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First Intron (first + intron)
Selected AbstractsOne of the duplicated matrix metalloproteinase-9 genes is expressed in regressing tail during anuran metamorphosisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 4 2006Kenta Fujimoto The drastic morphological changes of the tadpole are induced during the climax of anuran metamorphosis, when the concentration of endogenous thyroid hormone is maximal. The tadpole tail, which is twice as long as the body, shortens rapidly and disappears completely in several days. We isolated a cDNA clone, designated as Xl MMP-9TH, similar to the previously reported Xenopus laevis MMP-9 gene, and showed that their Xenopus tropicalis counterparts are located tandemly about 9 kb apart from each other in the genome. The Xenopus MMP-9TH gene was expressed in the regressing tail and gills and the remodeling intestine and central nervous system, and induced in thyroid hormone-treated tail-derived myoblastic cultured cells, while MMP-9 mRNA was detected in embryos. Three thyroid hormone response elements in the distal promoter and the first intron were involved in the upregulation of the Xl MMP-9TH gene by thyroid hormone in transient expression assays, and their relative positions are conserved between X. laevis and X. tropicalis promoters. These data strongly suggest that the MMP-9 gene was duplicated, and differentiated into two genes, one of which was specialized in a common ancestor of X. laevis and X. tropicalis to be expressed in degenerating and remodeling organs as a response to thyroid hormone during metamorphosis. [source] Role of ceramide kinase in peroxisome proliferator-activated receptor beta-induced cell survival of mouse keratinocytesFEBS JOURNAL, Issue 15 2008Kiyomi Tsuji Ceramide (Cer) is known to be a lipid mediator in apoptosis and to have an important role in cell fate, via control of intracellular Cer levels. Recently, ceramide kinase (CerK) was identified as an enzyme that converts Cer to ceramide 1-phosphate (C1P). We examined potential functions of CerK in the regulation of keratinocyte survival, and the possible involvement of peroxisome proliferator-activated receptor beta (PPAR,). PPAR, is known to be a nuclear receptor acting as a ligand-inducible transcription factor and has been implicated in the control of keratinocyte survival. In the mouse keratinocyte cell line SP1, serum starvation induced cell death and the accumulation of intracellular Cer, an apoptotic event. However, apoptosis was inhibited by activation of PPAR,. Interestingly, activation of PPAR, enhanced the mRNA expression of CerK and CerK activity. Furthermore, the cell survival effect of PPAR, was greatly diminished in keratinocytes isolated from CerK-null mice. Chromatin immunoprecipitation revealed that, in vivo, PPAR, binds to the CerK gene via a sequence located in the first intron. Electrophoretic mobility-shift assays confirmed that PPAR, associates with this sequence in vitro. These findings indicated that CerK gene expression was directly regulated by PPAR,. In conclusion, our results demonstrate that PPAR,-mediated upregulation of CerK gene expression is necessary for keratinocyte survival against serum starvation-induced apoptosis. [source] Level of MYC overexpression in pediatric Burkitt's lymphoma is strongly dependent on genomic breakpoint location within the MYC locusGENES, CHROMOSOMES AND CANCER, Issue 2 2004Monika Wilda Increased transcriptional activity of the MYC gene is a characteristic feature of Burkitt's lymphoma. Aberrant MYC expression is caused by (1) chromosomal translocation to one of the loci carrying an immunoglobulin gene, (2) mutation within the translocated allele, (3) loss of the block to transcription elongation, or (4) promoter shift. To investigate the influence of breakpoint locations within the MYC gene on MYC transcript levels, we determined both the precise genomic MYC/IGH breakpoints and the amount of MYC mRNA in 25 samples of pediatric Burkitt's lymphoma with translocation t(8;14)(q24;q32). Patients with breakpoints that were 5, from MYC exon 1 had significantly lower expression of MYC than did patients who had a breakpoint within exon 1 or intron 1 (P < 0.05 and 0.005, respectively). The highest mRNA level of MYC (1,006 copies per 100 copies ABL1) was detected in patients with loss of the first exon and transcription initiation from a cryptic P3 promoter within the first intron of the MYC gene. In contrast, there was no obvious correlation between breakpoint locations within the IgH locus and the amount of MYC mRNA. © 2004 Wiley-Liss, Inc. [source] Identification of a novel human tissue factor splice variant that is upregulated in tumor cells,INTERNATIONAL JOURNAL OF CANCER, Issue 7 2006Hitendra S. Chand Abstract Tissue factor (TF) is a transmembrane glycoprotein that serves as the prime initiator of blood coagulation and plays a critical role in thrombosis and hemostasis. In addition, a variety of tumor cells overexpress cell-surface TF, which appears to be important for tumor angiogenesis and metastasis. To elucidate the mechanism involved in the upregulation of TF in human tumor cells, a comprehensive analysis of TF mRNA from various normal and tumor cells was performed. The results of these studies indicate that, in addition to possessing a normal full-length TF transcript and minor levels of an alternatively spliced transcript known as alternatively-spliced tissue factor (asTF) (Bogdanov et al., Nat Med 2003;9:458,62), human tumor cells express additional full-length TF transcripts that are also generated by alternative splicing. Reverse transcriptase-polymerase chain reaction (RT-PCR) and 5,-rapid amplification of cDNA ends- (5,-RACE) based analyses of cytoplasmic RNA from normal and tumor cells revealed that there is alternative splicing of the first intron between exon I and exon II resulting in 2 additional TF transcripts. One of the transcripts has an extended exon I with inclusion of most of the first TF intron (955 bp), while the second transcript is formed by the insertion of a 495 bp sequence, referred to as exon IA, derived from an internal sequence of the first intron. The full length TF transcript with alternatively spliced novel exon IA, referred to as alternative exon 1A-tissue factor (TF-A), represented ,1% of the total TF transcripts in normal cells, but constituted 7,10% of the total TF transcript in tumor cells. Quantitative real-time RT-PCR analysis indicated that cultured human tumor cells contain 10,25-fold more copy numbers of TF-A in comparison to normal, untransformed cells. We propose that high-level expression of the novel TF-A transcript, preferentially in tumor cells, may have utility in the diagnosis and staging of a variety of solid tumors. © 2005 Wiley-Liss, Inc. [source] Polymorphisms of tumour necrosis factors A and B in breast cancerINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 1 2002K. S. Park Summary We assayed for germline single nucleotide polymorphisms (SNPs) in the TNFB and TNFA genes in patients with breast cancer. SNPs were observed in the first intron of TNFB (G/A) and at ,1031 (T/C), ,863 (C/A), ,857 (C/T) and ,308 (G/A) in the promoter region of TNFA from peripheral leucocytes in 95 breast cancer patients and 190 healthy subjects as controls. The TNFB*G/TNFB*G homozygote (23.2% vs. 5.8%, P= 0.001) was predominant in patients, while the TNFB*A/TNFB*A homozygote was less frequent in patients (34.7% vs. 46.3%, P = 0.041) than in the control subjects. Breast cancer was not associated with SNPs in the TNFA promoters. Although the TNFB SNP failed to associate with any clinicopathological parameter of breast cancer, a substantial difference in pathology among tumour stages for the ,857 SNP in TNFA was detected. These results indicate that TNFB has both tumorigenic and antitumorigenic capabilities depending on the genotype: the TNFB SNP TNFB*G/TNFB*G genotype gave an increased risk for breast cancer and that of TNFB*A/TNFB*A gave resistance to breast cancer (OR = 5.3395%; CI: 2.33,12.19). The results suggest that the TNFB*G allele plays some role in the tumorigenesis or activation of dormant tumour cells, but the TNFB*A allele induces some function(s) leading to the inhibition of tumorigenesis. [source] Variable number of tandem repeats in the growth hormone gene of Sparus aurata: association with growth and effect on gene transcriptionJOURNAL OF FISH BIOLOGY, Issue 2004R. Almuly The GH gene of Sparus aurata(saGH) contains variable number of tandem repeats (VNTR). The hyper-variable minisatellites in the first and third introns segregate in a Mendelian manner and exhibit numerous alleles. Analysis by PCR and sequencing of the two introns in several wild Sparidae species revealed comparable minisatellites with some variations. ,Zoo blot' with the first intron unit as a probe showed this sequence to be characteristic of several families from the Perciformes order. Unexpectedly, a similar minisatellite was found in the first intron of the GH gene in flounder, which belongs to a different order. Transfection of constructs containing a reporter gene and first intron of different length to four cell lines resulted in an inhibitory effect of the longer intron relative to the short intron. A (CA)n microsatellite (saGHpCA) is found in the GH promoter. A similar repeat at the same location is present in GH promoters of several other fish species. High variability (11 alleles) of the saGHpCA was found in a hatchery population. Full-sib family genotyping showed a Mendelian inheritance of these alleles. A significant association was found between allele distribution and body mass in large and average size fishes from a hatchery population. The intron minisatellites may serve as markers for hybrid population and parental assignment. Its presence in families and orders of the higher teleosts may help solving classification uncertainties. Their conservation and inhibitory effect suggest a biological role. The saGHpCA is correlated with growth and may be a good candidate for predicting growth performance. [source] The Caenorhabditis elegans lev-8 gene encodes a novel type of nicotinic acetylcholine receptor , subunitJOURNAL OF NEUROCHEMISTRY, Issue 1 2005Paula R. Towers Abstract We have cloned Caenorhabditis elegans lev-8 and demonstrated that it encodes a novel nicotinic acetylcholine receptor (nAChR) subunit (previously designated ACR-13), which has functional roles in body wall and uterine muscles as part of a levamisole-sensitive receptor. LEV-8 is an ,,subunit and is the first to be described from the ACR-8-like group, a new class of nAChR with atypical acetylcholine-binding site (loop C) and channel-lining motifs. A single base pair change in the first intron of lev-8 in lev-8(x15) mutants leads to alternative splicing and the introduction of a premature stop codon. lev-8(x15) worms are partially resistant to levamisole-induced egg laying and paralysis, phenotypes rescued by expression of the wild-type gene. lev-8(x15) worms also show reduced rates of pharyngeal pumping. Electrophysiological recordings from body wall muscle show that currents recorded in response to levamisole have reduced amplitude in lev-8(x15) compared with wild-type animals. Consistent with these phenotypic observations, green fluorescent protein fused to LEV-8 is expressed in body wall and uterine muscle, motor neurons and epithelial-derived socket cells. Thus, LEV-8 is a levamisole receptor subunit and exhibits the most diverse expression pattern of any invertebrate nAChR subunit studied to date. [source] Novel putative nonprotein-coding RNA gene from 11q14 displays decreased expression in brains of patients with schizophreniaJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2003Oxana O. Polesskaya Abstract A modified method of differential display was employed to identify a novel gene (named PSZA11q14), the expression of which was reduced in brains from patients with schizophrenia. Decreased expression of PSZA11q14 was identified initially in Brodmann's area (BA) 21 from a small group of patients with schizophrenia (n = 4) and normal controls (n = 6) and was confirmed subsequently using independent RT-PCR assay in BA 21, 22, and 9, and in hippocampus from a larger group of patients with schizophrenia (n = 36) and controls (n = 35). PSZA11q14 is located on chromosome 11q14, an area shown previously to co-segregate with schizophrenia and related disorders in several families. Decreased expression of PSZA11q14 in patients with schizophrenia and its location on 11q14 provide converging lines of evidence indicating that PSZA11q14 may be involved in at least some cases of schizophrenia. PSZA11q14 shows no significant homology with any known gene. It has no introns and produces two RNA transcripts of ,4.5 and ,7.0 kb. The largest open reading frame (ORF) in the PSZA11q14 transcripts may potentially encode for a short polypeptide of 71 amino acids. High frequency of rare codons, the short size of this ORF, and low homology with mouse sequences, however, indicate that PSZA11q14 may instead represent a novel member of a family of nonprotein-coding RNA genes that are not translated and that function at the RNA level. PSZA11q14 is located within the first intron of the DLG-2 gene and transcribed in the opposite direction to DLG-2. These results suggest that PSZA11q14 may be considered a candidate gene for schizophrenia acting as an antisense regulator of DLG-2, which controls assembling functional N -methyl- D -aspartate (NMDA) receptors. © 2003 Wiley-Liss, Inc. [source] Transcriptional regulatory defects in the first intron of Bruton's tyrosine kinasePEDIATRICS INTERNATIONAL, Issue 6 2008Dong-Min Shin Abstract Background: X-linked agammaglobulinemia (XLA), characterized by the early onset of recurrent bacterial infections, profound hypogammaglobulinemia, and a markedly diminished number of peripheral B lymphocytes, is caused by mutations in the Bruton's tyrosine kinase (BTK) gene. The >600 unique mutations identified to date include single base pair substitutions, small insertions or deletions, and gross deletions. A few cases, however, have been found to have no mutations in the coding region even with reduced BTK mRNA or protein expression. Mutations in intron 1 positions +5 (G,A) and +6 (T,G) of the BTK gene have been identified, and these changes were associated with reduced transcriptional activity. Methods: In the present study a novel mutation in intron 1 position +5 (G,T) was identified in a Japanese patient with XLA. The reporter constructs containing these mutations were made, and the reporter activities were measured using a luciferase assay. Results: All the mutant constructs were demonstrated to have reduced transcriptional activity. Conclusions: Positions +5 and +6 in intron 1 of the BTK gene are critical for transcriptional activity, and defects in these regions cause XLA. [source] Determination of incompatibility genotypes in almond using first and second intron consensus primers: detection of new S alleles and correction of reported S genotypesPLANT BREEDING, Issue 2 2005E. Ortega Abstract The work aimed to develop a reliable and convenient PCR approach for determining incompatibility S genotypes in almond. Initially, genomic DNAs of 24 accessions of known S genotype were amplified with novel consensus primers flanking the first and second introns of the S-RNase gene. The PCR products separated on agarose showed length polymorphisms and correlated well with the reference alleles S1-S23 and Sf. In addition, to improve discrimination between alleles of similar sizes, the same sets of primers but fluorescently labelled were used, and the products sized on an automated sequencer. These fluorescent primers were particularly informative in the case of the first intron, variation in the length of which has not been used previously for S genotyping in almond. Some reference alleles showed the same patterns with first and second intron primers, and others showed a microsatellite-like trace. Subsequently, the S genotypes of 26 cultivars not genotyped previously and of four of uncertain genotype were determined. An allele described in Australian work as putative S10 was shown to be a ,new' allele and ascribed to S24 and evidence of five more ,new'S alleles was found, for which the labels S25 -S29 are proposed. This PCR approach should be useful for genotyping in other Prunus crops. [source] Prenatal diagnosis for arginase deficiency by second-trimester fetal erythrocyte arginase assay and first-trimester ARG1 mutation analysisPRENATAL DIAGNOSIS, Issue 11 2004Stanley H. Korman Abstract Hyperargininemia is a progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. We diagnosed arginase deficiency in a three-year-old male child of first-cousin Palestinian Arab parents. Prenatal diagnosis of an unaffected fetus was achieved in the second trimester of a subsequent pregnancy by cordocentesis and analysis of arginase activity in fetal erythrocytes. ARG1 mutation analysis in the proband revealed homozygosity for a deletion of 10 753 bp extending from the first intron to beyond the poly (A) site of the gene. This is the first gross deletion in the ARG1 gene to be identified and the first mutation to be described in an arginase-deficient patient of this ethnic origin. The identification of the ARG1 deletion in this family enabled first-trimester prenatal diagnosis in a subsequent pregnancy by multiplex PCR analysis performed on chorionic villous DNA. Copyright © 2004 John Wiley & Sons, Ltd. [source] Changing transcriptional initiation sites and alternative 5,- and 3,-splice site selection of the first intron deploys Arabidopsis PROTEIN ISOASPARTYL METHYLTRANSFERASE2 variants to different subcellular compartmentsTHE PLANT JOURNAL, Issue 1 2008Randy D. Dinkins Summary Arabidopsis thaliana (L.) Heynh. possesses two PROTEIN-L-ISOASPARTATE METHYLTRANSFERASE (PIMT) genes encoding enzymes (EC 2.1.1.77) capable of converting uncoded l -isoaspartyl residues, arising spontaneously at l -asparaginyl and l -aspartyl sites in proteins, to l -aspartate. PIMT2 produces at least eight transcripts by using four transcriptional initiation sites (TIS; resulting in three different initiating methionines) and both 5,- and 3,-alternative splice site selection of the first intron. The transcripts produce mature proteins capable of converting l -isoaspartate to l -aspartate in small peptide substrates. PIMT:GFP fusion proteins generated a detectable signal in the nucleus. However, whether the protein was also detectable in the cytoplasm, endo-membrane system, chloroplasts, and/or mitochondria, depended on the transcript from which it was produced. On-blot-methylation of proteins, prior to the completion of germination, indicated that cruciferin subunits contain isoaspartate. The implications of using transcriptional mechanisms to expand a single gene's repertoire to protein variants capable of entry into the cell's various compartments are discussed in light of PIMT's presumed role in repairing the proteome. [source] The Arabidopsis FLC protein interacts directly in vivo with SOC1 and FT chromatin and is part of a high-molecular-weight protein complexTHE PLANT JOURNAL, Issue 2 2006Chris A. Helliwell Summary The Arabidopsis Flowering Locus C (FLC) protein is a repressor of flowering regulated by genes in the autonomous and vernalization pathways. Previous genetic and transgenic data have suggested that FLC acts by repressing expression of the floral integrator genes SOC1 and FT. We have taken an in vivo approach to determine whether the FLC protein interacts directly with potential DNA targets. Using chromatin immunoprecipitation, we have shown that FLC binds to a region of the first intron of FT that contains a putative CArG box, and have confirmed that FLC binds to a CArG box in the promoter of the SOC1 gene. MADS box proteins are thought to bind their DNA targets as dimers or higher-order multimers. We have shown that FLC is a component of a multimeric protein complex in vivo and that more than one FLC polypeptides can be present in the complex. [source] Molecular characterization, immunohistochemical localization and expression of a ribosomal protein L17 gene from Apis cerana ceranaARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2010Fei Meng Abstract Ribosomal protein L17 (RPL17) is a core protein of the large (60S) ribosomal subunit and plays an important role in protein synthesis. In this report, a RPL17 gene was isolated from Apis cerana cerana, designated as AccRPL17. Alignment analysis showed that AccRPL17 exhibits high homology to other known RPL17s. Moreover, genomic sequence analysis revealed that five exons are splitted by four introns, and the position of the first intron is comparatively conservative, being localized in the 5, untranslated region. Partial putative cis -acting elements related to development were also examined. Quantitative real-time PCR showed that the highest mRNA level was detected in larvae on the fifth day. Simultaneously, immunohistochemical localization showed that AccRPL17 is primarily concentrated in muscular tissues, stigma, body wall, and the surrounding of the eye in the fifth-instar larvae. Further studies suggested that AccRPL17 might be involved in responses to abiotic stresses. This is a report attempting to analyze the expression and distribution of RPL17 in A. cerana cerana. These results indicated that AccRPL17 might play an important role in insect development, and the importance of AccRPL17 in participating in abiotic stresses is discussed. © 2010 Wiley Periodicals, Inc. [source] Association study in a Sardinian sample between bipolar disorder and the nuclear receptor REV-ERB, gene, a critical component of the circadian clock systemBIPOLAR DISORDERS, Issue 2 2009Giovanni Severino Objective:, The aim of our study was to investigate the association between REV-ERB, gene (NR1D1) single nucleotide polymorphisms (SNPs) and bipolar disorder (BP) in a case-control sample of Sardinian ancestry and evaluate its effect on age at onset (AAO) of BP. Methods:, We genotyped SNPs rs12941497 (SNP1) and rs939347 (SNP2), located, respectively, in the first intron and in the 5,UTR region of the gene, in a sample comprised of 300 bipolar patients and 300 healthy controls of Sardinian ancestry. We also studied AAO by means of admixture analysis, obtaining a cutoff point of age 22 and then carrying out association analysis between the two AAO groups. Results:, In the case-control comparison, single marker analysis showed no association for any of the SNPs tested. Haplotype analysis showed a nominally significant association for two haplotypes of SNPs 1-2. Comparing the early- and later-onset groups, nominal association was found for SNP1. Haplotype analysis showed that one haplotype was nominally associated with the later-onset group. Conclusions:, Our results, indicating a nominal association of the REV-ERB, gene with BP, suggest a possible role of REV-ERB, in the pathogenesis of BP. Further investigation of larger independent samples and different populations is warranted. [source] Association of interferon-, +874A polymorphism with the risk of developing cervical cancer in north-Indian populationBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 12 2009R Gangwar Objective, Interferon gamma (IFN -,) is a pro-inflammatory cytokine playing a pivotal role in both innate and adaptive immune responses. A single nucleotide polymorphism located in the first intron of the human IFN-, gene can influence the secretion of cytokine. Therefore, we aimed to investigate the association of IFN-, T/A gene polymorphism with the risk of cervical cancer. Design, Case,control study. Setting, Uttar Pradesh State in India. Sample, Two hundred cases with histologically proven cancer of the cervix and healthy controls (n = 230), age and ethnicity matched were recruited in this study. Methods, Genotyping was performed for bi-allelic +874 (T/A) polymorphism of IFN-, by amplification refractory mutation system method. Main outcome measures, Low producer IFN-, +874 AA genotype was associated with high risk for cervical cancer, which further modulated the increased risk in tobacco users. Results,IFN-, AA genotype which is low producer of IFN-, was associated with increased risk of cervical cancer (OR = 2.43, P = 0.003). Allele A was at 1.54-fold increased risk of cervical cancer (OR=1.54, P = 0.002). The AA genotype showed statistically significant risk with high stage (III + IV) of cervical cancer (OR = 4.99, P = 0.001). In tobacco users, AA genotype showed significantly increased susceptibility to cervical cancer (OR = 5.08, P = 0.010). Conclusion, Variation in IFN-, +874 AA genotype because of ethnicity in north-Indian population may represent an important susceptibility biomarker for cervical cancer risk as well as other diseases and should be explored further. [source] Homozygosis for (12) CA repeats in the first intron of the human IFN- , gene is significantly associated with the risk of aplastic anaemia in Caucasian populationBRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2004Carlo Dufour Summary Interferon- , (IFN- ,) mediates the final damage of the stem cell compartment in Aplastic Anaemia (AA). Normal subjects homozygous for 12 (CA) repeats of polymorphism variable number of dinucleotide (CA) repeat (VNDR) in position 1349 of the IFN- , gene (IFNG) were shown to overproduce IFN- ,in vitro. We studied the distribution of polymorphism VNDR 1349 of IFNG in 67 Caucasian AA patients and in normal controls. Genotype (CA)12-12, (homozygosis for allele 2) and the single allele 12 were significantly more frequent (P = 0·005 and 0·004 respectively) in patients versus controls. The polymorphism was equally distributed in AA patients regardless of their response to immunosuppression. Homozygosity for 12 (CA) repeats of polymorphism VNDR 1349 of IFNG is strongly associated with the risk of AA in Caucasian subjects. [source] Paradoxical early glucocorticoid induction of stem cell factor (SCF) expression in inflammatory conditionsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2004Carla Alexandra Da Silva Stem cell factor (SCF) is a major growth factor for mast cells, promoting their differentiation and chemotaxis. Its expression is regulated by glucocorticoids in inflammatory conditions, showing an early increased protein expression, before the expected anti-inflammatory decrease (Da Silva et al., Br. J. Pharmacol. 2002:135,1634). We here evaluated the early kinetic of SCF expression regulated by interleukin (IL)-1,, budesonide and the combination of both in human lung fibroblasts in culture. Budesonide potentiated the IL-1, -enhanced expression of SCF mRNA (+103%) and protein (+98%) very shortly after treatment (at 30 min and 1 h, respectively). A gentle downregulation followed. This potentiating effect of budesonide was related to increased SCF mRNA stability and SCF gene transcription. Deletion of a ,B-like site that we identified in the first intron of the SCF gene, in a luciferase reporter system, abolished the potentiation by budesonide, as well as the effect of IL-1, alone, as compared to the wild-type construction activity. All budesonide-induced effects were glucocorticoid-receptor dependent, since they were reproduced by dexamethasone and blocked by RU486. IL-1,+budesonide did not affect the relative expression of the soluble and membrane-bound forms of SCF. In conclusion, our results clearly show that glucocorticoids act very early to adversely increase the expression of SCF mRNA and protein in the inflammatory conditions created by IL-1,, and that this effect involves increased mRNA stability and increased gene expression through activation of the NF- ,B-like responsive element. British Journal of Pharmacology (2004) 141, 75,84. doi:10.1038/sj.bjp.0705598 [source] Subcellular distribution of S100A4 and its transcriptional regulation under hypoxic conditions in gastric cancer cell line BGC823CANCER SCIENCE, Issue 5 2010Ruixiu Zhang It is well known that S100A4 is overexpressed in many tumors and involved in tumor invasion and metastasis. But the regualtion of it is ill understood. We previously found that hypoxia mimicking cobalt chloride (CoCl2) enhanced the mRNA and protein expressions of the S100A4 gene in the gastric cancer cell line BGC823. In this study we found that S100A4 also displayed increased expression in BGC823 cells after exposure to real hypoxia (2.5% O2) as that by CoCl2 treatment. Moreover, S100A4 protein showed different subcellular distribution under real hypoxia compared with that by CoCl2 treatment or in normoxic conditions. To investigate the underlying molecular mechanism by which hypoxia regulates the expression of S100A4, we analyzed the regulatory sequences of the genes by bioinformatics and found a putative hypoxia responsive element (HRE) motif in the first intron of S1004. Furthermore, luciferase reporter assay showed that it is responsive to hypoxia. Electrophoretic mobility shift assay and chromatin immunoprecipitation assays demonstrated that hypoxia-inducible factor 1 (HIF-1) binds to the functional HRE in vitro and in vivo. The results provide evidence that S100A4 is a hypoxia-inducible gene, whose transcription is stimulated at least partly through the interaction of HIF-1 and HRE located at +329 to +334 of S100A4. (Cancer Sci 2010; 101: 1141,1146) [source] Unraveling the genetics of exfoliation glaucomaACTA OPHTHALMOLOGICA, Issue 2008F JONASSON Purpose To give an account of our recent discovery (2007) of the association of lysyl oxidase like 1 (LOXL1) sequence variants and exfoliation glaucoma (XFG) as well as later replications in other populations. Methods We did a genome-wide association study on open angle glaucoma cases and controls using the Illumina 300 chip. This chip includes probes for 317.000 single , nucleotide polymorphisms (SNPs), that tag, as highly correlated surrogates about 80% of the 2.1 million known common SNPs in the Caucasian genome. For diagnosis of exfoliation syndrome a peripheral band or central shield of exfoliative material on the anterior lens capsule was required. Results When we had done 195 open angle glaucoma cases high genome wide significance was achieved on chromosome 15q24.1 an association later found to be confined to XFG only. This SNP (rs2165241T) was located in the first intron of the LOXL1 gene. We then added 11 correlated SNPs that are not on the Illumina chip and found that two non-synonymous variants in the first exon of LOXL1 can jointly account for all the observed association (R141L, OR 2.5; G153D, OR 20.1). Combined the variants explained 99% of the population attributable risk for exfoliation glaucoma. Conclusion These findings have now largely been confirmed in numerous American, Asian, Australian and European studies, and in all instances do these polymorphisms in the LOXL1 gene confer risk to XFG. LOXL1 is cross linking enzyme responsible for elastin polymer deposition in ocular tissue. The LOXL1 discovery is the first big hit in the search for genetic background for exfoliation glaucoma. These findings may soon influence monitoring of glaucoma suspects in the clinic targeting persons with the high risk haplotypes. [source] Novel mutations in the EXT1 gene in two consanguineous families affected with multiple hereditary exostoses (familial osteochondromatosis)CLINICAL GENETICS, Issue 2 2004M Faiyaz-Ul-Haque Multiple hereditary exostoses (HME) is an autosomal dominant developmental disorder exhibiting multiple osteocartilaginous bone tumors that generally arise near the ends of growing long bones. Here, we report two large consanguineous families from Pakistan, who display the typical features of HME. Affected individuals also show a previously unreported feature , bilateral overriding of single toes. Analysis using microsatellite markers for each of the known EXT loci, EXT1, EXT2, and EXT3 showed linkage to EXT1. In the first family, mutation analysis of the EXT1 gene revealed that affected individuals were heterozygous for an in-frame G-to-C transversion at the conserved splice donor site in intron 1. This mutation is predicted to disrupt splicing of the first intron and produce a frameshift that leads to a premature termination codon. In the second family, an insertion of an A in exon 8 is predicted to produce a frameshift at codon 555 followed by a premature termination, a further 10 codons downstream. In both families, an increased number of affected male subjects were observed. In affected females in family 2, phenotypic variability and incomplete penetrance were noted. [source] The effect of intron location on intron-mediated enhancement of gene expression in ArabidopsisTHE PLANT JOURNAL, Issue 5 2004Alan B. Rose Summary Introns are often required for full expression of genes in organisms as diverse as plants, insects, nematodes, yeast, and mammals. To explore the potential mechanisms of intron-mediated enhancement in Arabidopsis thaliana, the effect of varying the position of an intron was determined using a series of reporter gene fusions between TRYPTOPHAN BIOSYNTHESIS1 (TRP1) and GUS. Two introns that differ in the degree to which they stimulate expression were individually tested at six locations within coding sequences and two positions in the 3,-UTR. The ability of the first introns from both the TRP1 and POLYUBIQUITIN10 (UBQ10) genes to elevate mRNA accumulation in transgenic plants was found to decline with distance from the promoter, despite their being efficiently spliced from all coding sequence locations. Neither intron significantly enhanced mRNA accumulation when positioned 1.1 kb or more from the start of transcription. In addition, measurements of GUS enzyme activity revealed that both introns at all locations elevated GUS activity more than they enhanced mRNA accumulation. The stimulation mediated by two of four other introns tested at the position nearest the promoter was also greater at the level of GUS activity than mRNA accumulation. These findings support a model in which introns increase transcription and promote translation by two distinct mechanisms. [source] | ||||||||||||||||