• Title/Summary/Keyword: DNA mobility

Search Result 133, Processing Time 0.029 seconds

Identification and Functional Characterization of P159L Mutation in HNF1B in a Family with Maturity-Onset Diabetes of the Young 5 (MODY5)

  • Kim, Eun Ky;Lee, Ji Seon;Cheong, Hae Il;Chung, Sung Soo;Kwak, Soo Heon;Park, Kyong Soo
    • Genomics & Informatics
    • /
    • v.12 no.4
    • /
    • pp.240-246
    • /
    • 2014
  • Mutation in HNF1B, the hepatocyte nuclear factor-$1{\beta}$ (HNF-$1{\beta}$) gene, results in maturity-onset diabetes of the young (MODY) 5, which is characterized by gradual impairment of insulin secretion. However, the functional role of HNF-$1{\beta}$ in insulin secretion and glucose metabolism is not fully understood. We identified a family with early-onset diabetes that fulfilled the criteria of MODY. Sanger sequencing revealed that a heterozygous P159L (CCT to CTT in codon 159 in the DNA-binding domain) mutation in HNF1B was segregated according to the affected status. To investigate the functional consequences of this HNF1B mutation, we generated a P159L HNF1B construct. The wild-type and mutant HNF1B constructs were transfected into COS-7 cells in the presence of the promoter sequence of human glucose transporter type 2 (GLUT2). The luciferase reporter assay revealed that P159L HNF1B had decreased transcriptional activity compared to wild-type (p < 0.05). Electrophoretic mobility shift assay showed reduced DNA binding activity of P159L HNF1B. In the MIN6 pancreatic ${\beta}$-cell line, overexpression of the P159L mutant was significantly associated with decreased mRNA levels of GLUT2 compared to wild-type (p < 0.05). However, INS expression was not different between the wild-type and mutant HNF1B constructs. These findings suggests that the impaired insulin secretion in this family with the P159L HNF1B mutation may be related to altered GLUT2 expression in ${\beta}$-cells rather than decreased insulin gene expression. In conclusion, we have identified a Korean family with an HNF1B mutation and characterized its effect on the pathogenesis of diabetes.

Repression of CCSP Expression by KLF4 (KLF4에 의한 CCSP 발현 억제)

  • Kwak, Inseok
    • Journal of Life Science
    • /
    • v.28 no.12
    • /
    • pp.1432-1437
    • /
    • 2018
  • Clara cell secretory protein (CCSP) plays an important role in protecting the lungs from inflammation. This research focuses on identifying the cis-element for binding the repressor of CCSP gene expression. A DNase I footprinting experiment revealed three protected regions between -812 and -768 bp (45 bp) of the mCCSP promoter. One motif (D3: GCCTGGGAA) was 100% conserved across rat, hamster, and human. The addition of excess amounts of the D3 motif exhibited high competition within that 45 bp range in an electrophoretic mobility shift assay. However, when mutated D3 ($G{\underline{AA}}TG{\underline{TT}}AA$) was used, the competition was significantly reduced. This demonstrates that the D3 motif within that 45 bp region of the mCCSP promoter is an important site for the protein-DNA interaction. Transient transfection assays with -756 Luc resulted in highly decreased expression of CCSP than those with -812 Luc, suggesting that the 45 bp could function as a binding site for the repressor. Co-transfection of KLF4 exhibited significant repression of the -812 Luc but not the -768 Luc which clearly shows that KLF4 might function as a repressor for the CCSP gene and also suggests that the D3 motif is strongly involved in the binding of KLF4. In addition, when anti-KLF4 antibody was added, super-shifted bands were observed. This result demonstrates that KLF4 could function as a repressor by binding to this 45 bp region of the CCSP promoter and that the D3 motif might be involved in the specific binding of KLF4.

Inhibition of NF-IL6 Activity by Manassantin B, a Dilignan Isolated from Saururus chinensis, in Phorbol Myristate Acetate-stimulated U937 Promonocytic Cells

  • Son, Kyung-No;Song, In-Sung;Shin, Yong-Hyun;Pai, Tong-Kun;Chung, Dae-Kyun;Baek, Nam-In;Lee, Jung Joon;Kim, Jiyoung
    • Molecules and Cells
    • /
    • v.20 no.1
    • /
    • pp.105-111
    • /
    • 2005
  • Mannasantin B, a dilignan structurally related to manssantin A, is an inhibitor of NF-${\kappa}B$ transactivation. In the present study, we found that it inhibited PMA-induced expression of IL-$1{\beta}$, IL-$1{\beta}$ mRNA, and IL-$1{\beta}$ promoter activity in U937 cells with $IC_{50}$ values of about 50 nM. It also inhibited NF-IL6- and NF-${\kappa}B$-induced activation of IL-$1{\beta}$, with $IC_{50}$ values of 78 nM and $1.6{\mu}M$, respectively, revealing a potent inhibitory effect on NF-IL6. Electrophoretic mobility shift assays showed that manassantin B had an inhibitory effect on DNA binding by NF-IL6, but not by NF-${\kappa}B$. Further analysis revealed that transactivation by NF-IL6 was also inhibited. Our results indicate that manassantin B suppresses expression of IL-$1{\beta}$ in promonocytic cells by inhibiting not only NF-${\kappa}B$ but also NF-IL6 activity. Furthermore, our observations suggest that manassantin B may be clinically useful as a potent inhibitor of NF-IL6 activity.

Identification of specifically activated angiogenic molecules in HMGB-1-induced angiogenesis

  • Kim, Won Kyu;Kwon, Yujin;Park, Minhee;Yun, Seongju;Kwon, Ja-Young;Kim, Hoguen
    • BMB Reports
    • /
    • v.50 no.11
    • /
    • pp.590-595
    • /
    • 2017
  • High-mobility group box-1 (HMGB-1) is expressed in almost all cells, and its dysregulated expression correlates with inflammatory diseases, ischemia, and cancer. Some of these conditions accompany HMGB-1-mediated abnormal angiogenesis. Thus far, the mechanism of HMGB-1-induced angiogenesis remains largely unknown. In this study, we performed time-dependent DNA microarray analysis of endothelial cells (ECs) after HMGB-1 or VEGF treatment. The pathway analysis of each gene set upregulated by HMGB-1 or VEGF showed that most HMGB-1-induced angiogenic pathways were also activated by VEGF, although the activation time and gene sets belonging to the pathways differed. In addition, HMGB-1 upregulated some VEGFR signaling-related angiogenic factors including EGR1 and, importantly, novel angiogenic factors, such as ABL2, CEACAM1, KIT, and VIPR1, which are reported to independently promote angiogenesis under physiological and pathological conditions. Our findings suggest that HMGB-1 independently induces angiogenesis by activating HMGB-1-specific angiogenic factors and also functions as an accelerator for VEGF-mediated conventional angiogenesis.

Isolation and Characterization of Pathogen inducible Leucine Zipper containing Gene from rice (Oryza sativa L. cv. Dongjin)

  • Park, Sang-Ryeol;Song, Hae-Sook;Moon, Kyung-Mi;Hwang, Duk-Ju;Kim, Tae-Ho;Han, Seong-Sook;Go, Seung-Joo;Byun, Myung-Ok
    • Proceedings of the Korean Society of Plant Pathology Conference
    • /
    • 2003.10a
    • /
    • pp.83.2-83
    • /
    • 2003
  • A full length cDNA, OsLEUZIP, encoding leucine zipper containing protein from rice EST of rice (0ryza sativa L. cv. Dongjin) treated Xanthomonas oryzae pv. oryzae 10331. OsLEUZIP contains 1,227 bp nucleotides and encodes a protein of 408 amino acid residues with predicted molecular weight of 47,229 Da. The deduced amino acid sequence of OsLEUZIP has consensus sequence of leucine zipper from PROSITE (PDOC00029), L-X(6)-L-X(6)-L-X(6) -L. OsLEUZIP gene were preferentially induced in rice during incompatible interaction with Xanthomonas oryzae pv. oryzae 10331 and Pyracuraria grisea KJ-301. Expression of OsLEUZIP gene was also induced by treatment of abiotics such as ethephon and ABA. Our data represented in this study suggesting that OsLEUZIP gene may play an important role in the rice defense-related. Further studies of this gene, overexpression in rice, yeast-two hybrid assay, electrophoretic mobility shift assay and northern blot analyses of transgenic plant, would be useful to elucidate the role of the OsLEUZIP gene in defense responses of rice.

  • PDF

Role of CCAAT/ Enhancer Binding Protein ${\beta}$ Activation in the Induction of Glutathione S-Transferase A2 by Toluene

  • Choi, Dal-Woong;Sohn, Jong-Ryeul;Moon, Kyung-Whan;Byeon, Sang-Hoon;Kim, Hi-Chol;Kim, Young-Whan
    • Proceedings of the Korean Environmental Health Society Conference
    • /
    • 2005.06a
    • /
    • pp.341-344
    • /
    • 2005
  • The expression of the glutathione S-transferase (GST), whose induction accounts for antioxidant defense system, is regulated by activation of CCAAT/enhancer binding protein ${\beta}$ ($C/EBP{\beta}$), Sick house syndrome (SHS) presents healthy damage owing to the indoor environment of a building. Toluene has been implicated in one of the important causes of SHS. The present study investigated the effects of toluene treatment on the induction of GSTA2 gene and its mechanism. H411E cells treated with toluene, and GSTA2 expression was determined by immunoblot analysis. The translocation of $C/EBP{\beta}$ was assessed by immunocytochemical assays. $C/EBP{\beta}$ DNA binding activity was determined by electrophoretic mobility shift assays. The role of the C/EBP binding site in the induction of the GSTA2 gene was assessed by luciferase reporter-gene activity. Toluene induced GSTA2 protein expression. In toluene-treated cells, $C/EBP{\beta}$ translocated to the nucleus and bound to the consensus sequence of C/EBP (TTGCGCAA). Toluene treatment increased luciferase reporter-gene activity in cells transfected with the C/EBP-containing regulatory region of the GSTA2 gene. Oxidative stress is believed to play an important role in the induction of GSTA2 gene by toluene This study shows that toluene-induced GSTA2 gene expression is dependent upon nuclear translocation and binding of $C/EBP{\beta}$ to the C/EBP response element in the GSTA2 gene promoter.

  • PDF

Multiple Linkage Disequilibrium Mapping Methods to Validate Additive Quantitative Trait Loci in Korean Native Cattle (Hanwoo)

  • Li, Yi;Kim, Jong-Joo
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.28 no.7
    • /
    • pp.926-935
    • /
    • 2015
  • The efficiency of genome-wide association analysis (GWAS) depends on power of detection for quantitative trait loci (QTL) and precision for QTL mapping. In this study, three different strategies for GWAS were applied to detect QTL for carcass quality traits in the Korean cattle, Hanwoo; a linkage disequilibrium single locus regression method (LDRM), a combined linkage and linkage disequilibrium analysis (LDLA) and a $BayesC{\pi}$ approach. The phenotypes of 486 steers were collected for weaning weight (WWT), yearling weight (YWT), carcass weight (CWT), backfat thickness (BFT), longissimus dorsi muscle area, and marbling score (Marb). Also the genotype data for the steers and their sires were scored with the Illumina bovine 50K single nucleotide polymorphism (SNP) chips. For the two former GWAS methods, threshold values were set at false discovery rate <0.01 on a chromosome-wide level, while a cut-off threshold value was set in the latter model, such that the top five windows, each of which comprised 10 adjacent SNPs, were chosen with significant variation for the phenotype. Four major additive QTL from these three methods had high concordance found in 64.1 to 64.9Mb for Bos taurus autosome (BTA) 7 for WWT, 24.3 to 25.4Mb for BTA14 for CWT, 0.5 to 1.5Mb for BTA6 for BFT and 26.3 to 33.4Mb for BTA29 for BFT. Several candidate genes (i.e. glutamate receptor, ionotropic, ampa 1 [GRIA1], family with sequence similarity 110, member B [FAM110B], and thymocyte selection-associated high mobility group box [TOX]) may be identified close to these QTL. Our result suggests that the use of different linkage disequilibrium mapping approaches can provide more reliable chromosome regions to further pinpoint DNA makers or causative genes in these regions.

Magnolol Inhibits LPS-induced NF-${\kappa}B$/Rel Activation by Blocking p38 Kinase in Murine Macrophages

  • Li, Mei Hong;Kothandan, Gugan;Cho, Seung-Joo;Huong, Pham Thi Thu;Nan, Yong Hai;Lee, Kun-Yeong;Shin, Song-Yub;Yea, Sung-Su;Jeon, Young-Jin
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.14 no.6
    • /
    • pp.353-358
    • /
    • 2010
  • This study demonstrates the ability of magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, to inhibit LPS-induced expression of iNOS gene and activation of NF-${\kappa}B$/Rel in RAW 264.7 cells. Immunohisto-chemical staining of iNOS and Western blot analysis showed magnolol to inhibit iNOS gene expression. Reporter gene assay and electrophoretic mobility shift assay showed that magnolol inhibited NF-${\kappa}B$/Rel transcriptional activation and DNA binding, respectively. Since p38 is important in the regulation of iNOS gene expression, we investigated the possibility that magnolol to target p38 for its anti-inflammatory effects. A molecular modeling study proposed a binding position for magnolol that targets the ATP binding site of p38 kinase (3GC7). Direct interaction of magnolol and p38 was further confirmed by pull down assay using magnolol conjugated to Sepharose 4B beads. The specific p38 inhibitor SB203580 abrogated the LPS-induced NF-${\kappa}B$/Rel activation, whereas the selective MEK-1 inhibitor PD98059 did not affect the NF-${\kappa}B$/Rel. Collectively, the results of the series of experiments indicate that magnolol inhibits iNOS gene expression by blocking NF-${\kappa}B$/Rel and p38 kinase signaling.

Suppressive effects of Lithospermum erythrorhizon extracts on lipopolysaccharide-induced activation of AP-1 and NF-κB via mitogen-activated protein kinase pathways in mouse macrophage cells

  • Han, Kyu-Yeon;Kwon, Taek-Hwan;Lee, Tae-Hoon;Lee, Sung-Joon;Kim, Sung-Hoon;Kim, Ji-Young
    • BMB Reports
    • /
    • v.41 no.4
    • /
    • pp.328-333
    • /
    • 2008
  • A variety of anti-inflammatory agents have been shown to exert chemopreventive activity via targeting of transcription factors such as NF-${\kappa}B$ and AP-1. Lithospermum erythrorhizon (LE) has long been used in traditional oriental medicine. In this study, we demonstrated the inhibitory effects of LE extracts on lipopolysaccharide (LPS)-stimulated production of inflammatory cytokines. As an underlying mechanism of inhibition, LE extracts reduced LPS-induced transactivation of AP-1 as well as NF-${\kappa}B$ in mouse macrophage cells. Electrophoretic mobility shift assays indicated that LE extracts inhibited the DNA binding activities of AP-1 and NF-${\kappa}B$. In addition, phosphorylation of $I{\kappa}B-{\alpha}$ protein was suppressed by LE extracts. Moreover, LE extracts inhibited c-Jun N-terminal kinase and extracellular signal-regulated signaling pathways. Our results suggest that the anti-inflammatory activity of LE extracts may be mediated by the inhibition of signal transduction pathways that normally lead to the activation of AP-1and NF-${\kappa}B$. These inhibitory effects may be useful for chemoprevention of cancer or other chronic inflammatory diseases.

Zebrafish Dnd protein binds to 3'UTR of geminin mRNA and regulates its expression

  • Chen, Shu;Zeng, Mei;Sun, Huaqin;Deng, Wenqian;Lu, Yilu;Tao, Dachang;Liu, Yunqiang;Zhang, Sizhong;Ma, Yongxin
    • BMB Reports
    • /
    • v.43 no.6
    • /
    • pp.438-444
    • /
    • 2010
  • Dnd (dead end) gene encodes an RNA binding protein and is specifically expressed in primordial germ cells (PGCs) as a vertebrate-specific component of the germ plasma throughout embryogenesis. By utilizing a technique of specific nucleic acids associated with proteins (SNAAP), 13 potential target mRNAs of zebrafish Dnd (ZDnd) protein were identified from 8-cell embryo, and 8 target mRNAs have been confirmed using an RT-PCR analysis. Of the target mRNAs, the present study is focused on the regulation of geminin, which is an inhibitor of DNA replication. Using electrophoretic mobility shift assay (EMSA), we demonstrated that ZDND protein bound the 67-nucleotide region from 864 to 931 in the 3'UTR of geminin mRNA, a sequence containing 60.29% of uridine. Results from a dual-luciferase assay in HEK293 cells showed that ZDND increases the translation of geminin. Taken together, the identification of target mRNA for ZDnd will be helpful to further explore the biological function of Dnd in zebrafish germ-line development as well as in cancer cells.