Displaying publications 1 - 20 of 49 in total

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  1. Badai SS, Rasid OA, Masani MYA, Chan KL, Chan PL, Shaharuddin NA, et al.
    J Plant Physiol, 2023 Oct;289:154080.
    PMID: 37699261 DOI: 10.1016/j.jplph.2023.154080
    Modification of lipid composition in the mesocarp tissue of oil palm involves genetic manipulation of multiple genes. More than one mesocarp-preferential promoter is necessary for the expression of individual transgenes in the same plant to obviate transcriptional gene silencing. This study aimed to identify genes that are preferentially expressed in the mesocarp tissue and characterize selected candidate mesocarp-preferential promoters. Ten transcripts that were preferentially expressed in the mesocarp tissue were identified from the analysis of 82 transcriptome datasets of 12 different oil palm tissues. The expression of two candidate genes, MSP-C1 and MSP-C6, was verified to be preferentially expressed in the mesocarp tissues and shown to have a low expression level in non-mesocarp tissues by reverse transcription quantitative real-time PCR (RT-qPCR). MSP-C6 promoter fragments of different lengths were transformed into tomato plants for further characterization. Both unripe and ripe fruits of transgenic tomato plants transformed with a construct harboring the MSP-C6-F1 (2014 bp) promoter were shown to have high beta-glucuronidase (GUS) activities. The findings of this study suggest the potential applications of the MSP-C6 promoter as a molecular tool for genetic engineering of novel traits in fruit crops.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  2. Halim MA, Choo QC, Ghazali AHA, Wajidi MFF, Najimudin N
    Lett Appl Microbiol, 2021 May;72(5):610-618.
    PMID: 33525052 DOI: 10.1111/lam.13455
    Paenibacillus durus strain ATCC 35681T is a Gram-positive diazotroph that displayed capability of fixing nitrogen even in the presence of nitrate or ammonium. However, the nitrogen fixation activity was detected only at day 1 of growth when cultured in liquid nitrogen-enriched medium. The transcripts of all the nifH homologues were present throughout the 9-day study. When grown in nitrogen-depleted medium, nitrogenase activities occurred from day 1 until day 6 and the nifH transcripts were also present during the course of the study albeit at different levels. In both studies, the absence of nitrogen fixation activity regardless of the presence of the nifH transcripts raised the possibility of a post-transcriptional or post-translational regulation of the system. A putative SigA box sequence was found upstream of the transcription start site of nifB1, the first gene in the major nitrogen fixation cluster. The upstream region of nifB2 showed a promoter recognizable by SigE, a sigma factor normally involved in sporulation.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  3. Annuar AA, Ankathil R, Mohd Yunus N, Husin A, Ab Rajab NS, Abdul Aziz AA, et al.
    Asian Pac J Cancer Prev, 2021 Feb 01;22(2):565-571.
    PMID: 33639675 DOI: 10.31557/APJCP.2021.22.2.565
    BACKGROUND: The FAS mediated apoptosis pathway involving the FAS and FASL genes plays a crucial role in the regulation of apoptotic cell death and imatinib mesylate (IM) mechanism of action. Promoter polymorphisms FAS-670 A>G and FAS-844 T>C which alter the transcriptional activity of these genes may grant a risk to develop cancer and revamp the drug activities towards the cancer cell. We investigated the association of these two polymorphisms with the susceptibility risk and IM treatment response in Malaysian chronic myeloid leukaemia (CML) patients.

    METHODS: This is a retrospective study, which included 93 CML patients and 98 controls. The polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method was used to genotype the FAS and FASL polymorphisms. Data nanlysis was done using SPSS Version 22. The associations of the genotypes with susceptibility risk and IM response in CML patients were assessed by means of logistic regression analysis and deriving odds ratio with 95% CI.

    RESULTS: We observed a significant association between FASL-844T>C polymorphism and CML susceptibility risk and IM response. Variant C allele and FASL-844 CC variant genotype carriers had significantly higher risk for CML susceptibility (OR 1.756, CI 1.163-2.652, p=0.007 and OR 2.261, CI 1.013-5.047, p=0.047 respectively). Conversely, the heterozygous genotype FASL-844 TC conferred lower risk for CML susceptibility (OR 0.379, CI 0.176-0.816, p=0.013). The heterozygous and homozygous variant genotypes and variant C alleles were found to confer a lower risk for the development of IM resistance with OR 0.129 (95% CI: 0.034-0.489 p=0.003), OR 0.257 (95% CI: 0.081-0.818, p=0.021), and OR 0.486 (95% CI: 0.262-0.899, p=0.021) respectively. We also found that FAS-670 A>G polymorphism was not associated with CML susceptibility risk or IM response.

    CONCLUSION: The genetic polymorphism FASL-844 T>C may contribute to the CML susceptibility risk and also IM treatment response in CML patients. Accodringly, it may be useful as a biomarker for predicting CML susceptibility risk and IM resistance.

    Matched MeSH terms: Promoter Regions, Genetic/genetics
  4. 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
  5. Poon CH, Heng BC, Lim LW
    Ann N Y Acad Sci, 2021 01;1484(1):9-31.
    PMID: 32808327 DOI: 10.1111/nyas.14458
    Advances in characterizing molecular profiles provide valuable insights and opportunities for deciphering the neuropathology of depression. Although abnormal brain-derived neurotrophic factor (BDNF) expression in depression has gained much support from preclinical and clinical research, how it mediates behavioral alterations in the depressed state remains largely obscure. Environmental factors contribute significantly to the onset of depression and produce robust epigenetic changes. Epigenetic regulation of BDNF, as one of the most characterized gene loci in epigenetics, has recently emerged as a target in research on memory and psychiatric disorders. Specifically, epigenetic alterations of BDNF exons are heavily involved in mediating memory functions and antidepressant effects. In this review, we discuss key research on stress-induced depression from both preclinical and clinical studies, which revealed that differential epigenetic regulation of specific BDNF exons is associated with depression pathophysiology. Considering that BDNF has a central role in depression, we argue that memory extinction, an adaptive response to fear exposure, is dependent on BDNF modulation and holds promise as a prospective target for alleviating or treating depression and anxiety disorders.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  6. Alhaji SY, Nordin N, Ngai SC, Al Abbar A, Mei L, Abdullah S
    Gene, 2020 Oct 20;758:144958.
    PMID: 32683073 DOI: 10.1016/j.gene.2020.144958
    Short-lived therapeutic gene expression in mammalian cells by DNA methylation is one of the major challenges in gene therapy. In this study, we assessed the implication of DNA methylation on the duration of GFP expression in mouse embryonic stem (ES) and mouse induced pluripotent stem (iPS) cells. The cells were transduced with lentivirus (LV) carrying green fluorescent protein (GFP) driven by either human elongation factor (EF1α) or cytomegalovirus (CMV) promoter. Transduced iPS cells exhibited higher percentage of GFP+ cells with persistent mean fluorescent intensity than transduced ES cells. Analysis on the integrated copy of transgene in the population of the transduced cells demonstrated similar copy number. However, significant increase in GFP intensity following 5-azaC treatment was observed in transduced ES cells only, suggesting the influence of DNA methylation in transgene silencing. Subsequent DNA methylation analysis showed that the promoter and the GFP region of the provirus in iPS cells had negligible methylation profile compared to transduced ES cells. Interestingly, sustained transgene expression was observed upon directed differentiation of transduced iPS cells towards CD34+ CD45+ cells. Hence, this study has shown that favourable transgene activity from lentiviral transduced iPS cells was due to the lack of methylation at the proviral regions.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  7. 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*
  8. 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
  9. 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*
  10. Nabil Fikri RM, Norlelawati AT, Nour El-Huda AR, Hanisah MN, Kartini A, Norsidah K, et al.
    J Psychiatr Res, 2017 05;88:28-37.
    PMID: 28086126 DOI: 10.1016/j.jpsychires.2016.12.020
    The epigenetic changes of RELN that are involved in the development of dopaminergic neurons may fit the developmental theory of schizophrenia. However, evidence regarding the association of RELN DNA methylation with schizophrenia is far from sufficient, as studies have only been conducted on a few limited brain samples. As DNA methylation in the peripheral blood may mirror the changes taking place in the brain, the use of peripheral blood for a DNA methylation study in schizophrenia is feasible due to the scarcity of brain samples. Therefore, the aim of our study was to examine the relationship of DNA methylation levels of RELN promoters with schizophrenia using genomic DNA derived from the peripheral blood of patients with the disorder. The case control studies consisted of 110 schizophrenia participants and 122 healthy controls who had been recruited from the same district. After bisufhite conversion, the methylation levels of the DNA samples were calculated based on their differences of the Cq values assayed using the highly sensitive real-time MethyLight TaqMan® procedure. A significantly higher level of methylation of the RELN promoter was found in patients with schizophrenia compared to controls (p = 0.005) and also in males compared with females (p = 0.004). Subsequently, the RELN expression of the methylated group was 25 fold less than that of the non-methylated group. Based upon the assumption of parallel methylation changes in the brain and peripheral blood, we concluded that RELN DNA methylation might contribute to the pathogenesis of schizophrenia. However, the definite effects of methylation on RELN function during development and also in adult life still require further elaboration.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  11. 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
  12. Azzeme AM, Abdullah SNA, Aziz MA, Wahab PEM
    Plant Physiol Biochem, 2017 Mar;112:129-151.
    PMID: 28068641 DOI: 10.1016/j.plaphy.2016.12.025
    Dehydration-responsive element binding (DREB) transcription factor plays an important role in controlling the expression of abiotic stress responsive genes. An intronless oil palm EgDREB1 was isolated and confirmed to be a nuclear localized protein. Electrophoretic mobility shift and yeast one-hybrid assays validated its ability to interact with DRE/CRT motif. Its close evolutionary relation to the dicot NtDREB2 suggests a universal regulatory role. In order to determine its involvement in abiotic stress response, functional characterization was performed in oil palm seedlings subjected to different levels of drought severity and in EgDREB1 transgenic tomato seedlings treated by abiotic stresses. Its expression in roots and leaves was compared with several antioxidant genes using quantitative real-time PCR. Early accumulation of EgDREB1 in oil palm roots under mild drought suggests possible involvement in the initiation of signaling communication from root to shoot. Ectopic expression of EgDREB1 in T1 transgenic tomato seedlings enhanced expression of DRE/CRT and non-DRE/CRT containing genes, including tomato peroxidase (LePOD), ascorbate peroxidase (LeAPX), catalase (LeCAT), superoxide dismutase (LeSOD), glutathione reductase (LeGR), glutathione peroxidase (LeGP), heat shock protein 70 (LeHSP70), late embryogenesis abundant (LeLEA), metallothionine type 2 (LeMET2), delta 1-pyrroline-5- carboxylate synthetase (LePCS), ABA-aldehyde oxidase (LeAAO) and 9-cis- Epoxycarotenoid dioxygenase (LeECD) under PEG treatment and cold stress (4 °C). Altogether, these findings suggest that EgDREB1 is a functional regulator in enhancing tolerance to drought and cold stress.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  13. 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
  14. Samuel MS, Rath N, Masre SF, Boyle ST, Greenhalgh DA, Kochetkova M, et al.
    Genesis, 2016 Dec;54(12):636-646.
    PMID: 27775859 DOI: 10.1002/dvg.22988
    The serine/threonine kinases ROCK1 and ROCK2 are central mediators of actomyosin contractile force generation that act downstream of the RhoA small GTP-binding protein. As a result, they have key roles in regulating cell morphology and proliferation, and have been implicated in numerous pathological conditions and diseases including hypertension and cancer. Here we describe the generation of a gene-targeted mouse line that enables CRE-inducible expression of a conditionally-active fusion between the ROCK2 kinase domain and the hormone-binding domain of a mutated estrogen receptor (ROCK2:ER). This two-stage system of regulation allows for tissue-selective expression of the ROCK2:ER fusion protein, which then requires administration of estrogen analogues such as tamoxifen or 4-hydroxytamoxifen to elicit kinase activity. This conditional gain-of-function system was validated in multiple tissues by crossing with mice expressing CRE recombinase under the transcriptional control of cytokeratin14 (K14), murine mammary tumor virus (MMTV) or cytochrome P450 Cyp1A1 (Ah) promoters, driving appropriate expression in the epidermis, mammary or intestinal epithelia respectively. Given the interest in ROCK signaling in normal physiology and disease, this mouse line will facilitate research into the consequences of ROCK activation that could be used to complement conditional knockout models. Birth Defects Research (Part A) 106:636-646, 2016. © 2016 Wiley Periodicals, Inc.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  15. Ghoussaini M, French JD, Michailidou K, Nord S, Beesley J, Canisus S, et al.
    Am J Hum Genet, 2016 Oct 06;99(4):903-911.
    PMID: 27640304 DOI: 10.1016/j.ajhg.2016.07.017
    Genome-wide association studies (GWASs) have revealed increased breast cancer risk associated with multiple genetic variants at 5p12. Here, we report the fine mapping of this locus using data from 104,660 subjects from 50 case-control studies in the Breast Cancer Association Consortium (BCAC). With data for 3,365 genotyped and imputed SNPs across a 1 Mb region (positions 44,394,495-45,364,167; NCBI build 37), we found evidence for at least three independent signals: the strongest signal, consisting of a single SNP rs10941679, was associated with risk of estrogen-receptor-positive (ER+) breast cancer (per-g allele OR ER+ = 1.15; 95% CI 1.13-1.18; p = 8.35 × 10-30). After adjustment for rs10941679, we detected signal 2, consisting of 38 SNPs more strongly associated with ER-negative (ER-) breast cancer (lead SNP rs6864776: per-a allele OR ER- = 1.10; 95% CI 1.05-1.14; p conditional = 1.44 × 10-12), and a single signal 3 SNP (rs200229088: per-t allele OR ER+ = 1.12; 95% CI 1.09-1.15; p conditional = 1.12 × 10-05). Expression quantitative trait locus analysis in normal breast tissues and breast tumors showed that the g (risk) allele of rs10941679 was associated with increased expression of FGF10 and MRPS30. Functional assays demonstrated that SNP rs10941679 maps to an enhancer element that physically interacts with the FGF10 and MRPS30 promoter regions in breast cancer cell lines. FGF10 is an oncogene that binds to FGFR2 and is overexpressed in ∼10% of human breast cancers, whereas MRPS30 plays a key role in apoptosis. These data suggest that the strongest signal of association at 5p12 is mediated through coordinated activation of FGF10 and MRPS30, two candidate genes for breast cancer pathogenesis.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
  16. 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*
  17. 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
  18. Khor GH, Froemming GR, Zain RB, Abraham TM, Lin TK
    Asian Pac J Cancer Prev, 2016;17(1):219-23.
    PMID: 26838213
    BACKGROUND: Promoter hypermethylation is a frequent epigenetic mechanism for gene transcription repression in cancer and is one of the hallmarks of the disease. Cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3) contributes to cell contact-mediated communication. Dysregulation of promoter methylation has been reported in various cancers.

    OBJECTIVES: The objectives of this study were to investigate the CELSR3 hypermethylation level in oral squamous cell carcinomas (OSCCs) using methylation-sensitive high-resolution melting analysis (MS-HRM) and to correlate CELSR3 methylation with patient demographic and clinicopathological parameters.

    MATERIALS AND METHODS: Frozen tissue samples of healthy subjects' normal mucosa and OSCCs were examined with regard to their methylation levels of the CELSR3 gene using MS-HRM.

    RESULTS: MS-HRM analysis revealed a high methylation level of CELSR3 in 86% of OSCC cases. Significant correlations were found between CELSR3 quantitative methylation levels with patient ethnicity (P=0.005), age (P=0.024) and pathological stages (P=0.004). A moderate positive correlation between CELSR3 and patient age was also evident (R=0.444, P=0.001).

    CONCLUSIONS: CELSR3 promoter hypermethylation may be an important mechanism involved in oral carcinogenesis. It may thus be used as a biomarker in OSCC prognostication.

    Matched MeSH terms: Promoter Regions, Genetic/genetics
  19. Chalertpet K, Pakdeechaidan W, Patel V, Mutirangura A, Yanatatsaneejit P
    Cancer Sci, 2015 Oct;106(10):1333-40.
    PMID: 26250467 DOI: 10.1111/cas.12761
    Human papillomavirus (HPV) oncoproteins drive distinctive promoter methylation patterns in cancer. However, the underlying mechanism remains to be elucidated. Cyclin A1 (CCNA1) promoter methylation is strongly associated with HPV-associated cancer. CCNA1 methylation is found in HPV-associated cervical cancers, as well as in head and neck squamous cell cancer. Numerous pieces of evidence suggest that E7 may drive CCNA1 methylation. First, the CCNA1 promoter is methylated in HPV-positive epithelial lesions after transformation. Second, the CCNA1 promoter is methylated at a high level when HPV is integrated into the human genome. Finally, E7 has been shown to interact with DNA methyltransferase 1 (Dnmt1). Here, we sought to determine the mechanism by which E7 increases methylation in cervical cancer by using CCNA1 as a gene model. We investigated whether E7 induces CCNA1 promoter methylation, resulting in the loss of expression. Using both E7 knockdown and overexpression approaches in SiHa and C33a cells, our data showed that CCNA1 promoter methylation decreases with a corresponding increase in expression in E7 siRNA-transfected cells. By contrast, CCNA1 promoter methylation was augmented with a corresponding reduction in expression in E7-overexpressing cells. To confirm whether the binding of the E7-Dnmt1 complex to the CCNA1 promoter induced methylation and loss of expression, ChIP assays were carried out in E7-, del CR3-E7 and vector control-overexpressing C33a cells. The data showed that E7 induced CCNA1 methylation by forming a complex with Dnmt1 at the CCNA1 promoter, resulting in the subsequent reduction of expression in cancers. It is interesting to further explore the genome-wide mechanism of E7 oncoprotein-mediated DNA methylation.
    Matched MeSH terms: Promoter Regions, Genetic/genetics*
  20. Ahammad AK, Asaduzzaman M, Asakawa S, Watabe S, Kinoshita S
    Mech. Dev., 2015 Aug;137:53-65.
    PMID: 25842264 DOI: 10.1016/j.mod.2015.02.006
    Teleosts are unique among vertebrates due to their indeterminate muscle growth, i.e., continued production of neonatal muscle fibers until death. However, the molecular mechanism(s) underlying this property is unknown. Here, we focused on the torafugu (Takifugu rubripes) myosin heavy chain gene, MYHM2528-1, which is specifically expressed in neonatal muscle fibers produced by indeterminate muscle growth. We examined the flanking region of MYHM2528-1 through an in vivo reporter assay using zebrafish (Danio rerio) and identified a 2100 bp 5'-flanking sequence that contained sufficient promoter activity to allow specific gene expression. The effects of enhanced promoter activity were observed at the outer region of the fast muscle and the dorsal edge of slow muscle in zebrafish larvae. At the juvenile stage, the promoter was specifically activated in small diameter muscle fibers scattered throughout fast muscle and in slow muscle near the septum separating slow and fast muscles. This spatio-temporal promoter activity overlapped with known myogenic zones involved in teleost indeterminate muscle growth. A deletion mutant analysis revealed that the -2100 to -600 bp 5'flanking sequence of MYHM2528-1 is essential for promoter activity. This region contains putative binding sites for several representative myogenesis-related transcription factors and nuclear factor of activated T-cell (NFAT), a transcription activator involved in regeneration of mammalian adult skeletal muscle. A significant reduction in the promoter activity of the MYHM2528-1 deletion constructs was observed in accordance with a reduction in the number of these binding sites, suggesting the involvement of specific transcription factors in indeterminate muscle growth.
    Matched MeSH terms: Promoter Regions, Genetic/genetics
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