Angiogenic induction was made to promote angiogenesis by differentiating stem cells towards endothelial cells. However, the stemness property of induced cells has not been revealed yet. Hence, we aim to evaluate the differential mRNA expression of stemness genes in human chorion-derived stem cells (CDSC) after being cultured in EDM50 comprised bFGF and VEGF. Results indicated that CDSC cultured in EMD50 expressed significantly higher mRNA level of Sox-2, FZD9, BST-1 and Nestin. In addition Oct-4, FGF-4 and ABCG-2 were also upregulated. Our finding suggested that CDSC after angiogenic induction enhanced its stem cell properties. This could be contributed for the mechanism of stem cell therapy in ischemic problem.
Psidium guajava wilt is known from South Africa, Malaysia and Taiwan. The fungus causing this disease, Myxosporium psidii, forms dry chains of conidia on surfaces of pseudoparenchymatous sporodochia, which develop in blisters on bark. Similar sporodochia are characteristic of Nalanthamala madreeya, the type species of Nalanthamala. Nalanthamala, therefore, is the appropriate anamorph genus for Myxosporium psidii, while Myxosporium is a nomen nudum (based on M. croceum). For M. psidii the combination Nalanthamala psidii is proposed. Nalanthamala psidii, the palm pathogen Gliocladium (Penicillium) vermoesenii, another undescribed anamorphic species from palm, two species of Rubrinectria and the persimmon pathogen Acremonium diospyri are monophyletic and belong to the Nectriaceae (Hypocreales) based on partial nuclear large subunit ribosomal DNA (LSU rDNA) analyses. Rubrinectria, therefore, is the teleomorph of Nalanthamala, in which the anamorphs are classified as N. vermoesenii, N. diospyri or Nalanthamala sp. Nalanthamala squamicola, the only other Nalanthamala species, has affinities with the Bionectriaceae and is excluded from this group. Rubrinectria/Nalanthamala species form dimorphic conidiophores and conidia in culture. Fusiform, cylindrical, or allantoid conidia arise in colorless liquid heads on acremonium-like conidiophores; ovoidal conidia with somewhat truncated ends arise in long, persistent, dry chains on penicillate conidiophores. No penicillate but irregularly branched conidiophores were observed in N. diospyri. Conidia of N. psidii that are held in chains are shorter than those of N. madreeya, of which no living material is available. Nalanthamala psidii and N. diospyri are pathogenic specifically to their hosts. They form pale yellow to pale orange or brownish orange colonies, respectively, and more or less white conidial masses. Most strains of Rubrinectria sp., Nalanthamala sp. and N. vermoesenii originate from palm hosts, form mostly greenish or olive-brown colonies and white-to-salmon conidial masses. They form a monophyletic clade to which Nalanthamala psidii and N. diospyri are related based on analyses of the internal transcribed spacer regions and 5.8S rDNA (ITS rDNA), LSU rDNA, and partial beta-tubulin gene. Few polymorphic sites in the ITS rDNA and beta-tubulin gene indicate that Nalanthamala psidii comprises two lineages, one of which has been detected only in South Africa.
Epstein-Barr virus (EBV) is a ubiquitous tumor-causing virus which infects more than 90% of the world population asymptomatically. Recent studies suggest that LMP-1, -2A and -2B cooperate in the tumorigenesis of EBV-associated epithelial cancers such as nasopharygeal carcinoma, oral and gastric cancer. In this study, LMPs were expressed in the HEK293T cell line to reveal their oncogenic mechanism via investigation on their involvement in the regulation of the cell cycle and genes that are involved. LMPs were expressed in HEK293T in single and co-expression manner. The transcription of cell cycle arrest genes were examined via real-time PCR. Cell cycle progression was examined via flow cytometry. 14-3-3σ and Reprimo were upregulated in all LMP-1 expressing cells. Moreover, cell cycle arrest at G(2)/M progression was detected in all LMP-1 expressing cells. Therefore, we conclude that LMP-1 may induce cell cycle arrest at G(2)/M progression via upregulation of 14-3-3σ and Reprimo.
The frequency of the HLA class II antigens/alleles (HLA-DR, DQ and DP) were studied in 70 Malaysian Chinese patients with systemic lupus erythematosus (SLE) to examine the contribution of these genes to disease susceptibility, their clinical expression and Immunological responses. This was done using modified PCR-RFLP technique. These samples were then compared with 66 ethnically matched controls. We found a strong association of the DQA1*0102 (p corr = 0.032, rr = 3.39), DQB1*0501 (p corr = 0.003, rr = 4.55), *0601 (p corr = 0.006, rr = 4.22) and DPB1* 0901(p corr = 0.02, rr = 4.58) with SLE. Clinically, we found a strong association of DR2 and DQA1*0301 with renal involvement and DQA1*0102 with alopecia. Immunologically, statistical analysis (Chi-square test ) showed a strong association of DQA1*0102 with anti-Ro/La antibodies while DQA1*0301 was observed to be strongly associated with antibodies to ds DNA. DQA1*0102 was found more frequently in those with a later disease onset (30 years of age or above). From these data we suggest that the HLA class II genes play a role in conferring disease susceptibility and clinical and immunological expression.
Study site: SLE clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Matched MeSH terms: Histocompatibility Antigens Class II/genetics; Autoantibodies/genetics*; Gene Frequency/genetics; HLA-DP Antigens/genetics; HLA-DQ Antigens/genetics; HLA-DR Antigens/genetics; Lupus Erythematosus, Systemic/genetics*; Genetic Predisposition to Disease/genetics; Asian Continental Ancestry Group/genetics*
Through the specific identification and direct targeting of cancer stem cells (CSCs), it is believed that a better treatment efficacy of cancer may be achieved. Hence, the present study aimed to identify a CSC subpopulation from adenocarcinoma cells (A549) as a model of non‑small cell lung cancer (NSCLC). Ιnitially, we sorted two subpopulations known as the triple‑positive (EpCAM+/CD166+/CD44+) and triple‑negative (EpCAM-/CD166-/CD44-) subpopulation using fluorescence-activated cell sorting (FACS). Sorted cells were subsequently evaluated for proliferation and chemotherapy-resistance using a viability assay and were further characterized for their clonal heterogeneity, self-renewal characteristics, cellular migration, alkaline dehydrogenase (ALDH) activity and the expression of stemness-related genes. According to our findings the triple‑positive subpopulation revealed significantly higher (P<0.01) proliferation activity, exhibited better clonogenicity, was mostly comprised of holoclones and had markedly bigger (P<0.001) spheroid formation indicating a better self-renewal capacity. A relatively higher resistance to both 5‑fluouracil and cisplatin with 80% expression of ALDH was observed in the triple‑positive subpopulation, compared to only 67% detected in the triple‑negative subpopulation indicated that high ALDH activity contributed to greater chemotherapy-resistance characteristics. Higher percentage of migrated cells was observed in the triple‑positive subpopulation with 56% cellular migration being detected, compared to only 19% in the triple‑negative subpopulation on day 2. This was similarly observed on day 3 in the triple‑positive subpopulation with 36% higher cellular migration compared to the triple‑negative subpopulation. Consistently, elevated levels of the stem cell genes such as REX1 and SSEA4 were also found in the triple‑positive subpopulation indicating that the subpopulation displayed a strong characteristic of pluripotency. In conclusion, our study revealed that the triple‑positive subpopulation demonstrated similar characteristics to CSCs compared to the triple‑negative subpopulation. It also confirmed the feasibility of using the triple‑positive (EpCAM+/CD166+/CD44+) marker as a novel candidate marker that may lead to the development of novel therapies targeting CSCs of NSCLC.
Imatinib mesylate is an anti‑neoplastic targeted chemotherapeutic agent, which can inhibit tyrosine kinase receptors, including BCR‑ABL, platelet‑derived growth factor receptors (PDGFRs) and c‑Kit. Cellular processes, including differentiation, proliferation and survival are regulated by these receptors. The present study aimed to evaluate the antiproliferative effects of imatinib mesylate, and its effects on apoptotic induction and cell cycle arrest in breast cancer cell lines. In addition, the study aimed to determine whether the effects of this drug were associated with the mRNA and protein expression levels of PDGFR‑β, c‑Kit, and their corresponding ligands PDGF‑BB and stem cell factor (SCF), which may potentially modulate cell survival and proliferation. To assess the antiproliferative effects of imatinib mesylate, an MTS assay was conducted following treatment of cells with 2‑10 µM imatinib mesylate for 96, 120 and 144 h; accordingly the half maximal inhibitory concentration of imatinib mesylate was calculated for each cell line. In addition, the proapoptotic effects and cytostatic activity of imatinib mesylate were investigated. To evaluate the expression of imatinib‑targeted genes, PDGFR‑β, c‑Kit, PDGF‑BB and SCF, under imatinib mesylate treatment, mRNA expression was detected using semi‑quantitative polymerase chain reaction and protein expression was detected by western blot analysis in ZR‑75‑1 and MDA‑MB‑231 breast carcinoma cell lines. Treatment with imatinib mesylate suppressed cell proliferation, which was accompanied by apoptotic induction and cell cycle arrest in the investigated cell lines. In addition, PDGFR‑β, PDGF‑BB, c‑Kit and SCF were expressed in both breast carcinoma cell lines; PDGFR‑β and c‑Kit, as imatinib targets, were downregulated in response to imatinib mesylate treatment. The present results revealed that at least two potential targets of imatinib mesylate were expressed in the two breast carcinoma cell lines studied. In conclusion, the antiproliferative, cytostatic and proapoptotic effects of imatinib mesylate may be the result of a reduction in the expression of c‑Kit and PDGFR tyrosine kinase receptors, thus resulting in suppression of the corresponding ligand PDGF‑BB. Therefore, imatinib mesylate may be considered a promising target therapy for the future treatment of breast cancer.
Noncoding repeat expansions cause various neuromuscular diseases, including myotonic dystrophies, fragile X tremor/ataxia syndrome, some spinocerebellar ataxias, amyotrophic lateral sclerosis and benign adult familial myoclonic epilepsies. Inspired by the striking similarities in the clinical and neuroimaging findings between neuronal intranuclear inclusion disease (NIID) and fragile X tremor/ataxia syndrome caused by noncoding CGG repeat expansions in FMR1, we directly searched for repeat expansion mutations and identified noncoding CGG repeat expansions in NBPF19 (NOTCH2NLC) as the causative mutations for NIID. Further prompted by the similarities in the clinical and neuroimaging findings with NIID, we identified similar noncoding CGG repeat expansions in two other diseases: oculopharyngeal myopathy with leukoencephalopathy and oculopharyngodistal myopathy, in LOC642361/NUTM2B-AS1 and LRP12, respectively. These findings expand our knowledge of the clinical spectra of diseases caused by expansions of the same repeat motif, and further highlight how directly searching for expanded repeats can help identify mutations underlying diseases.
Matched MeSH terms: Ataxia/genetics*; Fragile X Syndrome/genetics*; Muscular Dystrophies/genetics*; Tremor/genetics*; Neurodegenerative Diseases/genetics*; Trinucleotide Repeat Expansion/genetics*; Low Density Lipoprotein Receptor-Related Protein-1/genetics; Intranuclear Inclusion Bodies/genetics; Fragile X Mental Retardation Protein/genetics
RNA-binding proteins (RBPs) have been implicated as regulatory proteins involved in the post-transcriptional processes of gene expression in plants under various stress conditions. In this study, we report the cloning and characterization of a gene, designated as EgRBP42, encoding a member of the plant heterogeneous nuclear ribonucleoprotein (hnRNP)-like RBP family from oil palm (Elaeis guineensis Jacq.). EgRBP42 consists of two N-terminal RNA recognition motifs and a glycine-rich domain at the C-terminus. The upstream region of EgRBP42 has multiple light-responsive, stress-responsive regulatory elements and regulatory elements associated with flower development. Real-time RT-PCR analysis of EgRBP42 showed that EgRBP42 was expressed in oil palm tissues tested, including leaf, shoot apical meristem, root, female inflorescence, male inflorescence and mesocarp with the lowest transcript level in the roots. EgRBP42 protein interacted with transcripts associated with transcription, translation and stress responses using pull-down assay and electrophoretic mobility shift assay. The accumulation of EgRBP42 and its interacting transcripts were induced by abiotic stresses, including salinity, drought, submergence, cold and heat stresses in leaf discs. Collectively, the data suggested that EgRBP42 is a RBP, which responds to various abiotic stresses and could be advantageous for oil palm under stress conditions. Key message EgRBP42 may be involved in the post-transcriptional regulation of stress-related genes important for plant stress response and adaptation.
Sprouty-related protein-2 (Spred-2) is a negative regulator of extracellular signal-regulated kinases (ERK) pathway, which is important for cell proliferation, neuronal differentiation, plasticity and survival. Nevertheless, its general molecular characteristics such as gene expression patterns and potential role in neural repair in the brain remain unknown. Thus, this study aimed to characterise the expression of spred-2 in the zebrafish brain. Digoxigenin-in situ hybridization showed spred-2 mRNA-expressing cells were mainly seen in the proliferative zones such as the olfactory bulb, telencephalon, optic tectum, cerebellum, and the dorsal and ventral hypothalamus, and most of which were neuronal cells. To evaluate the potential role of spred-2 in neuro-regeneration, spred-2 gene expression was examined in the dorsal telencephalon followed by mechanical-lesion. Real-time PCR showed a significant reduction of spred-2 mRNA levels in the telencephalon on 1-day till 2-days post-lesion and gradually increased to normal levels as compared with intact. Furthermore, to confirm involvement of Spred-2 signalling in the cell proliferation after brain injury, double-labelling of spred-2 in-situ hybridization with immunofluorescence of BrdU and phosphorylated-ERK1/2 (p-ERK1/2), a downstream of Spred-2 was performed. Increase of BrdU and p-ERK1/2 immunoreactive cells suggest that a decrease in spred-2 after injury might associated with activation of the ERK pathway to stimulate cell proliferation in the adult zebrafish brain. The present study demonstrates the possible role of Spred-2 signalling in cell proliferative phase during the neural repair in the injured zebrafish brain.
Stem cells (SCs) are capable of self-renewal and multilineage differentiation. Human mesenchymal stem cells (MSCs) and haematopoietic stem cells (HSCs) which can be obtained from multiple sources, are suitable for application in regenerative medicine and transplant therapy. The aim of this review is to evaluate the potential of genomic and proteomic profiling analysis to identify the differentiation of MSCs and HSCs towards osteoblast and odontoblast lineages. In vitro differentiation towards both of these lineages can be induced using similar differentiation factors. Gene profiling cannot be utilised to confirm the lineages of these two types of differentiated cells. Differentiated cells of both lineages express most of the same markers. Most researchers have detected the expression of genes such as ALP, OCN, OPN, BMP2 and RUNX2 in osteoblasts and the expression of the DSPP gene in odontoblasts. Based on their cell-type specific protein profiles, various proteins are differentially expressed by osteoblasts and odontoblasts, except for vimentin and heterogeneous nuclear ribonucleoprotein C, which are expressed in both cell types, and LOXL2 protein, which is expressed only in odontoblasts.
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.
The High-Risk Human Papillomaviruses (HR-HPVs) 16 and 18 are known to cause cervical cancer, which is primarily attributed to E6 and E7 oncoproteins. In addition, recent studies have focused on the vital role of the p130 pocket protein as an oncosuppressor to limit the expression of E2F transcription factors required for cell cycle progression. In view of this, the current study was conducted to investigate the mechanism by which transfection with HPV16/18 E7 leads to the deregulation of the host cell cycle, altering the localisation of p130, and expression of differentiation genes in Human Keratinocytes (HaCaT) cells. Co-immunoprecipitation, Western blot analysis, immunofluorescence microscopy, flow cytometry, quantitative-Polymerase Chain Reaction (qPCR), and the inhibition of p130 by MG132 inhibitor were employed to investigate the loss of p130 and its disruption in HPV 16/18 E7-transfected HaCaT cells. The HPV16- and HPV18-transformed cells, known as CaSki and HeLa, respectively, were also used to complement the ectopic expressions of E7 in HaCaT cells. Normal keratinocytes displayed higher level of p130 expression than HPV-transformed cells. In addition, the immunofluorescence analysis revealed that both HPV 16/18 E7-transfected HaCaT and HPV-transformed cells exhibited higher level of cytoplasmic p130 compared to nuclear p130. A significant increase in the number of S/G2 phase cells in HPV-transformed cells was also recorded since E7 has been shown to stimulate proliferation through the deactivation of Retinoblastoma Protein (pRB)-dependent G1/S checkpoint. Furthermore, the findings recorded the down-regulation of keratinocyte differentiation markers, namely p130, keratin10, and involucrin. The proteasomal degradation of the exported p130 confirmed the cellular localisation pattern of p130, which was commonly observed in cancerous cells. The findings provide strong evidence that the localisation of nuclear p130 nuclear was disrupted by HPV16/18 E7 led to the deregulation of the cell cycle and the impairment of cellular differentiation ultimately lead to cellular transformation.
Lignification of the plant cell wall could serve as the first line of defense against pathogen attack, but the molecular mechanisms of virulence and disease between oil palm and Ganoderma boninense are poorly understood. This study presents the biochemical, histochemical, enzymology and gene expression evidences of enhanced lignin biosynthesis in young oil palm as a response to G. boninense (GBLS strain). Comparative studies with control (T1), wounded (T2) and infected (T3) oil palm plantlets showed significant accumulation of total lignin content and monolignol derivatives (syringaldehyde and vanillin). These derivatives were deposited on the epidermal cell wall of infected plants. Moreover, substantial differences were detected in the activities of enzyme and relative expressions of genes encoding phenylalanine ammonia lyase (EC 4.3.1.24), cinnamate 4-hydroxylase (EC 1.14.13.11), caffeic acid O-methyltransferase (EC 2.1.1.68) and cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.195). These enzymes are key intermediates dedicated to the biosynthesis of lignin monomers, the guaicyl (G), syringyl (S) and ρ-hydroxyphenyl (H) subunits. Results confirmed an early, biphasic and transient positive induction of all gene intermediates, except for CAD enzyme activities. These differences were visualized by anatomical and metabolic changes in the profile of lignin in the oil palm plantlets such as low G lignin, indicating a potential mechanism for enhanced susceptibility toward G. boninense infection.
Multiple Sclerosis (MS) is the most common autoimmune demyelinating disease of the Central Nervous System (CNS). It is a multifactorial disease which develops in an immune-mediated way under the influences of both genetic and environmental factors. Demyelination is observed in the brain and spinal cord leading to neuro-axonal damage in patients with MS. Due to the infiltration of different immune cells such as T-cells, B-cells, monocytes and macrophages, focal lesions are observed in MS. Currently available medications treating MS are mainly based on two strategies; i) to ease specific symptoms or ii) to reduce disease progression. However, these medications tend to induce different adverse effects with limited therapeutic efficacy due to the protective function of the blood-brain barrier. Therefore, researchers have been working for the last four decades to discover better solutions by introducing gene therapy approaches in treating MS generally by following three strategies, i) prevention of specific symptoms, ii) halt or reverse disease progression and iii) heal CNS damage by promoting remyelination and axonal repair. In last two decades, there have been some remarkable successes of gene therapy approaches on the experimental mice model of MS - experimental autoimmune encephalomyelitis (EAE) which suggests that it is not far that the gene therapy approaches would start in human subjects ensuring the highest levels of safety and efficacy. In this review, we summarised the gene therapy approaches attempted in different animal models towards treating MS.
The incidence of Alzheimer's disease, particularly in developing countries, is expected to increase exponentially as the population ages. Continuing research in this area is essential in order to better understand this disease and develop strategies for treatment and prevention. Genome-wide association studies have identified several loci as genetic risk factors of AD aside from apolipoprotein E such as bridging integrator (BIN1), clusterin (CLU), ATP-binding cassette sub-family A member 7 (ABCA7), complement receptor 1 (CR1) and phosphatidylinositol binding clathrin assembly protein (PICALM). However genetic research in developing countries is often limited by lack of funding and expertise. This study therefore developed and validated a simple, cost effective polymerase chain reaction based technique to determine these single nucleotide polymorphisms.
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: Breast Neoplasms/genetics*; Chromosomes, Human, Pair 5/genetics*; Enhancer Elements, Genetic/genetics; Haplotypes/genetics; Promoter Regions, Genetic/genetics; Genetic Predisposition to Disease/genetics*; Polymorphism, Single Nucleotide/genetics*; Quantitative Trait Loci/genetics; Fibroblast Growth Factor 10/genetics*
We have systematically analyzed beta-thalassemia genes using polymerase chain reaction-related techniques, dot-blot hybridization with oligonucleotide probes, allele specific-polymerase chain reaction, and sequencing of amplified DNA fragments from 41 unrelated patients, including 37 beta-thalassemia homozygotes, three with beta-thalassemia/Hb E, and one with beta-thalassemia/Hb S. Four different beta-thalassemia mutations were detected in 78 alleles. These are the IVS-I-5 (G-->C), codon 30 (AGG-->ACG) [also indicated as IVS-I (-1)], IVS-I-1 (G-->A), and codons 41/42 (-TTCT) mutations. The distribution of the beta-thalassemia mutations in the Maldives is 58 alleles (74.3%) with the IVS-I-5 (G-->C) mutation, 12 (15.4%) with the codon 30 (AGG-->ACG) mutation, seven (9%) with the IVS-I-1 (G-->A) mutation, and one with the codons 41/42 (-TTCT) mutation. The first three mutations account for 98.7% of the total number of beta-thalassemia chromosomes studied. These mutations are clustered in the region spanning 6 bp around the junction of exon 1 and the first intervening sequence of the beta-globin gene. These observations have significant implications for setting up a thalassemia prevention and control program in the Maldives. Analysis of haplotypes and frameworks of chromosomes bearing each beta-thalassemia mutation suggested that the origin and spread of these mutations were reflected by the historical record.
Integrin alpha M (ITGAM; CD11b) is a component of the macrophage-1 antigen complex, which mediates leukocyte adhesion, migration and phagocytosis as part of the immune system. We previously identified a missense polymorphism, rs1143679 (R77H), strongly associated with systemic lupus erythematosus (SLE). However, the molecular mechanisms of this variant are incompletely understood. A meta-analysis of published and novel data on 28 439 individuals with European, African, Hispanic and Asian ancestries reinforces genetic association between rs1143679 and SLE [Pmeta = 3.60 × 10(-90), odds ratio (OR) = 1.76]. Since rs1143679 is in the most active region of chromatin regulation and transcription factor binding in ITGAM, we quantitated ITGAM RNA and surface protein levels in monocytes from patients with each rs1143679 genotype. We observed that transcript levels significantly decreased for the risk allele ('A') relative to the non-risk allele ('G'), in a dose-dependent fashion: ('AA' < 'AG' < 'GG'). CD11b protein levels in patients' monocytes were directly correlated with RNA levels. Strikingly, heterozygous individuals express much lower (average 10- to 15-fold reduction) amounts of the 'A' transcript than 'G' transcript. We found that the non-risk sequence surrounding rs1143679 exhibits transcriptional enhancer activity in vivo and binds to Ku70/80, NFKB1 and EBF1 in vitro, functions that are significantly reduced with the risk allele. Mutant CD11b protein shows significantly reduced binding to fibrinogen and vitronectin, relative to non-risk, both in purified protein and in cellular models. This two-pronged contribution (nucleic acid- and protein-level) of the rs1143679 risk allele to decreasing ITGAM activity provides insight into the molecular mechanisms of its potent association with SLE.
CYP2C9 enzyme contributes to the metabolism of several pharmaceuticals and xenobiotics and yet displays large person-to-person and interethnic variation. Understanding the mechanisms of CYP2C9 variation is thus of immense importance for personalized medicine and rational therapeutics. A genetic variant of P450 (cytochrome) oxidoreductase (POR), a CYP450 redox partner, is reported to influence CYP2C9 metabolic activity in vitro. We investigated the impact of a common variant, POR*28, on CYP2C9 metabolic activity in humans. 148 healthy Swedish and 146 healthy Korean volunteers were genotyped for known CYP2C9 defective variant alleles (CYP2C9*2, *3). The CYP2C9 phenotype was determined using a single oral dose of 50 mg losartan. Excluding oral contraceptive (OC) users and carriers of 2C9*2 and *3 alleles, 117 Korean and 65 Swedish were genotyped for POR*5, *13 and *28 using Taqman assays. The urinary losartan to its metabolite E-3174 metabolic ratio (MR) was used as an index of CYP2C9 metabolic activity. The allele frequency of the POR*28 variant allele in Swedes and Koreans was 29% and 44%, respectively. POR*5 and *13 were absent in both study populations. Considering the CYP2C9*1/*1 genotypes only, the CYP2C9 metabolic activity was 1.40-fold higher in carriers of POR*28 allele than non-carriers among Swedes (p = 0.02). By contrast, no influence of the POR*28 on CYP2C9 activity was found in Koreans (p = 0.68). The multivariate analysis showed that ethnicity, POR genotype, and smoking were strong predictors of CYP2C9 MR (p < 0.05). This is the first report to implicate the importance of POR*28 genetic variation for CYP2C9 metabolic activity in humans. These findings contribute to current efforts for global personalized medicine and using medicines by taking into account pharmacogenetic and phenotypic variations.
Matched MeSH terms: Cytochrome P-450 Enzyme System/genetics*; European Continental Ancestry Group/genetics*; Asian Continental Ancestry Group/genetics*; Cytochrome P-450 CYP2C9/genetics*
Pyrethrins are natural insecticides, which accumulate to high concentrations in pyrethrum (Chrysanthemum cinerariaefolium) flowers. Synthetic pyrethroids are more stable, more efficacious and cheaper, but contemporary requirements for safe and environmentally friendly pesticides encourage a return to the use of natural pyrethrins, and this would be favoured by development of an efficient route to their production by microbial fermentation. The biosynthesis of pyrethrins involves ester linkage between an acid moiety (chrysanthemoyl or pyrethroyl, synthesised via the mevalonic acid pathway from glucose), and an alcohol (pyrethrolone). Pyrethrolone is generated from 3-oxo-2-(2'-pentenyl)-cyclopentane-1-octanoic acid, which originates from α-linolenic acid via the jasmonic acid biosynthetic cascade. The first four genes in this cascade, encoding lipoxygenase 2, allene-oxide synthase, allene-oxide cyclase 2 and 12-oxophytodienoic acid reductase 3, were amplified from an Arabidopsis thaliana cDNA library, cloned in a purpose-built fungal multigene expression vector and expressed in Aspergillus oryzae. HPLC-MS analysis of the transgenic fungus homogenate gave good evidence for the presence of 3-oxo-2-(2'-pentenyl)-cyclopentane-1-octanoic acid.