Displaying publications 81 - 100 of 170 in total

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  1. The functional -94 insertion/deletion ATTG polymorphism in the promoter region of NFKB1 gene increases the risk of sporadic colorectal cancer
    Mohd Suzairi MS, Tan SC, Ahmad Aizat AA, Mohd Aminudin M, Siti Nurfatimah MS, Andee ZD, et al.
    Cancer Epidemiol, 2013 Oct;37(5):634-8.
    PMID: 23806437 DOI: 10.1016/j.canep.2013.05.007
    To investigate the allele and genotype frequencies of NFKB1 -94 ins/del ATTG (rs28720239) polymorphism and to evaluate the association between the polymorphism and colorectal cancer (CRC) risk in Malaysian population.
    Matched MeSH terms: Promoter Regions, Genetic
  2. Transcriptional regulation of retinol binding protein 4 by Interleukin-6 via peroxisome proliferator-activated receptor α and CCAAT/Enhancer binding proteins
    Mohd MA, Ahmad Norudin NA, Muhammad TST
    Mol Cell Endocrinol, 2020 04 05;505:110702.
    PMID: 31927097 DOI: 10.1016/j.mce.2020.110702
    Interleukin-6 (IL-6) is a major mediator of the acute phase response (APR) that regulates the transcription of acute phase proteins (APPs) in the liver. During APR, the plasma levels of negative APPs including retinol binding protein 4 (RBP4) are reduced. Activation of the IL-6 receptor and subsequent signaling pathways leads to the activation of transcription factors, including peroxisome proliferator-activated receptor alpha (PPARα) and CCAAT/enhancer binding protein (C/EBP), which then modulate APP gene expression. The transcriptional regulation of RBP4 by IL-6 is not fully understood. Therefore, this study aimed to elucidate the molecular mechanisms of PPARα and C/EBP isoforms in mediating IL-6 regulation of RBP4 gene expression. IL-6 was shown to reduce the transcriptional activity of RBP4, and functional dissection of the RBP4 promoter further identified the cis-acting regulatory elements that are responsible in mediating the inhibitory effect of IL-6. The binding sites for PPARα and C/EBP present in the RBP4 promoter were predicted at -1079 bp to -1057 bp and -1460 bp to -1439 bp, respectively. The binding of PPARα and C/EBPs to their respective cis-acting elements may lead to antagonistic interactions that modulate the IL-6 regulation of RBP4 promoter activity. Therefore, this study proposed a new mechanism of interaction involving PPARα and different C/EBP isoforms. This interaction is necessary for the regulation of RBP4 gene expression in response to external stimuli, particularly IL-6, during physiological changes.
    Matched MeSH terms: Promoter Regions, Genetic
  3. Spectrum of germ-line RB1 gene mutations in Malaysian patients with retinoblastoma
    Mohd Khalid MK, Yakob Y, Md Yasin R, Wee Teik K, Siew CG, Rahmat J, et al.
    Mol Vis, 2015;21:1185-90.
    PMID: 26539030
    The availability of molecular genetic testing for retinoblastoma (RB) in Malaysia has enabled patients with a heritable predisposition to the disease to be identified, which thus improves the clinical management of these patients and their families. In this paper, we presented our strategy for performing molecular genetic testing of the RB1 gene and the findings from our first 2 years of starting this service.
    Matched MeSH terms: Promoter Regions, Genetic
  4. Fulltext DNA Methylation of Human Choline Kinase Alpha Promoter-Associated CpG Islands in MCF-7 Cells
    Mohamed Sa'dom SAF, Raikundalia S, Shamsuddin S, See Too WC, Few LL
    Genes (Basel), 2021 06 01;12(6).
    PMID: 34205960 DOI: 10.3390/genes12060853
    Choline kinase (CK) is the enzyme catalyzing the first reaction in CDP-choline pathway for the biosynthesis of phosphatidylcholine. Higher expression of the α isozyme of CK has been implicated in carcinogenesis, and inhibition or downregulation of CKα (CHKA) is a promising anticancer approach. This study aimed to investigate the regulation of CKα expression by DNA methylation of the CpG islands found on the promoter of this gene in MCF-7 cells. Four CpG islands have been predicted in the 2000 bp promoter region of ckα (chka) gene. Six CpG island deletion mutants were constructed using PCR site-directed mutagenesis method and cloned into pGL4.10 vectors for promoter activity assays. Deletion of CpG4C region located between -225 and -56 significantly increased the promoter activity by 4-fold, indicating the presence of important repressive transcription factor binding site. The promoter activity of methylated full-length promoter was significantly lower than the methylated CpG4C deletion mutant by 16-fold. The results show that DNA methylation of CpG4C promotes the binding of the transcription factor that suppresses the promoter activity. Electrophoretic mobility shift assay analysis showed that cytosine methylation at MZF1 binding site in CpG4C increased the binding of putative MZF1 in nuclear extract. In conclusion, the results suggest that DNA methylation decreased the promoter activity by promoting the binding of putative MZF1 transcription factor at CpG4C region of the ckα gene promoter.
    Matched MeSH terms: Promoter Regions, Genetic
  5. Fulltext Aberrant Methylation of Tumour Suppressor Gene ADAM12 in Chronic Lympocytic Leukemia Patients: Application of Methylation Specific-PCR Technique
    Mohamad A, Hassan R, Husin A, Johan MF, Sulong S
    Asian Pac J Cancer Prev, 2021 Jan 01;22(1):85-91.
    PMID: 33507683 DOI: 10.31557/APJCP.2021.22.1.85
    OBJECTIVE: Chronic Lymphocytic Leukemia (CLL) is a common leukemia among Caucasians but rare in Asians population. We postulated that aberrant methylation either hypermethylation or partial methylation might be one of the silencing mechanisms that inactivates the tumour suppressor genes in CLL. This study aimed to compare the methylation status of tumour suppressor gene, ADAM12, among CLL patients and normal individuals. We also evaluated the association between methylation of ADAM12 and clinical and demographic characteristics of the participants.

    METHODS: A total of 25 CLL patients and 25 normal individuals were recruited in this study. The methylation status of ADAM12 was determined using Methylation-Specific PCR (MSP); whereas, DNA sequencing method was applied for validation of the MSP results.

    RESULTS: Among CLL patients, 12 (48%) were partially methylated and 13 (52%) were unmethylated. Meanwhile, 5 (20%) and 20 (80.6%) of healthy individuals were partially methylated and unmethylated, respectively. There was a statistically significant association between the status of methylation at ADAM12 and the presence of CLL (p=0.037).

    CONCLUSION: The aberrant methylation of ADAM12 found in this study using MSP assay may provide new exposure to CLL that may improve the gaps involved in genetic epigenetic study in CLL.

    Matched MeSH terms: Promoter Regions, Genetic
  6. Exploring breast carcinogenesis through integrative genomics and epigenomics analyses
    Minning C, Mokhtar NM, Abdullah N, Muhammad R, Emran NA, Ali SA, et al.
    Int J Oncol, 2014 Nov;45(5):1959-68.
    PMID: 25175708 DOI: 10.3892/ijo.2014.2625
    There have been many DNA methylation studies on breast cancer which showed various methylation patterns involving tumour suppressor genes and oncogenes but only a few of those studies link the methylation data with gene expression. More data are required especially from the Asian region and to analyse how the epigenome data correlate with the transcriptome. DNA methylation profiling was carried out on 76 fresh frozen primary breast tumour tissues and 25 adjacent non-cancerous breast tissues using the Illumina Infinium(®) HumanMethylation27 BeadChip. Validation of methylation results was performed on 7 genes using either MS-MLPA or MS-qPCR. Gene expression profiling was done on 15 breast tumours and 5 adjacent non-cancerous breast tissues using the Affymetrix GeneChip(®) Human Gene 1.0 ST array. The overlapping genes between DNA methylation and gene expression datasets were further mapped to the KEGG database to identify the molecular pathways that linked these genes together. Supervised hierarchical cluster analysis revealed 1,389 hypermethylated CpG sites and 22 hypomethylated CpG sites in cancer compared to the normal samples. Gene expression microarray analysis using a fold-change of at least 1.5 and a false discovery rate (FDR) at p>0.05 identified 404 upregulated and 463 downregulated genes in cancer samples. Integration of both datasets identified 51 genes with hypermethylation with low expression (negative association) and 13 genes with hypermethylation with high expression (positive association). Most of the overlapping genes belong to the focal adhesion and extracellular matrix-receptor interaction that play important roles in breast carcinogenesis. The present study displayed the value of using multiple datasets in the same set of tissues and how the integrative analysis can create a list of well-focused genes as well as to show the correlation between epigenetic changes and gene expression. These gene signatures can help us understand the epigenetic regulation of gene expression and could be potential targets for therapeutic intervention in the future.
    Matched MeSH terms: Promoter Regions, Genetic
  7. Isolation and characterization of oil palm constitutive promoter derived from ubiquitin extension protein (uep1) gene
    Masura SS, Parveez GK, Ismail I
    N Biotechnol, 2010 Sep 30;27(4):289-99.
    PMID: 20123048 DOI: 10.1016/j.nbt.2010.01.337
    The ubiquitin extension protein (uep1) gene was identified as a constitutively expressed gene in oil palm. We have isolated and characterized the 5' region of the oil palm uep1 gene, which contains an 828 bp sequence upstream of the uep1 translational start site. Construction of a pUEP1 transformation vector, which contains gusA reporter gene under the control of uep1 promoter, was carried out for functional analysis of the promoter through transient expression studies. It was found that the 5' region of uep1 functions as a constitutive promoter in oil palm and could drive GUS expression in all tissues tested, including embryogenic calli, embryoid, immature embryo, young leaflet from mature palm, green leaf, mesocarp and meristematic tissues (shoot tip). This promoter could also be used in dicot systems as it was demonstrated to be capable of driving gusA gene expression in tobacco.
    Matched MeSH terms: Promoter Regions, Genetic*
  8. Isolation and characterization of an oil palm constitutive promoter derived from a translationally control tumor protein (TCTP) gene
    Masura SS, Parveez GK, Ti LL
    Plant Physiol Biochem, 2011 Jul;49(7):701-8.
    PMID: 21549610 DOI: 10.1016/j.plaphy.2011.04.003
    We have characterized an oil palm (Elaeis guineensis Jacq.) constitutive promoter that is derived from a translationally control tumor protein (TCTP) gene. The TCTP promoter was fused transcriptionally with the gusA reporter gene and transferred to monocot and dicot systems in order to study its regulatory role in a transient expression study. It was found that the 5' region of TCTP was capable of driving the gusA expression in all the oil palm tissues tested, including immature embryo, embryogenic callus, embryoid, young leaflet from mature palm, green leaf, mesocarp and stem. It could also be used in dicot systems as it was also capable of driving gusA expression in tobacco leaves. The results indicate that the TCTP promoter could be used for the production of recombinant proteins that require constitutive expression in the plant system.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  9. Fulltext Analysis of Comparative Sequence and Genomic Data to Verify Phylogenetic Relationship and Explore a New Subfamily of Bacterial Lipases
    Masomian M, Rahman RN, Salleh AB, Basri M
    PLoS One, 2016;11(3):e0149851.
    PMID: 26934700 DOI: 10.1371/journal.pone.0149851
    Thermostable and organic solvent-tolerant enzymes have significant potential in a wide range of synthetic reactions in industry due to their inherent stability at high temperatures and their ability to endure harsh organic solvents. In this study, a novel gene encoding a true lipase was isolated by construction of a genomic DNA library of thermophilic Aneurinibacillus thermoaerophilus strain HZ into Escherichia coli plasmid vector. Sequence analysis revealed that HZ lipase had 62% identity to putative lipase from Bacillus pseudomycoides. The closely characterized lipases to the HZ lipase gene are from thermostable Bacillus and Geobacillus lipases belonging to the subfamily I.5 with ≤ 57% identity. The amino acid sequence analysis of HZ lipase determined a conserved pentapeptide containing the active serine, GHSMG and a Ca(2+)-binding motif, GCYGSD in the enzyme. Protein structure modeling showed that HZ lipase consisted of an α/β hydrolase fold and a lid domain. Protein sequence alignment, conserved regions analysis, clustal distance matrix and amino acid composition illustrated differences between HZ lipase and other thermostable lipases. Phylogenetic analysis revealed that this lipase represented a new subfamily of family I of bacterial true lipases, classified as family I.9. The HZ lipase was expressed under promoter Plac using IPTG and was characterized. The recombinant enzyme showed optimal activity at 65 °C and retained ≥ 97% activity after incubation at 50 °C for 1h. The HZ lipase was stable in various polar and non-polar organic solvents.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  10. Construction of PHB and PHBV multiple-gene vectors driven by an oil palm leaf-specific promoter
    Masani MY, Parveez GK, Izawati AM, Lan CP, Siti Nor Akmar A
    Plasmid, 2009 Nov;62(3):191-200.
    PMID: 19699761 DOI: 10.1016/j.plasmid.2009.08.002
    One of the targets in oil palm genetic engineering programme is the production of polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-valerate (PHBV) in the oil palm leaf tissues. Production of PHB requires the use of phbA (beta-ketothiolase type A), phbB (acetoacetyl-CoA reductase) and phbC (PHB synthase) genes of Ralstonia eutropha, whereas bktB (beta-ketothiolase type B), phbB, phbC genes of R. eutropha and tdcB (threonine dehydratase) gene of Escherichia coli were used for PHBV production. Each of these genes was fused with a transit peptide (Tp) of oil palm acyl-carrier-protein (ACP) gene, driven by an oil palm leaf-specific promoter (LSP1) to genetically engineer the PHB/PHBV pathway to the plastids of the leaf tissues. In total, four transformation vectors, designated pLSP15 (PHB) and pLSP20 (PHBV), and pLSP13 (PHB) and pLSP23 (PHBV), were constructed for transformation in Arabidopsis thaliana and oil palm, respectively. The phosphinothricin acetyltransferase gene (bar) driven by CaMV35S promoter in pLSP15 and pLSP20, and ubiquitin promoter in pLSP13 and pLSP23 were used as the plant selectable markers. Matrix attachment region of tobacco (RB7MAR) was also included in the vectors to stabilize the transgene expression and to minimize silencing due to positional effect. Restriction digestion, PCR amplification and/or sequencing were carried out to ensure sequence integrity and orientation.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  11. Construction of a novel inducible expression vector for Lactococcus lactis M4 and Lactobacillus plantarum Pa21
    Maidin MS, Song AA, Jalilsood T, Sieo CC, Yusoff K, Rahim RA
    Plasmid, 2014 Jul;74:32-8.
    PMID: 24879963 DOI: 10.1016/j.plasmid.2014.05.003
    A vector that drives the expression of the reporter gusA gene in both Lactobacillus plantarum and Lactococcus lactis was constructed in this study. This vector contained a newly characterized heat shock promoter (Phsp), amplified from an Enterococcus faecium plasmid, pAR6. Functionality and characterization of this promoter was initially performed by cloning Phsp into pNZ8008, a commercial lactococcal plasmid used for screening of putative promoters which utilizes gusA as a reporter. It was observed that Phsp was induced under heat, salinity and alkaline stresses or a combination of all three stresses. The newly characterized Phsp promoter was then used to construct a novel Lactobacillus vector, pAR1801 and its ability to express the gusA under stress-induced conditions was reproducible in both Lb. plantarum Pa21 and L. lactis M4 hosts.
    Matched MeSH terms: Promoter Regions, Genetic
  12. Expression of rice thaumatin-like protein gene in transgenic banana plants enhances resistance to fusarium wilt
    Mahdavi F, Sariah M, Maziah M
    Appl Biochem Biotechnol, 2012 Feb;166(4):1008-19.
    PMID: 22183565 DOI: 10.1007/s12010-011-9489-3
    The possibility of controlling Fusarium wilt--caused by Fusarium oxysporum sp. cubensec (race 4)--was investigated by genetic engineering of banana plants for constitutive expression of rice thaumatin-like protein (tlp) gene. Transgene was introduced to cauliflower-like bodies' cluster, induced from meristemic parts of male inflorescences, using particle bombardment with plasmid carrying a rice tlp gene driving by the CaMV 35S promoter. Hygromycin B was used as the selection reagent. The presence and integration of rice tlp gene in genomic DNA confirmed by PCR and Southern blot analyses. RT-PCR revealed the expression of transgene in leaf and root tissues in transformants. Bioassay of transgenic banana plants challenged with Fusarium wilt pathogen showed that expression of TLP enhanced resistance to F. oxysporum sp. cubensec (race 4) compared to control plants.
    Matched MeSH terms: Promoter Regions, Genetic
  13. Editorial notes for the ESPR special issue on Green technology and Industrial Revolution 4.0 for a greener future
    Low SC, Vo DN, Hameed BH, Abd Rahman SB
    Environ Sci Pollut Res Int, 2023 Dec;30(60):124425-124426.
    PMID: 38015403 DOI: 10.1007/s11356-023-31128-w
    Matched MeSH terms: Promoter Regions, Genetic
  14. Increased expression and hotspot mutations of the multidrug efflux transporter, CDR1 in azole-resistant Candida albicans isolates from vaginitis patients
    Looi CY, D' Silva EC, Seow HF, Rosli R, Ng KP, Chong PP
    FEMS Microbiol Lett, 2005 Aug 15;249(2):283-9.
    PMID: 16006060
    The aims of our research were to investigate the gene expression of the multidrug efflux transporter, CDR1 and the major drug facilitator superfamily transporter, MDR1 gene in azole drug-resistant Candida albicans and Candida glabrata clinical isolates recovered from vaginitis patients; and to identify hotspot mutations that may be present in the C. albicans CaCDR1 gene that could be associated with drug-resistance. The relative expression of the CDR1 and MDR1 transcripts in ketoconazole and clotrimazole-resistant isolates and drug-susceptible ATCC strains were determined by semi-quantitative reverse transcription-polymerase chain reaction. Expression of CaCDR1 transcript was upregulated to varying extents in all three azole-resistant C. albicans isolates studied (1.6-, 3.7- and 3.9-fold) and all three C. glabrata isolates tested (at 1.9-, 2.3- and 2.7-fold). The overexpression level of CaCDR1 in the isolates correlated with the degree of resistance as reflected by the minimum inhibitory concentration (MIC) of the drugs. The messenger RNA for another efflux pump, MDR1, was also overexpressed in one of the azole-resistant C. albicans isolates that overexpressed CDR1. This finding suggests that drug-resistance may involve synergy between energy-dependent drug efflux pumps CDR1p and MDR1p in some but not all isolates. Interestingly, DNA sequence analysis of the promoter region of the CaCDR1 gene revealed several point mutations in the resistant clinical isolates compared to the susceptible isolates at 39, 49 and 151 nucleotides upstream from the ATG start codon. This finding provides new information on point mutations in the promoter region which may be responsible for the overexpression of CDR1 in drug-resistant isolates.
    Matched MeSH terms: Promoter Regions, Genetic
  15. Analysis of interleukin-10 promoter single nucleotide polymorphisms and risk of non-Hodgkin lymphoma in a Malaysian population
    Lim YY, Chin YM, Tai MC, Fani S, Chang KM, Ong TC, et al.
    Leuk Lymphoma, 2015 Jan;56(1):163-8.
    PMID: 24684230 DOI: 10.3109/10428194.2014.907895
    We evaluated the association of two IL10 single nucleotide polymorphisms (SNPs) (rs1800896 and rs1800871) with non-Hodgkin lymphoma (NHL) risk in the three major races of the Malaysian population (Malay, Chinese and Indian; 317 cases and 330 controls). Our initial screening demonstrated that rs1800871 but not rs1800896 was significantly associated with increased NHL risk in Malays (pMalay-Rec = 0.007) and Chinese only (pChinese-Rec = 0.039). Subsequent combined analysis of the Malay and Chinese revealed significant association of rs1800871 with all (ALL) NHL subtypes (pMeta-ALL-NHL-Rec = 0.001), ALL B-cell subtypes (pMeta-ALL-B-cell-Rec = 0.003), diffuse large B-cell lymphoma (DLBCL) subtype (pMeta-DLBCL-Rec = 0.002) and ALL T-cell subtypes (pMeta-ALL-T-cell-Rec = 0.031). SNP rs1800896 showed increased risk only in follicular lymphoma (FL) (pMeta-FL-Dom = 0.0004). We also detected a male-specific association of rs1800871 with increased NHL risk (pMeta-Male-ALL-NHL-Rec = 0.006) in the combined analysis. To our knowledge, this is the first report on the association of IL10 promoter SNPs with NHL susceptibility in the three major races of Malaysia.
    Matched MeSH terms: Promoter Regions, Genetic*
  16. Expression of the Na+/H+ antiporter gene (g1-nhaC) of alkaliphilic Bacillus sp. G1 in Escherichia coli
    Liew CW, Illias RM, Mahadi NM, Najimudin N
    FEMS Microbiol Lett, 2007 Nov;276(1):114-22.
    PMID: 17937670
    A Na(+)/H(+) antiporter gene was isolated from alkaliphilic Bacillus sp. G1. The full-length sequence of the Na(+)/H(+) antiporter gene was obtained using a genome walking method, and designated as g1-nhaC. An ORF preceded by a promoter-like sequence and a Shine-Dalgarno sequence, and followed by a terminator-like sequence was identified. The deduced amino acid sequence consists of 535 amino acids, and a calculated molecular mass of 57 776 Da. g1-nhaC was subsequently cloned into pET22b(+) and expressed in Escherichia coli BL21 (DE3). Recombinant E. coli harboring the g1-nhaC gene was able to grow in modified L medium at various concentrations of NaCl (0.2-2.0 M) at different pH values. The recombinant bacteria grew well in the medium with concentrations of NaCl as high as 1.75 M at pH 8.0-9.0. Minimal growth was observed at 2.0 M NaCl, pH 8.0-9.0. At pH 10, the recombinant bacteria grew well in a medium with a low concentration of NaCl (0.2 M). These results suggested that the g1-NhaC antiporter from Bacillus sp. G1 plays a role in Na(+) extrusion at lower pH values and in pH homeostasis at pH 10 under Na(+)-limiting conditions.
    Matched MeSH terms: Promoter Regions, Genetic
  17. Fulltext Lack of association between RANTES-28, SDF-1 gene polymorphisms and systemic lupus erythematosus in the Malaysian population
    Lian LH, Kee BP, Ng HL, Chua KH
    Genet. Mol. Res., 2011;10(4):2841-50.
    PMID: 22095608 DOI: 10.4238/2011.November.17.2
    Regulated on activation, normal T-cell expressed and secreted (RANTES) and stromal cell-derived factor 1 (SDF-1) are members of the CC- and CXC-chemokine families, respectively. Both genes have been postulated to be involved in the pathogenesis of systemic lupus erythematosus (SLE). We analyzed position 28 of the RANTES gene promoter region, as well as the SNP observed in the 3' UTR of the SDF-1 gene at position 801, in 130 patients presenting SLE at the Malaya University Medical Centre. Screening of 130 healthy volunteer controls using RFLP was also performed. RANTES-28 polymorphism analysis showed no significant (P = 0.3520) relationship, even though homozygous C/C was more frequent in SLE patients (OR = 1.4183) and heterozygous C/G was more frequent in healthy controls (OR = 0.7051). There were no significant (P = 0.2650) associations between A/A (OR = 0.783), G/G (OR = 1.5914) and G/A (OR = 0.8289) genotypes in the SDF-1 gene polymorphism with SLE. We conclude that there is no significant association of RANTES-28 and SDF-1 gene polymorphisms and occurrence of SLE in Malaysia.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  18. Estrogen directly stimulates LHb expression at the pituitary level during puberty in female zebrafish
    Li G, Tang H, Chen Y, Yin Y, Ogawa S, Liu M, et al.
    Mol Cell Endocrinol, 2018 02 05;461:1-11.
    PMID: 28801227 DOI: 10.1016/j.mce.2017.08.003
    The LHb expression is up-regulated during puberty in female zebrafish. However, the molecular mechanism underlying how LHb expression is regulated during puberty remains largely unknown. In this study, we found that the mRNA expression levels of lhb, fshb and cyp19a1b were up-regulated along with the puberty onset in zebrafish. Among the three nuclear estrogen receptors (nERs), the esr2b is the only type whose expression is significantly up-regulated during puberty onset in the pituitary. However, in situ hybridization results revealed that lhb mRNA was colocalized with esr1 and esr2a but not esr2b. Exposure to estradiol (E2) significantly stimulates LHb expression in both wild-type and kiss1-/-;kiss2-/-;gnrh3-/- triple knockout pubertal zebrafish. Moreover, exposure of cultured pituitary cells to E2 increased the LHb expression, indicating that the estrogenic effect on LHb expression could be acted at the pituitary level. Finally, we cloned and analyzed the promoter of lhb by luciferase assay. Our results indicated that the E2 responsive regions of lhb promoter for ERα and ERβ2 are identical, suggesting that ERα and ERβ2 could bind to the same half ERE region of the promoter of lhb, exhibiting a classical ERE-dependent pathway. In summary, we demonstrate that E2 could directly act on the pituitary level to stimulate LHb transcription during puberty in zebrafish.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  19. High level expression of thermostable lipase from Geobacillus sp. strain T1
    Leow TC, Rahman RN, Basri M, Salleh AB
    Biosci Biotechnol Biochem, 2004 Jan;68(1):96-103.
    PMID: 14745170
    A thermostable extracellular lipase of Geobacillus sp. strain T1 was cloned in a prokaryotic system. Sequence analysis revealed an open reading frame of 1,251 bp in length which codes for a polypeptide of 416 amino acid residues. The polypeptide was composed of a signal peptide (28 amino acids) and a mature protein of 388 amino acids. Instead of Gly, Ala was substituted as the first residue of the conserved pentapeptide Gly-X-Ser-X-Gly. Successful gene expression was obtained with pBAD, pRSET, pET, and pGEX as under the control of araBAD, T7, T7 lac, and tac promoters, respectively. Among them, pGEX had a specific activity of 30.19 Umg(-1) which corresponds to 2927.15 Ug(-1) of wet cells after optimization. The recombinant lipase had an optimum temperature and pH of 65 degrees C and pH 9, respectively. It was stable up to 65 degrees C at pH 7 and active over a wide pH range (pH 6-11). This study presents a rapid cloning and overexpression, aimed at improving the enzyme yield for successful industrial application.
    Matched MeSH terms: Promoter Regions, Genetic
  20. Founder mutation in the BRCA1 gene in Malay breast cancer patients from Singapore
    Lee AS, Ho GH, Oh PC, Balram C, Ooi LL, Lim DT, et al.
    Hum Mutat, 2003 Aug;22(2):178.
    PMID: 12872263
    The mutation spectrum of the BRCA1 gene among ethnic groups from Asia has not been well studied. We investigated the frequency of mutations in the BRCA1 gene among Malay breast cancer patients from Singapore, independent of family history. By using the protein truncation test (PTT) and direct sequencing, BRCA1 mutations were detected in 6 of 49 (12.2%) unrelated patients. Four novel missense mutations in exon 11, T557A (1788A>G), T582A (1863A>G), N656S (2086A>G) and P684S (2169C>T) were identified in one patient. Two patients had missense mutations in exon 23, V1809A (5545T>C), which has been previously detected in individuals from Central and Eastern Europe. Three unrelated patients had the deleterious 2846insA frameshift mutation in exon 11. Methylation specific PCR (MSP) of the promoter region of the BRCA1 gene detected hypermethylation of tumor DNA in an additional 2 patients. Haplotype analysis using the microsatellite markers D17S855, D17S1323 and D17S1325 revealed a common haplotype for the three unrelated patients and their three relatives with the 2846insA mutation. These findings strongly suggest that the 2846insA mutation, the most common deleterious mutation in this study, may possibly be a founder mutation in breast cancer patients of Malay ethnic background.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
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