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Publication
Journal: Biochemical and Biophysical Research Communications
September/16/1974
Publication
Journal: Nucleic Acids Research
August/8/2011
Abstract
In pre-mRNA splicing, a conserved AG/G at the 3'-splice site is recognized by U2AF(35). A disease-causing mutation abrogating the G nucleotide at the first position of an exon (E(+1)) causes exon skipping in GH1, FECH and EYA1, but not in LPL or HEXA. Knockdown of U2AF(35) enhanced exon skipping in GH1 and FECH. RNA-EMSA revealed that wild-type FECH requires U2AF(35) but wild-type LPL does not. A series of artificial mutations in the polypyrimidine tracts of GH1, FECH, EYA1, LPL and HEXA disclosed that a stretch of at least 10-15 pyrimidines is required to ensure normal splicing in the presence of a mutation at E(+1). Analysis of nine other disease-causing mutations at E(+1) detected five splicing mutations. Our studies suggest that a mutation at the AG-dependent 3'-splice site that requires U2AF(35) for spliceosome assembly causes exon skipping, whereas one at the AG-independent 3'-splice site that does not require U2AF(35) gives rise to normal splicing. The AG-dependence of the 3'-splice site that we analyzed in disease-causing mutations at E(+1) potentially helps identify yet unrecognized splicing mutations at E(+1).
Publication
Journal: Journal of Biological Chemistry
October/19/1977
Publication
Journal: Enzyme and Microbial Technology
April/8/2012
Abstract
The gene bglU encoding a cold-adapted β-glucosidase (BglU) was cloned from Micrococcus antarcticus. Sequence analysis revealed that the bglU contained an open reading frame of 1419 bp and encoded a protein of 472 amino acid residues. Based on its putative catalytic domains, BglU was classified as a member of the glycosyl hydrolase family 1 (GH1). BglU possessed lower arginine content and Arg/(Arg+Lys) ratio than mesophilic GH1 β-glucosidases. Recombinant BglU was purified with Ni2+ affinity chromatography and subjected to enzymatic characterization. SDS-PAGE and native staining showed that it was a monomeric protein with an apparent molecular mass of 48 kDa. BglU was particularly thermolabile since its half-life time was only 30 min at 30°C and it exhibited maximal activity at 25°C and pH 6.5. Recombinant BglU could hydrolyze a wide range of aryl-β-glucosides and β-linked oligosaccharides with highest activity towards cellobiose and then p-nitrophenyl-β-d-glucopyranoside (pNPG). Under the optimal conditions with pNPG as substrate, the K(m) and k(cat) were 7 mmol/L and 7.85 × 103/s, respectively. This is the first report of cloning and characterization of a cold-adapted β-glucosidase belonging to GH1 from a psychrotolerant bacterium.
Publication
Journal: Human Molecular Genetics
October/3/1993
Abstract
Malignant hyperthermia (MH) is a potentially lethal pharmacogenetic disease with autosomal dominant inheritance triggered by exposure to commonly used inhalational anaesthetics or depolarising muscle relaxants. A MHS locus has been identified on human chromosome 19q12-q13.2 and the gene for the skeletal muscle calcium release channel of sarcoplasmic reticulum (ryanodine receptor) (RYR1) is considered a candidate for the molecular defect. However, MH has been shown to be genetically heterogeneous, and in the ensuing search for other MHS genes, a locus on chromosome 17q has been proposed, and the gene for the adult muscle sodium channel (SCN4A) was suggested as a candidate. We performed linkage studies using polymorphic microsatellite markers for subunits of the skeletal muscle dihydropyridine (DHP) receptor, CACNL1A3 mapped to chromosome 1q, as well as C-ACNLB1 and CACNLG, the latter two localised on chromosome 17q11.2-q24 in proximity to the proposed MHS2 and the SCN4A loci, and we also included markers for the loci D17S250, D17S579, NM23 (NME1), GH1, and SCN4A from that region. Our results exclude the alpha 1, beta 1 and gamma subunit of the DHP receptor as well as the SCN4A locus from that region. Our results exclude the alpha 1, beta 1, and gamma subunit of the DHP receptor as well as the SCN4A locus as candidates for the molecular defect in MHS for these pedigrees where also the RYR1 on chromosome 19q13.1 has been excluded. A multipoint analysis excludes the disease from the entire 84 cM interval containing the proposed MHS locus on chromosome 17q.(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: Molecular and Cellular Endocrinology
August/19/1999
Abstract
Growth hormone (GH) gene expression has been examined in control and transgenic coho salmon containing a transgene comprised of the sockeye salmon GH1 gene under the control of the MT-B promoter from the same species. This transgene dramatically enhances the growth of salmonids, and raises serum GH levels some forty-fold. Transcript levels from this transgene were detected by RT-PCR using construct-specific GH primers in all tissues examined (liver, kidney, skin, intestine, stomach, muscle, spleen, pyloric caeca), and ranged from 0.1 - 9.4 pg/50 microg total RNA in different tissues as estimated by dot blot analysis. Interestingly, GH gene expression was also observed in intestine of control coho salmon by RT-PCR capable of detecting host and transgene transcripts using general primers. Sequence analysis of the intestinal GH mRNA from controls indicated it was derived from the coho GH2 gene. GH mRNA abundance analyzed by northern analysis indicates lower levels are found in large (400-500 g) than small transgenic salmon (20-21 g). No molecular evidence for transgene expression was obtained in tissues from transgenic fry, despite an obvious increase in size relative to control siblings, suggesting very low levels of transgene expression early in development. GH mRNA levels (per microg RNA) were also examined in the pituitary gland, and were found to be significantly lower (P < 0.01) in transgenic coho compared to nontransgenic animals of the same size. Pituitary glands of transgenic animals were also smaller than control animals of the same size, and pituitary size, expressed as a proportion of body weight, decreased with body size in transgenic but not control animals. These results imply that pituitary GH expression is regulated by negative feed-back controls as occurs in other vertebrate systems. GH mRNA was examined in pituitary glands by whole-mount in situ hybridization, and, whereas overall levels appeared reduced in transgenic animals, the site of hybridization did not differ between transgenic and control glands.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
September/6/1988
Abstract
Crossover sites resulting from unequal recombination within the human growth hormone (GH) gene cluster that cause GH1 gene deletions and isolated GH deficiency type 1A were localized in nine patients. In eight unrelated subjects homozygous for 6.7-kilobase (kb) deletions, the breakpoints are within two blocks of highly homologous DNA sequences that lie 5' and 3' to the GH1 gene. In seven of these eight cases, the breakpoints map within a 1250-base-pair (bp) region composed of 300-bp Alu sequences of 86% homology and flanking non-Alu sequences that are 600 and 300 bp in length and are of 96% and 88% homology, respectively. In the eighth patient, the breakpoints are 5' to these Alu repeats and are most likely within a 700-bp region of 96% homologous DNA sequences. In the ninth patient homozygous for a 7.6-kb deletion, the breakpoints are contained within a 29-bp perfect repeat lying 5' to GH1 and the human chorionic somatomammotropin pseudogene (CSHP1). Together, these results indicate that the presence of highly homologous DNA sequences flanking GH1 predispose to recurrent unequal recombinational events presumably through chromosomal misalignment.
Publication
Journal: Science
February/20/1991
Abstract
Familial growth hormone deficiency type 1A is an autosomal recessive disease caused by deletion of both growth hormone-1 (GH1) alleles. Ten patients from heterogeneous geographic origins showed differences in restriction fragment length polymorphism haplotypes in nondeleted regions that flanked GH1, suggesting that these deletions arose from independent unequal recombination events. Deoxyribonucleic acid (DNA) samples from nine of ten patients showed that crossovers occurred within 99% homologous, 594-base pair (bp) segments that flanked GH1. A DNA sample from one patient indicated that the crossover occurred within 454-bp segments that flanked GH1 and contained 274-bp repeats that are 98% homologous. Although Alu repeats, which are frequent sites of recombination, are adjacent to GH1, they were not involved in any of the recombination events studied. These results suggest that length and degree of DNA sequence homology are important in defining recombination sites that resulted in GH1 deletions.
Publication
Journal: Journal of Biological Chemistry
February/14/1985
Abstract
Glucocorticoid-receptor activation in GH1 cells results from the conversion of a 10 S oligomeric cytosolic form to a 4-5 S nuclear-binding species (Raaka, B. M., and Samuels, H. H. (1983) J. Biol. Chem. 258, 417-425). In this study, we report that triamcinolone acetonide (9 alpha-fluoro-11 beta, 16 alpha, 17 alpha, 21-tetrahydroxypregna-1,4-diene-3,20-dione 16,17-acetonide) elicits a time- and dose-dependent reduction of total-cell (nuclear + cytoplasmic) receptor. The mechanism of receptor regulation was studied by dense amino acid labeling of receptor using media containing 2H, 13C, and 15N-labeled amino acids. Total cell receptor was extracted with 0.4 M KCl and newly synthesized dense receptor was separated from pre-existing receptor of normal density by centrifugation in gradients of 15-30% sucrose (w/v) in D2O. Receptor levels in cells grown without [3H]triamcinolone acetonide was 260 +/- 19 fmol/100 micrograms of DNA (16,000 molecules/cell), and, with 10 nM [3H]triamcinolone acetonide, this decreased to 130 +/- 14 fmol/100 micrograms of DNA after 30 h. Receptor half-life was 19 +/- 1.9 h in the absence and 9.5 +/- 0.3 h in the presence of triamcinolone acetonide and accounted for the decrease in steady-state receptor levels. Receptor synthesis was 9.7 +/- 0.3 fmol/100 micrograms of DNA/h (580 molecules/cell/h) both in the presence and absence of 10 nM [3H]triamcinolone acetonide. Triamcinolone acetonide reduced the half-life in proportion to the extent of receptor occupancy and activation. During the approach to steady-state conditions, 10 nM [3H]triamcinolone acetonide shortened receptor half-life almost immediately to the value in cells grown with [3H]triamcinolone acetonide for 24 h or longer. Cycloheximide did not prevent the triamcinolone acetonide-mediated decrease in receptor half-life and the shortening of receptor half-life is rapidly reversed by removal of hormone. These studies support a model of receptor regulation in which triamcinolone acetonide converts the unactivated 10 S receptor to the activated 4-5 S form which is degraded at an increased rate by the cell.
Publication
Journal: Applied Microbiology and Biotechnology
November/24/2014
Abstract
Saccharomyces cerevisiae can be engineered to ferment cellodextrins produced by cellulases as a product of cellulose hydrolysis. Direct fermentation of cellodextrins instead of glucose is advantageous because glucose inhibits cellulase activity and represses the fermentation of non-glucose sugars present in cellulosic hydrolyzates. To facilitate cellodextrin utilization by S. cerevisiae, a fungal cellodextrin-utilizing pathway from Neurospora crassa consisting of a cellodextrin transporter and a cellodextrin hydrolase has been introduced into S. cerevisiae. Two cellodextrin transporters (CDT-1 and CDT-2) were previously identified in N. crassa, but their kinetic properties and efficiency for cellobiose fermentation have not been studied in detail. In this study, CDT-1 and CDT-2, which are hypothesized to transport cellodextrin with distinct mechanisms, were introduced into S. cerevisiae along with an intracellular β-glucosidase (GH1-1). Cellobiose transport assays with the resulting strains indicated that CDT-1 is a proton symporter while CDT-2 is a simple facilitator. A strain expressing CDT-1 and GH1-1 (DCDT-1G) showed faster cellobiose fermentation than the strain expressing CDT-2 and GH1-1 (DCDT-2G) under various culture conditions with different medium compositions and aeration levels. While CDT-2 is expected to have energetic benefits, the expression levels and kinetic properties of CDT-1 in S. cerevisiae appears to be optimum for cellobiose fermentation. These results suggest CDT-1 is a more effective cellobiose transporter than CDT-2 for engineering S. cerevisiae to ferment cellobiose.
Publication
Journal: Carcinogenesis
October/15/2006
Abstract
The regulation of growth hormone 1 (GH1) and insulin-like-growth factor-1 (IGF-1) release is under the influence of three pituitary hormones [growth hormone releasing hormone (GHRH), ghrelin (GHRL) and somatostatin (SST)], which act in an autocrine/paracrine fashion in the breast. By binding to their respective receptors, they control cell proliferation, differentiation and apoptosis in a GH1/IGF-1-dependent manner. We investigated single nucleotide polymorphisms (SNPs) in the GHRH, GHRHR, GHRL, GHSR, SST and SSTR2 gene regions in a Polish and a German cohort of 798 breast cancer cases and 1011 controls. Our study revealed an association of a novel TC repeat polymorphism in the SST promoter with a decreased breast cancer risk in the Polish study population [odds ratio (OR), 0.65; 95% confidence interval (CI), 0.44-0.96]. The closely linked SNP IVS1 A+46G showed the same trend. For both polymorphisms the association was stronger in women above the age of 50 (OR, 0.33; 95% CI, 0.14-0.76 and OR, 0.39; 95% CI, 0.18-0.87, respectively). The protective effect of these polymorphisms was confirmed in a haplotype analysis among women above 50 years of age and carrying the two variant alleles (OR, 0.37; 95% CI, 0.17-0.80). In the independent German population, we observed slightly decreased ORs among women above the age of 50 years. In the SSTR2 gene, carriers of the promoter 21/21 TG repeat genotype were at a decreased breast cancer risk (OR, 0.62; 95% CI, 0.41-0.94) compared to carriers of the other genotypes in the Polish population. Furthermore, we identified a protective effect of the GHRHR C-261T SNP in both populations (joint analysis CT+TT versus CC: OR, 0.80; 95% CI, 0.65-0.99). This effect was carried by a haplotype containing the protective allele. Thus, our study concludes a possible protective influence of distinct polymorphisms in genes involved in GH1 release on breast cancer risk.
Publication
Journal: Breast Cancer Research and Treatment
October/14/2007
Abstract
The growth hormone 1/insulin-like growth factor-1 (GH1/IGF-1) axis plays an essential role in the development of the breast by regulating cell proliferation, differentiation and apoptosis. Imbalances within this axis lead to an aberrant signalling and recent research has focussed on the overexpression of these growth factors and their involvement in breast cancer development. The increased understanding of the molecular mechanisms and signalling pathways connected to the GH1/IGF-1 axis has provided important insights into aetiology, prevention and therapy for breast cancer. However, to identify the contribution of the GH1/IGF-1 signalling pathway to cancer risk still remains a challenge since the results of various studies are controversial. Here, we discuss the influence of low-penetrance polymorphisms in the genes along the GH1/IGF-1 axis and their impact on hormone levels and cancer risk, especially breast cancer. We point out what is known about the effects of the variants and show how the interaction of genetic variants affects breast cancer risk.
Publication
Journal: Journal of Molecular Biology
September/17/1987
Abstract
Phase-sensitive two-dimensional nuclear magnetic resonance (n.m.r.) experiments have been used to obtain extensive proton resonance assignments for the carbon monoxide complex of sperm whale myoglobin. Multiple quantum experiments were particularly important in the assignment procedure. The assignments are the most complete yet reported for a protein of such high molecular weight (approximately 18,000) and make possible new and comprehensive studies of the structure and dynamics of carbonmonoxymyoglobin in solution. Assignments for seven of the histidine residues are reported, including the critical proximal and distal histidines. Most of these are at variance with the assignments already in the literature. The present n.m.r. data indicate that histidines 24 (B5) and 119 (GH1) are hydrogen bonded to each other and, in contrast to neutron diffraction data, show that His24 does not protonate at pH greater than 5. The aromatic rings of all the phenylalanine and tyrosine residues undergo rapid flips about the ring axis. The side-chains of Leu89 (F4) and Phe138 (H15), which border a large hydrophobic cavity, are particularly mobile.
Publication
Journal: Journal of Biological Chemistry
February/13/1983
Abstract
The glucocorticoid receptor in GH1 cells cultured without glucocorticoids and harvested in hypotonic buffer is primarily a cytosolic protein with a sedimentation coefficient of 10 S in low salt gradients. In gradients containing 0.4 M KCl, the receptor sediments at 3.5 S. Following incubation of cells for various times in culture medium containing dense amino acids, discrete peaks of newly synthesized dense receptor and normal density 3.5 S receptor are resolved in salt-containing gradients. The half-life of the 3.5 S receptor is 9.5 h. In contrast, the 10 S receptor gradually becomes more dense as the time of incubation of cells with dense medium increases and discrete normal and dense receptor peaks are not resolved in sucrose gradients. These results suggest that the 10 S receptor is an oligomer and is in a rapidly exchanging equilibrium in intact cells at 37 degrees C with its 3.5 S hormone-binding subunit. When GH1 cells are incubated for 1 h at 37 degrees C with various concentrations of [3H]9 alpha-fluoro-11 beta, 16 alpha, 17 alpha, 21-tetrahydroxypregna-1,4-diene-3,20-dione, 16,17-acetonide ([3H]triamcinolone acetonide), receptor is found both in the cytosol and the nucleus. Sedimentation of the cytosol in low salt gradients reveals that a 4 S receptor form is present along with 10 S receptor. As the concentration of [3H]triamcinolone acetonide is increased, the amounts of both 4 S cytosolic receptor and nuclear receptor increase and the amount of 10 S cytosolic receptor decreases. Following removal of [3H]triamcinolone acetonide from cells, the amounts of both 4 S cytosolic receptor and nuclear receptor decrease and the amount of 10 S cytosolic receptor increases. Density labeling indicates that this increase in 10 S receptor is not due to new receptor synthesis. The 4 S receptor form, but not the 10 S form, binds to purified DNA. Resedimentation studies suggest that the 4 S receptor found in low salt gradients is identical with or derived from the 3.5 S form found in salt-containing gradients. A model for hormone-mediated receptor translocation to the nucleus is proposed in which binding of hormone shifts the equilibrium between the oligomeric 10 S receptor and its 4 S subunit toward the 4 S form. The 4 S form is in equilibrium with 4 S receptor bound to chromatin. The model provides a molecular explanation for many experimental findings concerning glucocorticoid and other steroid receptors.
Publication
Journal: Antiviral Research
August/11/2003
Abstract
The effects of Ocimum gratissimum (GHX-2), Ficus polita (GHX-6), Clausena anisata (GHX-7), Alchornea cordifolia (GHX-26), Elaeophorbia drupifera (GHX-27), and AZT on in vitro HIV-1 and HIV-2 replication and cytopathicity were compared. All plant extracts inhibited HIV-1 strain HTLVIII(B) cytopathicity, the leaves of GHX-2 and the seeds of GHX-26 having high antiviral indices (110 and 90, respectively). Against HIV-2 strain GH1, the EC(50) values ranged from <0.005 to 0.075 mg/ml when treatment was started at 40min after virus adsorption, except for GHX-7 which showed only moderate activity and GHX-26 which had no activity. When treatment was delayed for 2h, the plant extracts, unlike AZT, were still very effective against HIV-2. Likewise, only the plant extracts were able to attain EC(90) values when high multiplicity of infection (MOI) with HIV-1 strain GH3 was used when treatment was delayed for 2h. In Molt-4 cocultures with Molt-4/HIV, early cytopathic effect (CPE) of cell fusion was unaffected by AZT but was completely inhibited by all plants at noncytotoxic concentrations. In addition, GHX-27 was selectively toxic to Molt-4/HIV cells. The plant extracts also inhibited HIV-1 reverse transcriptase (RT) activity at EC(50) values of <0.01-0.03 mg/ml. HIV-1 proviral DNA copying as determined in a polymerase chain reaction, was completely inhibited by GHX-2 and GHX-6 at 0.011 and 0.015 mg/ml, respectively. GHX-26 and GHX-27 showed only very moderate activity.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
May/27/2010
Abstract
BACKGROUND
The human growth hormone/chorionic somatomammotropin (hGH/CSH) locus at 17q22-24, consisting of one pituitary-expressed postnatal (GH1) and four placenta-expressed genes (GH2, CSH1, CSH2, and CSHL1), is implicated in regulation of postnatal and intrauterine growth. A positive correlation has been reported between the offspring's birth weight and serum placental GH (coded by GH2) and placental lactogen (coded by CSH1, CSH2) levels in pregnant women.
OBJECTIVE
The objective of the study was the investigation of the hypothesis that the mRNA expression profile of placental hGH/CSH genes contributes to the determination of birth weight.
METHODS
We developed a sensitive, fluorescent-labeled semiquantitative RT-PCR assay coupled with gene-specific restriction analysis, capable of distinguishing alternative splice-products of individual placental hGH/CSH genes and quantification of their relative expression levels. The detailed profile of alternative transcripts of GH2, CSH1, CSH2, and CSHL1 genes in placenta from uncomplicated term pregnancies of the REPROMETA sample collection was addressed in association with the birth weight of newborns, grouped as appropriate for gestational age (AGA; n = 23), small for gestational age (SGA; n = 15), and large for gestational age (LGA; n = 34).
RESULTS
The majority of pregnancies with SGA newborn showed down-regulation of the entire hGH/CSH cluster in placenta, whereas in the case of LGA, the expression of CSH1-1, CSH2-1, and CSHL1-4 mRNA transcripts in placenta was significantly increased compared with AGA newborns (P < 0.0001, P = 0.009, P = 0.002, respectively).
CONCLUSIONS
The expression profile of placental hGH/CSH genes in placenta is altered in pregnancies accompanied by SGA and LGA compared with AGA newborns, and thus, it may directly affect the circulating fetal and maternal placental GH and placental lactogen levels.
Publication
Journal: Plant Physiology
November/22/2009
Abstract
Glycoside hydrolase family 1 (GH1) beta-glucosidases play roles in many processes in plants, such as chemical defense, alkaloid metabolism, hydrolysis of cell wall-derived oligosaccharides, phytohormone regulation, and lignification. However, the functions of most of the 34 GH1 gene products in rice (Oryza sativa) are unknown. Os3BGlu6, a rice beta-glucosidase representing a previously uncharacterized phylogenetic cluster of GH1, was produced in recombinant Escherichia coli. Os3BGlu6 hydrolyzed p-nitrophenyl (pNP)-beta-d-fucoside (k(cat)/K(m) = 67 mm(-1) s(-1)), pNP-beta-d-glucoside (k(cat)/K(m) = 6.2 mm(-1) s(-1)), and pNP-beta-d-galactoside (k(cat)/K(m) = 1.6 mm(-1)s(-1)) efficiently but had little activity toward other pNP glycosides. It also had high activity toward n-octyl-beta-d-glucoside and beta-(1-->3)- and beta-(1-->2)-linked disaccharides and was able to hydrolyze apigenin beta-glucoside and several other natural glycosides. Crystal structures of Os3BGlu6 and its complexes with a covalent intermediate, 2-deoxy-2-fluoroglucoside, and a nonhydrolyzable substrate analog, n-octyl-beta-d-thioglucopyranoside, were solved at 1.83, 1.81, and 1.80 A resolution, respectively. The position of the covalently trapped 2-F-glucosyl residue in the enzyme was similar to that in a 2-F-glucosyl intermediate complex of Os3BGlu7 (rice BGlu1). The side chain of methionine-251 in the mouth of the active site appeared to block the binding of extended beta-(1-->4)-linked oligosaccharides and interact with the hydrophobic aglycone of n-octyl-beta-d-thioglucopyranoside. This correlates with the preference of Os3BGlu6 for short oligosaccharides and hydrophobic glycosides.
Publication
Journal: Endocrine Reviews
January/11/2015
Abstract
The diagnosis of GH deficiency (GHD) in childhood is a multistep process involving clinical history, examination with detailed auxology, biochemical testing, and pituitary imaging, with an increasing contribution from genetics in patients with congenital GHD. Our increasing understanding of the factors involved in the development of somatotropes and the dynamic function of the somatotrope network may explain, at least in part, the development and progression of childhood GHD in different age groups. With respect to the genetic etiology of isolated GHD (IGHD), mutations in known genes such as those encoding GH (GH1), GHRH receptor (GHRHR), or transcription factors involved in pituitary development, are identified in a relatively small percentage of patients suggesting the involvement of other, yet unidentified, factors. Genome-wide association studies point toward an increasing number of genes involved in the control of growth, but their role in the etiology of IGHD remains unknown. Despite the many years of research in the area of GHD, there are still controversies on the etiology, diagnosis, and management of IGHD in children. Recent data suggest that childhood IGHD may have a wider impact on the health and neurodevelopment of children, but it is yet unknown to what extent treatment with recombinant human GH can reverse this effect. Finally, the safety of recombinant human GH is currently the subject of much debate and research, and it is clear that long-term controlled studies are needed to clarify the consequences of childhood IGHD and the long-term safety of its treatment.
Publication
Journal: Vaccine
March/29/2015
Abstract
METHODS
A novel, fully bacterially produced recombinant virus-like particle (VLP) based influenza vaccine (gH1-Qbeta) against A/California/07/2009(H1N1) was tested in a double-blind, randomized phase I clinical trial at two clinical sites in Singapore. The trial evaluated the immunogenicity and safety of gH1-Qbeta in the presence or absence of alhydrogel adjuvant. Healthy adult volunteers with no or low pre-existing immunity against A/California/07/2009 (H1N1) were randomized to receive two intramuscular injections 21 days apart, with 100μg vaccine, containing 42μg hemagglutinin antigen. Antibody responses were measured before and 21 days after each immunization by hemagglutination inhibition (HAI) assays. The primary endpoint was seroconversion on Day 42, defined as percentage of subjects which reach a HAI titer ≥40 or achieve an at least 4-fold rise in HAI titer (with pre-existing immunity). The co-secondary endpoints were safety and seroconversion on Day 21.
RESULTS
A total of 84 Asian volunteers were enrolled in this study and randomized to receive the adjuvanted (n=43) or the non-adjuvanted (n=41) vaccine. Of those, 43 and 37 respectively (95%) completed the study. There were no deaths or serious adverse events reported during this trial. A total of 535 adverse events occurred during treatment with 49.5% local solicited symptoms, of mostly (76.4%) mild severity. The most common treatment-related systemic symptom was fatigue. The non-adjuvanted vaccine met all primary and secondary endpoints and showed seroconversion in 62.2% and 70.3% of participants respectively on Day 21 and Day 42. While the adjuvanted vaccine showed an increased seroconversion from 25.5% (Day 21) to 51.2% (Day 42), it did not meet the immunogenicity endpoint.
CONCLUSIONS
In summary, non-adjuvanted gH1-Qbeta showed similar antibody mediated immunogenicity and a comparable safety profile in healthy humans to commercially available vaccines. These results warrant the consideration of this VLP vaccine platform for the vaccination against influenza infection (HSA CTC1300092).
Publication
Journal: PLoS ONE
March/5/2013
Abstract
The human gastrointestinal tract can be positively modulated by dietary supplementation of probiotic bacteria in combination with prebiotic carbohydrates. Here differential transcriptomics and functional genomics were used to identify genes in Lactobacillus acidophilus NCFM involved in the uptake and catabolism of 11 potential prebiotic compounds consisting of α- and β-linked galactosides and glucosides. These oligosaccharides induced genes encoding phosphoenolpyruvate-dependent sugar phosphotransferase systems (PTS), galactoside pentose hexuronide (GPH) permease, and ATP-binding cassette (ABC) transporters. PTS systems were upregulated primarily by di- and tri-saccharides such as cellobiose, isomaltose, isomaltulose, panose and gentiobiose, while ABC transporters were upregulated by raffinose, Polydextrose, and stachyose. A single GPH transporter was induced by lactitol and galactooligosaccharides (GOS). The various transporters were associated with a number of glycoside hydrolases from families 1, 2, 4, 13, 32, 36, 42, and 65, involved in the catabolism of various α- and β-linked glucosides and galactosides. Further subfamily specialization was also observed for different PTS-associated GH1 6-phospho-β-glucosidases implicated in the catabolism of gentiobiose and cellobiose. These findings highlight the broad oligosaccharide metabolic repertoire of L. acidophilus NCFM and establish a platform for selection and screening of both probiotic bacteria and prebiotic compounds that may positively influence the gastrointestinal microbiota.
Publication
Journal: Clinical Cancer Research
September/4/2018
Abstract
Purpose: Pituitary adenomas are one of the most common benign neoplasms of the central nervous system. Although emerging evidence suggests roles for both genetic and epigenetic factors in tumorigenesis, the degree to which these factors contribute to disease remains poorly understood.Experimental Design: A multiplatform analysis was performed to identify the genomic and epigenomic underpinnings of disease among the three major subtypes of surgically resected pituitary adenomas in 48 patients: growth hormone (GH)-secreting (n = 17), adrenocorticotropic hormone (ACTH)-secreting (n = 13, including 3 silent-ACTH adenomas), and endocrine-inactive (n = 18). Whole-exome sequencing was used to profile the somatic mutational landscape, whole-transcriptome sequencing was used to identify disease-specific patterns of gene expression, and array-based DNA methylation profiling was used to examine genome-wide patterns of DNA methylation.Results: Recurrent single-nucleotide and small indel somatic mutations were infrequent among the three adenoma subtypes. However, somatic copy-number alterations (SCNA) were identified in all three pituitary adenoma subtypes. Methylation analysis revealed adenoma subtype-specific DNA methylation profiles, with GH-secreting adenomas being dominated by hypomethylated sites. Likewise, gene-expression patterns revealed adenoma subtype-specific profiles. Integrating DNA methylation and gene-expression data revealed that hypomethylation of promoter regions are related with increased expression of GH1 and SSTR5 genes in GH-secreting adenomas and POMC gene in ACTH-secreting adenomas. Finally, multispectral IHC staining of immune-related proteins showed abundant expression of PD-L1 among all three adenoma subtypes.Conclusions: Taken together, these data stress the contribution of epigenomic alterations to disease-specific etiology among adenoma subtypes and highlight potential targets for future immunotherapy-based treatments. This article reveals novel insights into the epigenomics underlying pituitary adenomas and highlights how differences in epigenomic states are related to important transcriptome alterations that define adenoma subtypes. Clin Cancer Res; 24(17); 4126-36. ©2018 AACR.
Publication
Journal: Human Genetics
August/13/2003
Abstract
Isolated growth hormone deficiency type II (IGHD II) is characterized by short stature due to dominant-negative mutations of the human growth hormone gene (GH1). Most of the known mutations responsible for IGHD II cause aberrant splicing of GH1 transcripts. We have recently shown that mutations that cause exon 3 skipping and produce a dominant-negative 17.5-kDa isoform in humans also cause a dose-dependent disruption of GH secretory vesicles when expressed in GC cells and transgenic mice. We show here that overexpression of the dominant-negative 17.5-kDa isoform also destroys the majority of somatotrophs, leading to anterior pituitary hypoplasia in transgenic mice. It is, therefore, important to understand the regulation of GH1 splicing and why its perturbation causes IGHD II. We demonstrate that dual splicing enhancers are required to ensure exon 3 definition to produce full-length 22-kDa hormone. We also show that splicing enhancer mutations that weaken exon 3 recognition produce variable amounts of the 17.5-kDa isoform, a result which could potentially explain the clinical variability observed in IGHD II. Non-canonical splicing mutations that disrupt splicing enhancers, such as those illustrated here, demonstrate the importance of enhancer elements in regulating alternative splicing to prevent human disease.
Publication
Journal: ACS Chemical Biology
October/1/2015
Abstract
Harnessing the biotechnological potential of the large number of proteins available in sequence databases requires scalable methods for functional characterization. Here we propose a workflow to address this challenge by combining phylogenomic guided DNA synthesis with high-throughput mass spectrometry and apply it to the systematic characterization of GH1 β-glucosidases, a family of enzymes necessary for biomass hydrolysis, an important step in the conversion of lignocellulosic feedstocks to fuels and chemicals. We synthesized and expressed 175 GH1s, selected from over 2000 candidate sequences to cover maximum sequence diversity. These enzymes were functionally characterized over a range of temperatures and pHs using nanostructure-initiator mass spectrometry (NIMS), generating over 10,000 data points. When combined with HPLC-based sugar profiling, we observed GH1 enzymes active over a broad temperature range and toward many different β-linked disaccharides. For some GH1s we also observed activity toward laminarin, a more complex oligosaccharide present as a major component of macroalgae. An area of particular interest was the identification of GH1 enzymes compatible with the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), a next-generation biomass pretreatment technology. We thus searched for GH1 enzymes active at 70 °C and 20% (v/v) [C2mim][OAc] over the course of a 24-h saccharification reaction. Using our unbiased approach, we identified multiple enzymes of different phylogentic origin with such activities. Our approach of characterizing sequence diversity through targeted gene synthesis coupled to high-throughput screening technologies is a broadly applicable paradigm for a wide range of biological problems.
Publication
Journal: Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society
January/19/2011
Abstract
OBJECTIVE
We examined the risk of colorectal polyps in relation to body size factors and candidate polymorphisms in selected genes of insulin-like growth factor (IGF1) (rs5742612), IGF1 receptor (IGF1R) (rs2229765), IGF binding protein 3 (IGFBP3) (rs2854746) and growth hormone (GH1) (rs2665802).
METHODS
Cases with colorectal adenomas (n=519), hyperplastic polyps (n=691), or both lesions (n=227), and controls (n=772), aged 20-74 years, were recruited from patients who underwent colonoscopy between December 2004 and September 2007 at a large integrated-health plan in Washington state. Subjects participated in a 45-minute telephone interview to ascertain body size and physical activity, and provided a buccal DNA sample for genetic analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable polytomous regression.
RESULTS
Compared to those of normal weight, higher body mass index (BMI) was associated with elevated risk of colorectal adenomas (OR=1.65, 95% CI 1.22-2.25 BMI>or=30 kg/m(2), p-trend=0.002) and both lesions (OR=2.15, 95% CI 1.43-3.22 BMI>or=30 kg/m(2), p-trend=0.003), but there was no relationship with hyperplastic polyps. Obesity at age 18 and a weight gain of>>or=21 kg since age 18 were also significantly associated with an increased risk of colorectal adenomas and both lesions, but not hyperplastic polyps. There was a reduced risk of colorectal adenomas (OR=0.63, 95% CI 0.42-0.94) and hyperplastic polyps (OR=0.7, 95% CI 0.5-0.9) associated with the homozygous variant genotype for GH1. Few meaningful results were evident for the other polymorphisms.
CONCLUSIONS
There is an increased risk of colorectal adenomas and presence of both adenomas and hyperplastic polyps in relation to increasing body size. Some genetic variation in GH1 might contribute to a reduced risk of colorectal adenomas and hyperplastic polyps.
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