRS-adeB drug efflux genes was performed for all resistant and susceptible isolates. To assess the role of the drug efflux pump in ciprofloxacin susceptibility, carbonyl cyanide 3-chlorophenylhydrazone (CCCP) was used as an efflux pump inhibitor (EPI). RESULTS: Approximately 95.6% of the Acinetobacter isolates were resistant to ciprofloxacin, with minimum inhibitory concentration (MIC) values ranging from 4 to > or =128 microg/mL. The susceptibility of 86.1% of the resistant isolates increased by factors of 2 to 64 in the presence of CCCP. All resistant isolates were positive for the adeRS-adeB genes, and 73.2% of them had mutations in the AdeRS regulatory system. CONCLUSIONS: The results showed that AdeABC genes are common in A. baumannii, which might be associated with ciprofloxacin non-susceptibility, as indicated by the observed linkage to the presence of the genes essential for the activity of the AdeABC, several single mutations occurring in the adeRS regulatory system, and an increase of ciprofloxacin susceptibility in the presence of a CCCP EPI.
ATP-Binding Cassette Transporters/antagonists & inhibitors/genetics/*metabolism
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Acinetobacter Infections/diagnosis/microbiology
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Acinetobacter baumannii/*drug effects/genetics/isolation & purification
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Anti-Bacterial Agents/*pharmacology
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Bacterial Proteins/antagonists & inhibitors/genetics/*metabolism
;
Base Sequence
;
Ciprofloxacin/*pharmacology
;
DNA, Bacterial/chemistry/genetics/metabolism
;
Drug Resistance, Bacterial
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Humans
;
Hydrazones/pharmacology
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Microbial Sensitivity Tests
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Mutation
;
Polymerase Chain Reaction
9.Expression of nesfatin-1/NUCB2 and ghrelin in gastric mucosa of rats with intrauterine growth retardation.
Ya-Ying CHENG ; Hong-Yan LV ; Xin WANG ; Guang-Yao SONG
Chinese Journal of Contemporary Pediatrics 2014;16(10):1051-1056
OBJECTIVETo investigate the expression of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats with intrauterine growth retardation (IUGR) and its significance.
METHODSThe IUGR animal model was established by feeding rats low-protein diets during their pregnancy. Newborn rats were divided into catch-up growth, non-catch-up growth and control groups. Protein and mRNA levels of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats were determined by RT-PCR and Western blot, respectively.
RESULTSNesfatin-1/NUCB2 mRNA and protein were expressed in the gastric mucosa of rats immediately after birth, and their expression increased in an age-dependent manner in all three groups. Furthermore, the level of nesfatin-1/NUCB2 in the catch-up growth group was higher than that in the control group before weaning, whereas there was no significant difference in nesfatin-1/NUCB2 expression between the two groups after weaning. The level of nesfatin-1/NUCB2 in the non-catch-up growth group was lower than that in the catch-up growth group during the whole observation period. The level of ghrelin in the catch-up growth group was higher than that in the control group starting from day 12 after birth, whereas there was no significant difference in ghrelin expression between the two groups after weaning. The level of ghrelin in the non-catch-up growth group was lower compared with those in the catch-up growth and control groups from days 12 to 28 after birth.
CONCLUSIONSNesfatin-1 and ghrelin are co-expressed in the gastric mucosa of rats with IUGR after birth and interact with each other to produce long-term nutritional regulation.
Age Factors ; Animals ; Calcium-Binding Proteins ; analysis ; genetics ; DNA-Binding Proteins ; analysis ; genetics ; Female ; Fetal Growth Retardation ; metabolism ; Gastric Mucosa ; chemistry ; Ghrelin ; analysis ; genetics ; Male ; Nerve Tissue Proteins ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley
10.Optimization of expression and purification of recombinant Salvia miltiorrhiza WRKY1 protein in Escherichia coli.
Yu-Zhong LIU ; Ye SHEN ; Qi-Xian RONG ; Wen-Yan WU ; Rui-Bo LI ; Zhi-Gang WU ; Min CHEN
China Journal of Chinese Materia Medica 2014;39(7):1214-1219
WRKY transcription factor is one of the Zinc finger proteins which contains a highly conserved WRKY domain and is a family of the plant-specific transcription factor. The plasmid pET28a-SmWRKY1 harboring Salvia miltiorrhiza WRKY1 (SmWRKY1) gene was successfully transformed and expressed in Escherichia coli BL21 (DE3). The conditions on protein expression of SmWRKY1 in E. coli, including induction duration, temperature, IPTG concentration and the E. coli concentration were optimized. The results showed that the highest protein expression of SmWRKY1 was obtained at 24 hours after the E. coli was cultured in the presence of 0.2 mol x L(-1) IPTG at 20 degrees C with A600 values of 1.0-1.5. This recombinant histidine-tagged protein was expressed at 2.454 g x L(-1) as inclusion body, which was first extracted using urea, and then purified by Ni2+ affinity chromatography and identified by SDS-PAGE. The expression of SmWRKY1 in E. coli was further confirmed by western blotting analysis.
Blotting, Western
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Cloning, Molecular
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DNA-Binding Proteins
;
chemistry
;
genetics
;
isolation & purification
;
metabolism
;
Electrophoresis, Polyacrylamide Gel
;
Escherichia coli
;
chemistry
;
genetics
;
metabolism
;
Molecular Weight
;
Plant Proteins
;
chemistry
;
genetics
;
isolation & purification
;
metabolism
;
Recombinant Proteins
;
chemistry
;
genetics
;
isolation & purification
;
metabolism
;
Salvia miltiorrhiza
;
genetics

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