Search results for "oligo"
showing 10 items of 1298 documents
Inhibition of ubiquitin-dependent proteolysis by a synthetic glycine-alanine repeat peptide that mimics an inhibitory viral sequence.
2002
AbstractThe glycine–alanine repeat (GAr) of the Epstein–Barr virus nuclear antigen-1 is a cis-acting transferable element that inhibits ubiquitin/proteasome-dependent proteolysis in vitro and in vivo. We have here examined the effect of a synthetic 20-mer GAr oligopeptide on the degradation of iodinated or biotin labeled lysozyme in a rabbit reticulocyte lysates in vitro assay. Micromolar concentrations of the GA-20 peptide inhibited the hydrolysis of lysozyme without significant effect on ubiquitination. Addition of the peptide did not inhibit the hydrolysis of fluorogenic substrate by purified proteasomes and did not affect the ubiquitination of lysozyme. An excess of the peptide failed t…
Activation of oligodendroglial Fyn kinase enhances translation of mRNAs transported in hnRNP A2-dependent RNA granules.
2008
Central nervous system myelination requires the synthesis of large amounts of myelin basic protein (MBP) at the axon–glia contact site. MBP messenger RNA (mRNA) is transported in RNA granules to oligodendroglial processes in a translationally silenced state. This process is regulated by the trans-acting factor heterogeneous nuclear ribonucleoprotein (hnRNP) A2 binding to the cis-acting A2 response element (A2RE). Release of this repression of MBP mRNA translation is thus essential for myelination. Mice deficient in the Src family tyrosine kinase Fyn are hypomyelinated and contain reduced levels of MBP. Here, we identify hnRNP A2 as a target of activated Fyn in oligodendrocytes. We show that…
Heterogeneous nuclear ribonucleoprotein (hnRNP) F is a novel component of oligodendroglial RNA transport granules contributing to regulation of myeli…
2011
Myelin basic protein (MBP) is a major component of central nervous system (CNS) myelin. The absence of MBP results in the loss of almost all compact myelin in the CNS. MBP mRNA is sorted into RNA granules that are transported to the periphery of oligodendrocytes in a translationally inactive state. A central mediator of this transport process is the trans-acting factor heterogeneous nuclear ribonucleoprotein (hnRNP) A2 that binds to the cis-acting A2-response element in the 3′UTR of MBP mRNA. Recently, we found that activation of the Src family nonreceptor tyrosine kinase Fyn in oligodendrocytes leads to phosphorylation of hnRNP A2 and to increased translation of MBP mRNA. Here, we identify…
The diagnosis of polycystic ovary syndrome in adolescents
2010
In women, the definition of polycystic ovary syndrome (PCOS) has become broad and includes several possible phenotypes. Because several features of PCOS may be in evolution in adolescents, we suggest that only firm criteria should be used to make a diagnosis of PCOS during adolescence. Hyperandrogenism, oligomenorrhea, and ovarian morphology change during adolescence and are discussed individually. Adolescents with incomplete criteria for a firm diagnosis of PCOS should be followed up carefully and may be diagnosed at a later time.
Cytotoxicity of the bisphenolic honokiol from Magnolia officinalis against multiple drug-resistant tumor cells as determined by pharmacogenomics and …
2014
A main problem in oncology is the development of drug-resistance. Some plant-derived lignans are established in cancer therapy, e.g. the semisynthetic epipodophyllotoxins etoposide and teniposide. Their activity is, unfortunately, hampered by the ATP-binding cassette (ABC) efflux transporter, P-glycoprotein. Here, we investigated the bisphenolic honokiol derived from Magnolia officinalis. P-glycoprotein-overexpressing CEM/ADR5000 cells were not cross-resistant to honokiol, but MDA-MB-231 BRCP cells transfected with another ABC-transporter, BCRP, revealed 3-fold resistance. Further drug resistance mechanisms analyzed study was the tumor suppressor TP53 and the epidermal growth factor recepto…
Amino acid substitutions enhancing thermostability of Bacillus polymyxa beta-glucosidase A
1996
Mutations enhancing the thermostability of β-glucosidase A of Bacillus polymyxa, a family 1 glycosyl hydrolase, have been obtained after hydroxylamine mutagenesis of a plasmid containing the bglA gene, transformation of Escherichia coli with the mutagenized plasmid, and identification of transformant colonies that showed β-glucosidase activity after a thermal treatment that inactivated the wild-type enzyme. Two additive mutations have been characterized that cause replacement of glutamate at position 96 by lysine and of methionine at position 416 by isoleucine respectively. The thermoresistant mutant enzymes showed increased resistance to other denaturing agents, such as pH and urea, while …
The Saccharomyces cerevisiae zinc finger proteins Msn2p and Msn4p are required for transcriptional induction through the stress response element (STR…
1996
The MSN2 and MSN4 genes encode homologous and functionally redundant Cys2His2 zinc finger proteins. A disruption of both MSN2 and MSN4 genes results in a higher sensitivity to different stresses, including carbon source starvation, heat shock and severe osmotic and oxidative stresses. We show that MSN2 and MSN4 are required for activation of several yeast genes such as CTT1, DDR2 and HSP12, whose induction is mediated through stress-response elements (STREs). Msn2p and Msn4p are important factors for the stress-induced activation of STRE dependent promoters and bind specifically to STRE-containing oligonucleotides. Our results suggest that MSN2 and MSN4 encode a DNA-binding component of the…
PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.
2017
In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…
Darstellung einer homologen Reihe von oligoallylalkoholen mit 1-cyano-1-methylethyl-endgruppen. Beispiel einer mehrfachen matrizenreaktion und einer …
1984
Reduction and hydrolysis of the ladder oligomers 1, 2, 3, 4, and 5 prepared from the acrylates of oligo (hydroxyphenylene-methylene)s was found to lead to a homologous series of oligo (allylalcohol)s (6a, 7a, 8a, 9a and10a) with good yields. These alcohols were characterized by analytical and spectroscopic methods. The reaction sequences, starting with the esterification of the oligo[(hydroxyphenylene) methylene]s 11a – 11e with acryloyl chloride followed by the formation of the ladder oligomers and ending with their reduction and hydrolysis into the oligo(allyl alcohol)s and the starting compounds 11a – 11e, represent a simple matrix reaction. A mixture of multiple acrylates was also subje…
Rapid Access to Polyfunctional Lipids with Complex Architecture via Oxyanionic Ring-Opening Polymerization
2011
Polymer-coated liposomes, particularly poly(ethylene glycol) (PEG)-substituted liposomes, have emerged as long-circulating carrier systems for drug delivery and diagnostic purposes. A rapid synthesis of three different types of multifunctional lipids with structurally diverse hydrophilic, polyether-based architectures via one- or two-pot approaches is described. Architectural variation is achieved by the combination of different oxyanionic polymerization strategies and various glycidyl ether building units. Branched polyglycerol lipids have been prepared via cholesterol- or 1,2-bis-n-alkyl glyceryl ether-initiated, oxyanionic ring-opening polymerization (ROP) of protected glycidyl ethers an…