Displaying publications 1 - 20 of 49 in total

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  1. Fulltext Advances in Genetic Improvement for Tocotrienol Production: A Review
    Babura SR, Abdullah SNA, Khaza Ai H
    J Nutr Sci Vitaminol (Tokyo), 2017;63(4):215-221.
    PMID: 28978868 DOI: 10.3177/jnsv.63.215
    Tocotrienols are forms of vitamin E that are present in several important food crops. Compared to tocopherols, less research has been conducted on these compounds because of their low bioavailability and distribution in plant tissues. Both tocotrienols and tocopherols are known for their antioxidant and anticancer activities, which are beneficial for both humans and animals. Moreover, tocotrienols possess certain properties which are not found in tocopherols, such as neuroprotective and cholesterol-lowering activities. The contents of tocotrienols in plants vary. Tocotrienols constitute more than 70% and tocopherols less than 30% of the total vitamin E content in palm oil, which is the best source of vitamin E. Accumulation of tocotrienols also occurs in non-photosynthetic tissues, such as the seeds, fruits and latex of some monocotyledonous and dicotyledonous plant species. The use of biotechnological techniques to increase the tocotrienol content in plants, their biological functions, and benefits to human health are discussed in this review.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  2. 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
  3. Association analysis of -429T/C and -374T/A polymorphisms of receptor of advanced glycation end products (RAGE) gene in Malaysian with type 2 diabetic retinopathy
    Ng ZX, Kuppusamy UR, Tajunisah I, Fong KC, Chua KH
    Diabetes Res Clin Pract, 2012 Mar;95(3):372-7.
    PMID: 22154374 DOI: 10.1016/j.diabres.2011.11.005
    Conflicting results have been reported in different populations on the association between two particular RAGE gene polymorphisms (-429T/C and -374T/A) and retinopathy in diabetic patients. Therefore this study was designed to assess the association between both gene polymorphisms with retinopathy in Malaysian diabetic patients. A total of 342 type 2 diabetic patients [171 without retinopathy (DNR) and 171 with retinopathy (DR)] and 235 healthy controls were included in this study. Genomic DNA was obtained from blood samples and the screening for the gene polymorphisms was done using polymerase chain reaction-restriction fragment length polymorphism approach. Overall, the genotype distribution for both polymorphisms was not statistically different (p>0.05) among the control, DNR and DR groups. The -429C minor allele frequency of DR group (12.0%) was not significantly different (p>0.05) when compared to DNR group (16.1%) and healthy controls (11.3%). The -374A allele frequency also did not differ significantly between the control and DNR (p>0.05), control and DR (p>0.05) as well as DNR and DR groups (p>0.05). This is the first study report on RAGE gene polymorphism in Malaysian DR patients. In conclusion, -429T/C and -374T/A polymorphisms in the promoter region of RAGE gene were not associated with Malaysian type 2 DR patients.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  4. Association of CTLA4 gene polymorphisms with lymphatic filariasis in an East Malaysian population
    Idris ZM, Miswan N, Muhi J, Mohd TA, Kun JF, Noordin R
    Hum Immunol, 2011 Jul;72(7):607-12.
    PMID: 21513760 DOI: 10.1016/j.humimm.2011.03.017
    Lymphatic filariasis (LF) is a parasitic disease caused by threadlike worms of the Brugia and Wuchereria species that live in the human lymphatic system. Regulatory T cells (Tregs) may play a key role in the pathogenesis of LF, and cytotoxic T-lymphocyte antigen-4 (CTLA4) expressed by Tregs is a potential candidate gene because it modulates T-cell activation. A case-control study was performed to establish a potential association of 5 CTLA4 gene promoter single nucleotide polymorphisms (SNPs; rs733618, rs11571316, rs5742909, rs231775, and rs16840252) with the occurrence of LF in an East Malaysian population (320 LF-infected individuals and 150 healthy controls). Polymorphisms were evaluated using TaqMan real-time polymerase chain reaction followed by direct sequencing. LF carriers of the rs733618 AG genotypes (p = 0.02) and those with combined minor allele G carriers (AG + GG; p = 0.01) exhibited a significantly decreased risk for LF. Among the asymptomatic amicrofilaremic cases, positive associations were reported for all genotypes and variants of rs733618 with odds ratios (ORs) ranging from 0.27 to 0.45. In the asymptomatic microfilaremic cases, marker rs231775 exhibited a significant decreased risk, with ORs ranging from 0.50 to 0.57. The study has identified SNPs in the CTLA4 promoter gene that may be functionally linked with susceptibility to LF.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  5. Biotechnology of oil palm: strategies towards manipulation of lipid content and composition
    Parveez GK, Rasid OA, Masani MY, Sambanthamurthi R
    Plant Cell Rep, 2015 Apr;34(4):533-43.
    PMID: 25480400 DOI: 10.1007/s00299-014-1722-4
    Oil palm is a major economic crop for Malaysia. The major challenges faced by the industry are labor shortage, availability of arable land and unstable commodity price. This has caused the industry to diversify its applications into higher value products besides increasing its yield. While conventional breeding has its limitations, biotechnology was identified as one of the tools for overcoming the above challenges. Research on biotechnology of oil palm began more than two decades ago leveraging a multidisciplinary approach involving biochemical studies, gene and promoter isolation, transformation vector construction and finally genetic transformation to produce the targeted products. The main target of oil palm biotechnology research is to increase oleic acid in the mesocarp. Other targets are stearic acid, palmitoleic acid, ricinoleic acid, lycopene (carotenoid) and biodegradable plastics. Significant achievements were reported for the biochemical studies, isolation of useful oil palm genes and characterization of important promoters. A large number of transformation constructs for various targeted products were successfully produced using the isolated oil palm genes and promoters. Finally transformation of these constructs into oil palm embryogenic calli was carried out while the regeneration of transgenic oil palm harboring the useful genes is in progress.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  6. Breaking-off tissue specific activity of the oil palm metallothionein-like gene promoter in T(1) seedlings of tomato exposed to metal ions
    Kamaladini H, Nor Akmar Abdullah S, Aziz MA, Ismail IB, Haddadi F
    J Plant Physiol, 2013 Feb 15;170(3):346-54.
    PMID: 23290536 DOI: 10.1016/j.jplph.2012.10.017
    Metallothioneins (MTs) are cysteine-rich metal-binding proteins that are involved in cell growth regulation, transportation of metal ions and detoxification of heavy metals. A mesocarp-specific metallothionein-like gene (MT3-A) promoter was isolated from the oil palm (Elaeis guineensis Jacq). A vector construct containing the MT3-A promoter fused to the β-glucuronidase (GUS) gene in the pCAMBIA 1304 vector was produced and used in Agrobacterium-mediated transformation of tomato. Histochemical GUS assay of different tissues of transgenic tomato showed that the MT3-A promoter only drove GUS expression in the reproductive tissues and organs, including the anther, fruit and seed coat. Competitive RT-PCR and GUS fluorometric assay showed changes in the level of GUS mRNA and enzyme activity in the transgenic tomato (T(0)). No GUS mRNA was found in roots and leaves of transgenic tomato. In contrast, the leaves of transgenic tomato seedlings (T(1)) produced the highest GUS activity when treated with 150 μM Cu(2+) compared to the control (without Cu(2+)). However, Zn(2+) and Fe(2+) treatments did not show GUS expression in the leaves of the transgenic tomato seedlings. Interestingly, the results showed a breaking-off tissue-specific activity of the oil palm MT3-A promoter in T(1) seedlings of tomato when subjected to Cu(2+) ions.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  7. Fulltext CDK9 inhibitors define elongation checkpoints at both ends of RNA polymerase II-transcribed genes
    Laitem C, Zaborowska J, Isa NF, Kufs J, Dienstbier M, Murphy S
    Nat Struct Mol Biol, 2015 May;22(5):396-403.
    PMID: 25849141 DOI: 10.1038/nsmb.3000
    Transcription through early-elongation checkpoints requires phosphorylation of negative transcription elongation factors (NTEFs) by the cyclin-dependent kinase (CDK) 9. Using CDK9 inhibitors and global run-on sequencing (GRO-seq), we have mapped CDK9 inhibitor-sensitive checkpoints genome wide in human cells. Our data indicate that early-elongation checkpoints are a general feature of RNA polymerase (pol) II-transcribed human genes and occur independently of polymerase stalling. Pol II that has negotiated the early-elongation checkpoint can elongate in the presence of inhibitors but, remarkably, terminates transcription prematurely close to the terminal polyadenylation (poly(A)) site. Our analysis has revealed an unexpected poly(A)-associated elongation checkpoint, which has major implications for the regulation of gene expression. Interestingly, the pattern of modification of the C-terminal domain of pol II terminated at this new checkpoint largely mirrors the pattern normally found downstream of the poly(A) site, thus suggesting common mechanisms of termination.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  8. Characterization of promoter of EgPAL1, a novel PAL gene from the oil palm Elaeis guineensis Jacq
    Yusuf CYL, Abdullah JO, Shaharuddin NA, Abu Seman I, Abdullah MP
    Plant Cell Rep, 2018 Feb;37(2):265-278.
    PMID: 29090330 DOI: 10.1007/s00299-017-2228-7
    KEY MESSAGE: The oil palm EgPAL1 gene promoter and its regulatory region were functional as a promoter in the heterologous system of Arabidopsis according to the cis-acting elements present in that region. The promoter was developmentally regulated, vascular tissue specific and responsive to water stress agents. Phenylalanine ammonia lyase (PAL, EC 4.3.1.24) is the key enzyme of the phenylpropanoid pathway which plays important roles in plant development and adaptation. To date, there is no report on the study of PAL from oil palm (Elaeis guineensis), an economically important oil crop. In this study, the 5' regulatory sequence of a highly divergent oil palm PAL gene (EgPAL1) was isolated and fused with GUS in Arabidopsis to create two transgenic plants carrying the minimal promoter with (2302 bp) and without its regulatory elements (139 bp). The regulatory sequence contained cis-acting elements known to be important for plant development and stress response including the AC-II element for lignin biosynthesis and several stress responsive elements. The promoter and its regulatory region were fully functional in Arabidopsis. Its activities were characterised by two common fundamental features of PAL which are responsive to plant internal developmental programme and external factors. The promoter was developmentally regulated in certain organs; highly active in young organs but less active or inactive in mature organs. The presence of the AC elements and global activity of the EgPAL1 promoter in all organs resembled the property of lignin-related genes. The existence of the MBS element and enhancement of the promoter activity by PEG reflected the behaviour of drought-responsive genes. Our findings provide a platform for evaluating oil palm gene promoters in the heterologous system of Arabidopsis and give insights into the activities of EgPAL1 promoter in oil palm.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  9. 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
  10. Contribution of the MLH1 -93G>a promoter polymorphism in modulating susceptibility risk in Malaysian colorectal cancer patients
    Nizam ZM, Abdul Aziz AA, Kaur G, Abu Hassan MR, Mohd Sidek AS, Yeh LY, et al.
    Asian Pac J Cancer Prev, 2013;14(2):619-24.
    PMID: 23621208
    BACKGROUND: Colorectal cancer (CRC) exists in a more common sporadic form and less common hereditary forms, associated with the Lynch syndrome, familial adenomatous polyposis (FAP) and other rare syndromes. Sporadic CRC is believed to arise as a result of close interaction between environmental factors, including dietary and lifestyle habits, and genetic predisposition factors. In contrast, hereditary forms such as those related to the Lynch syndrome result from inheritance of germline mutations of mismatch repair (MMR) genes. However, in certain cases, the influence of low penetrance alleles in familial colorectal cancer susceptibility is also undeniable.

    AIM: To investigate the genotype frequencies of MLH1 promoter polymorphism -93G>A and to determine whether it could play any role in modulating familial and sporadic CRC susceptibility risk.

    METHODS: A case-control study comprising of 104 histopathologically confirmed CRC patients as cases (52 sporadic CRC and 52 Lynch syndrome patients) and 104 normal healthy individuals as controls was undertaken. DNA was extracted from peripheral blood and the polymorphism was genotyped employing PCR-RFLP methods. The genotypes were categorized into homozygous wild type, heterozygous and homozygous variants. The risk association between these polymorphisms and CRC susceptibility risk was calculated using binary logistic regression analysis and deriving odds ratios (ORs).

    RESULTS: When risk association was investigated for all CRC patients as a single group, the heterozygous (G/A) genotype showed a significantly higher risk for CRC susceptibility with an OR of 2.273, (95%CI: 1.133-4.558 and p-value=0.021). When analyzed specifically for the 2 types of CRC, the heterozygous (G/A) genotype showed significantly higher risk for sporadic CRC susceptibility with and OR of 3.714, (95%CI: 1.416-9.740 and p-value=0.008). Despite high OR value was observed for Lynch syndrome (OR: 1.600, 95%CI: 0.715-3.581), the risk was not statistically significant (P=0.253).

    CONCLUSION: Our results suggest an influence of MLH1 promoter polymorphism -93G>A in modulating susceptibility risk in Malaysian CRC patients, especially those with sporadic disease.

    Matched MeSH terms: Promoter Regions, Genetic/genetics
  11. Cyp2a5 Promoter-based Gene Reporter Assay: A Novel Design of Cell-based Bioassay for Toxicity Prediction
    Abu-Bakar A, Hu H, Lang MA
    Basic Clin Pharmacol Toxicol, 2018 Sep;123 Suppl 5:72-80.
    PMID: 29788535 DOI: 10.1111/bcpt.13046
    The murine cytochrome P450 2a5 (Cyp2a5) gene is regulated by complex interactions of various stress-activated transcription factors (TFs). Elevated Cyp2a5 transcription under chemical-induced stress conditions is achieved by interplay between the various TFs - including as aryl hydrocarbon receptor (AhR) and nuclear factor (erythroid-derived 2)-like 2 wild-type (Nrf2) - at the 'stress-responding' cluster of response elements on the Cyp2a5 promoter, as well as through mRNA stabilization mediated by interaction of the stress-activated heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) with the 3'-UTR of the CYP2A5 mRNA. We designed a unique toxicity pathway-based reporter assay to include regulatory regions from both the 5' and the 3' untranslated regions of Cyp2a5 in a luciferase reporter plasmid to reflect in vivo responses to chemical insult. Human breast cancer MCF-7 cells were stably transfected with pGL4.38-Cyp2a5_Wt3k (wild-type) or mutant - pGL4.38-Cyp2a5_StREMut and pGL4.38-Cyp2a5_XREMut - reporter gene to monitor chemical-induced cellular response mediated by AhR and Nrf2 signalling. The recombinant cells were treated with representative of AhR agonist, polycyclic aromatic hydrocarbons, brominated flame retardant, fluorosurfactant, aromatic organic compound and metal, to determine the sensitivity of the Cyp2a5 promoter-based gene reporter assays to chemical insults by measuring the LC50 and EC50 of the respective chemicals. The three assays are sensitive to sublethal cellular responses of chemicals, which is an ideal feature for toxicity pathway-based bioassay for toxicity prediction. The wild-type reporter responded well to chemicals that activate crosstalk between the AhR and Nrf2, whilst the mutant reporters effectively gauge cellular response driven by either Nrf2/StRE or AhR/XRE signalling. Thus, the three gene reporter assays could be used tandemly to determine the predominant toxicity pathway of a given compound.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  12. Detection of Oil Palm Root Penetration by Agrobacterium-Mediated Transformed Ganoderma boninense, Expressing Green Fluorescent Protein
    Govender N, Wong MY
    Phytopathology, 2017 04;107(4):483-490.
    PMID: 27918241 DOI: 10.1094/PHYTO-02-16-0062-R
    A highly efficient and reproducible Agrobacterium-mediated transformation protocol for Ganoderma boninense was developed to facilitate observation of the early stage infection of basal stem rot (BSR). The method was proven amenable to different explants (basidiospore, protoplast, and mycelium) of G. boninense. The transformation efficiency was highest (62%) under a treatment combination of protoplast explant and Agrobacterium strain LBA4404, with successful expression of an hyg marker gene and gus-gfp fusion gene under the control of heterologous p416 glyceraldehyde 3-phosphate dehydrogenase promoter. Optimal transformation conditions included a 1:100 Agrobacterium/explant ratio, induction of Agrobacterium virulence genes in the presence of 250 μm acetosyringone, co-cultivation at 22°C for 2 days on nitrocellulose membrane overlaid on an induction medium, and regeneration of transformants on potato glucose agar prepared with 0.6 M sucrose and 20 mM phosphate buffer. Evaluated transformants were able to infect root tissues of oil palm plantlets with needle-like microhyphae during the penetration event. The availability of this model pathogen system for BSR may lead to a better understanding of the pathogenicity factors associated with G. boninense penetration into oil palm roots.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  13. Dietary fat interacts with the -514C>T polymorphism in the hepatic lipase gene promoter on plasma lipid profiles in a multiethnic Asian population: the 1998 Singapore National Health Survey
    Tai ES, Corella D, Deurenberg-Yap M, Cutter J, Chew SK, Tan CE, et al.
    J Nutr, 2003 Nov;133(11):3399-408.
    PMID: 14608050 DOI: 10.1093/jn/133.11.3399
    We have previously reported an interaction between -514C>T polymorphism at the hepatic lipase (HL) gene and dietary fat on high-density lipoprotein-cholesterol (HDL-C) metabolism in a representative sample of white subjects participating in the Framingham Heart Study. Replication of these findings in other populations will provide proof for the relevance and consistency of this marker as a tool for risk assessment and more personalized cardiovascular disease prevention. Therefore, we examined this gene-nutrient interaction in a representative sample of Singaporeans (1324 Chinese, 471 Malays and 375 Asian Indians) whose dietary fat intake was recorded by a validated questionnaire. When no stratification by fat intake was considered, the T allele was associated with higher plasma HDL-C concentrations (P = 0.001), higher triglyceride (TG) concentrations (P = 0.001) and higher HDL-C/TG ratios (P = 0.041). We found a highly significant interaction (P = 0.001) between polymorphism and fat intake in determining TG concentration and the HDL-C/TG ratio (P = 0.001) in the overall sample even after adjustment for potential confounders. Thus, TT subjects showed higher TG concentrations only when fat intake supplied >30% of total energy. This interaction was also found when fat intake was considered as continuous (P = 0.035). Moreover, in the upper tertile of fat intake, TT subjects had 45% more TG than CC individuals (P < 0.01). For HDL-C concentration, the gene-diet interaction was significant (P = 0.015) only in subjects of Indian origin. In conclusion, our results indicate that there are differences in the association of -514C>T polymorphism with plasma lipids according to dietary intake and ethnic background. Specifically, the TT genotype is associated with a more atherogenic lipid profile when subjects consume diets with a fat content > 30%.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  14. Fulltext Differential expression and role of hyperglycemia induced oxidative stress in epigenetic regulation of β1, β2 and β3-adrenergic receptors in retinal endothelial cells
    Safi SZ, Qvist R, Yan GO, Ismail IS
    BMC Med Genomics, 2014;7:29.
    PMID: 24885710 DOI: 10.1186/1755-8794-7-29
    Aberrant epigenetic profiles are concomitant with a spectrum of developmental defects and diseases. Role of methylation is an increasingly accepted factor in the pathophysiology of diabetes and its associated complications. This study aims to examine the correlation between oxidative stress and methylation of β1, β2 and β3-adrenergic receptors and to analyze the differential variability in the expression of these genes under hyperglycemic conditions.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  15. Fulltext EgJUB1 and EgERF113 transcription factors as potential master regulators of defense response in Elaeis guineensis against the hemibiotrophic Ganoderma boninense
    Sakeh NM, Abdullah SNA, Bahari MNA, Azzeme AM, Shaharuddin NA, Idris AS
    BMC Plant Biol, 2021 Jan 22;21(1):59.
    PMID: 33482731 DOI: 10.1186/s12870-020-02812-7
    BACKGROUND: Hemibiotrophic pathogen such as the fungal pathogen Ganoderma boninense that is destructive to oil palm, manipulates host defense mechanism by strategically switching from biotrophic to necrotrophic phase. Our previous study revealed two distinguishable expression profiles of oil palm genes that formed the basis in deducing biotrophic phase at early interaction which switched to necrotrophic phase at a later stage of infection.

    RESULTS: The present report is a continuing study from our previous published transcriptomic profiling of oil palm seedlings against G. boninense. We focused on identifying differentially expressed genes (DEGs) encoding transcription factors (TFs) from the same RNA-seq data; resulting in 106 upregulated and 108 downregulated TFs being identified. The DEGs are involved in four established defense-related pathways responsible for cell wall modification, reactive oxygen species (ROS)-mediated signaling, programmed cell death (PCD) and plant innate immunity. We discovered upregulation of JUNGBRUNNEN 1 (EgJUB1) during the fungal biotrophic phase while Ethylene Responsive Factor 113 (EgERF113) demonstrated prominent upregulation when the palm switches to defense against necrotrophic phase. EgJUB1 was shown to have a binding activity to a 19 bp palindromic SNBE1 element, WNNYBTNNNNNNNAMGNHW found in the promoter region of co-expressing EgHSFC-2b. Further in silico analysis of promoter regions revealed co-expression of EgJUB1 with TFs containing SNBE1 element with single nucleotide change at either the 5th or 18th position. Meanwhile, EgERF113 binds to both GCC and DRE/CRT elements promoting plasticity in upregulating the downstream defense-related genes. Both TFs were proven to be nuclear-localized based on subcellular localization experiment using onion epidermal cells.

    CONCLUSION: Our findings demonstrated unprecedented transcriptional reprogramming of specific TFs potentially to enable regulation of a specific set of genes during different infection phases of this hemibiotrophic fungal pathogen. The results propose the intricacy of oil palm defense response in orchestrating EgJUB1 during biotrophic and EgERF113 during the subsequent transition to the necrotrophic phase. Binding of EgJUB1 to SNBE motif instead of NACBS while EgERF113 to GCC-box and DRE/CRT motifs is unconventional and not normally associated with pathogen infection. Identification of these phase-specific oil palm TFs is important in designing strategies to tackle or attenuate the progress of infection.

    Matched MeSH terms: Promoter Regions, Genetic/genetics
  16. Fulltext Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA) and HIV-1 nef Genes in Escherichia coli
    Mualif SA, Teow SY, Omar TC, Chew YW, Yusoff NM, Ali SA
    PLoS One, 2015;10(7):e0130446.
    PMID: 26147991 DOI: 10.1371/journal.pone.0130446
    Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW) rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef), HIV-1 p24 (ca), and HIV-1 vif in NiCo21(DE3) E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  17. Fulltext Epigenetic Control of the Vasopressin Promoter Explains Physiological Ability to Regulate Vasopressin Transcription in Dehydration and Salt Loading States in the Rat
    Greenwood MP, Greenwood M, Gillard BT, Loh SY, Paton JF, Murphy D
    J Neuroendocrinol, 2016 04;28(4).
    PMID: 26833868 DOI: 10.1111/jne.12371
    The synthesis of arginine vasopressin (AVP) in the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the hypothalamus is sensitive to increased plasma osmolality and a decreased blood volume, and thus is robustly increased by both dehydration (increased plasma osmolality and decreased blood volume) and salt loading (increased plasma osmolality). Both stimuli result in functional remodelling of the SON and PVN, a process referred to as functional-related plasticity. Such plastic changes in the brain have recently been associated with altered patterns of DNA methylation at CpG (cytosine-phosphate-guanine) residues, a process considered to be important for the regulation of gene transcription. In this regard, the proximal Avp promoter contains a number of CpG sites and is recognised as one of four CpG islands for the Avp gene, suggesting that methylation may be regulating Avp transcription. In the present study, we show that, in an immortalised hypothalamic cell line 4B, the proximal Avp promoter is highly methylated, and treatment of these cells with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine to demethylate DNA dramatically increases basal and stimulated Avp biosynthesis. We report no changes in the expression of DNA methyltransferases, Dnmt1 and Dnmt3a, whereas there is decreased expression of the demethylating enzyme ten-eleven-translocation 2, Tet2, in the SON by dehydration and salt loading. We found higher methylation of the SON Avp promoter in dehydrated but not salt-loaded rats. By analysis of individual CpG sites, we observed hypomethylation, hypermethylation and no change in methylation of specific CpGs in the SON Avp promoter of the dehydrated rat. Using reporter gene assays, we show that mutation of individual CpGs can result in altered Avp promoter activity. We propose that methylation of the SON Avp promoter is necessary to co-ordinate the duel inputs of increased plasma osmolality and decreased blood volume on Avp transcription in the chronically dehydrated rat.
    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. Fulltext Ets and GATA transcription factors play a critical role in PMA-mediated repression of the ckβ promoter via the protein kinase C signaling pathway
    Kuan CS, Yee YH, See Too WC, Few LL
    PLoS One, 2014;9(12):e113485.
    PMID: 25490397 DOI: 10.1371/journal.pone.0113485
    Choline kinase is the most upstream enzyme in the CDP-choline pathway. It catalyzes the phosphorylation of choline to phosphorylcholine in the presence of ATP and Mg2+ during the biosynthesis of phosphatidylcholine, the major phospholipid in eukaryotic cell membranes. In humans, choline kinase (CK) is encoded by two separate genes, ckα and ckβ, which produce three isoforms, CKα1, CKα2, and CKβ. Previous studies have associated ckβ with muscle development; however, the molecular mechanism underlying the transcriptional regulation of ckβ has never been elucidated.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  20. Evaluation of different promoters driving the GFP reporter gene and selected target tissues for particle bombardment of Dendrobium Sonia 17
    Tee CS, Marziah M, Tan CS, Abdullah MP
    Plant Cell Rep, 2003 Jan;21(5):452-8.
    PMID: 12789448
    Three different morphological callus types, identified as type A, B and C, and tips of in vitro inflorescences were used as target tissues for genetic transformation. Five different DNA plasmids carrying a synthetic green fluorescent protein (gfp) gene driven by different promoters, CaMV 35S, HBT, and Ubi1 were tested for the genetic transformation of Dendrobium Sonia 17. 35S-sgfp-TYG-nos (p35S) with the CaMV 35S promoter showed the highest GFP transient expression rate, while the HBT and Ubi1 promoters showed a relatively lower expression rate in all of the target tissues tested. The highest number of GFP-expressing cells was observed on day 2 post-bombardment, and the number declined gradually over the course of the next 2 weeks. Type A and B callus were found to be the best potential target tissues for genetic transformation.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
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