Search results for "reverse transcriptase"
showing 10 items of 715 documents
Specific expression of antimicrobial peptide and HSP70 genes in response to heat-shock and several bacterial challenges in mussels
2007
Abstract Defensin, mytilin and myticin are antimicrobial peptides (AMP) involved in mussel innate immunity. Their in vitro antibacterial activity is different according to the targeted bacterial species. To determine if this specificity is correlated to different regulations of gene expressions, adult mussels were challenged in vivo with either Vibrio splendidus LGP32, Vibrio anguillarum , Micrococcus lysodeikticus or by heat shock. RNAs were isolated from circulating hemocytes and AMP mRNAs were quantified by Q-PCR using 28S rRNA as housekeeping gene. In addition, HSP70 gene expression was also quantified as representing non-specific response to stress. In naive mussels, the three AMP mRNA…
Cordycepin analogues of 2',5'-oligoadenylate inhibit human immunodeficiency virus infection via inhibition of reverse transcriptase.
1991
Analogues of 2',5'-oligoadenylates (2-5A), the cordycepin (3'-deoxyadenosine) core trimer (Co3) and its 5'-monophosphate derivative (pCo3), were shown to display pronounced anti-human immunodeficiency virus type 1 (HIV-1) activity in vitro. Treatment of HIV-1 infected H9 cells with 1 microM Co3 or pCo3 resulted in an almost 100% inhibition of virus production. The compounds were encapsulated in liposomes targeted by antibodies specific for the T-cell receptor molecule CD3. Substitution of one or two cordycepin units in Co3 or pCo3 decreased the antiviral activity of the compounds. pCo3 did not stimulate 2-5A-dependent ribonuclease L activity and displayed no effect on the amount of cellular…
Vitamin A deficiency alters the structure and collagen IV composition of rat renal basement membranes.
2005
Retinoids can modulate the expression of extracellular matrix (ECM) proteins with variable results depending on other contributing factors. Because changes in these proteins may alter the composition and impair the function of specialized ECM structures such as basement membranes (BMs), we studied the effects of vitamin A deficiency on renal BMs during the growing period. Newborn male rats were fed a vitamin A-deficient (VAD) diet for 50 d. The ultrastructure of renal BMs was analyzed by electron microscopy. Total collagen IV, the different alpha(IV) chains, matrix degrading metalloproteinases (MMP), and tissue inhibitors of metalloproteinases (TIMP) were quantified by immunocytochemistry a…
Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system
2007
Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I…
Theoretical studies of HIV-1 reverse transcriptase inhibition
2012
Computational methods for accurately calculating the binding affinity of a ligand for a protein play a pivotal role in rational drug design. We herein present a theoretical study of the binding of five different ligands to one of the proteins responsible for the human immunodeficiency virus type 1 (HIV-1) cycle replication; the HIV-1 reverse transcriptase (RT). Two types of approaches are used based on molecular dynamics (MD) simulations within hybrid QM/MM potentials: the alchemical free energy perturbation method, FEP, and the pathway method, in which the ligand is physically pulled away from the binding site, thus rendering a potential of mean force (PMF) for the binding process. Our com…
MiR-221 promotes stemness of breast cancer cells by targeting DNMT3b
2016
// Giuseppina Roscigno 1, 2 , Cristina Quintavalle 1, 2 , Elvira Donnarumma 3 , Ilaria Puoti 1 , Angel Diaz-Lagares 4 , Margherita Iaboni 1 , Danilo Fiore 1 , Valentina Russo 1 , Matilde Todaro 5 , Giulia Romano 6 , Renato Thomas 7 , Giuseppina Cortino 7 , Miriam Gaggianesi 5 , Manel Esteller 4 , Carlo M. Croce 6 , Gerolama Condorelli 1, 2 1 Department of Molecular Medicine and Medical Biotechnology, “Federico II” University of Naples, Naples, Italy 2 IEOS-CNR, Naples, Italy 3 IRCCS-SDN, Naples, Italy 4 Epigenetic and Cancer Biology Program (PEBC) IDIBELL, Hospital Duran I Reynals, Barcelona, Spain 5 Department of Surgical and Oncological Sciences, Cellular and Molecular Pathophysiology Lab…
Use of Specific Chemical Reagents for Detection of Modified Nucleotides in RNA
2011
International audience; Naturally occurring cellular RNAs contain an impressive number of chemically distinct modified residues which appear posttranscriptionally, as a result of specific action of the corresponding RNA modification enzymes. Over 100 different chemical modifications have been identified and characterized up to now. Identification of the chemical nature and exact position of these modifications is typically based on 2D-TLC analysis of nucleotide digests, on HPLC coupled with mass spectrometry, or on the use of primer extension by reverse transcriptase. However, many modified nucleotides are silent in reverse transcription, since the presence of additional chemical groups fre…
Bleomycin, a selective inhibitor of DNA-dependent DNA polymerase from oncogenic RNA viruses.
1972
Abstract Bleomycin, an antibiotic, inhibits the DNA-dependent DNA polymerase from Rauscher murine leukemia virus. Higher concentrations of BLM ∗ are required to inhibit it's RNA-dependent DNA polymerase. These inhibition effects of the non-competitive type are not altered by preincubation of the DNA with BLM. Under comparable conditions neither the DNA-dependent DNA polymerase activity from E. coli and mouse liver nor the DNA-dependent RNA polymerase activity from mouse lymphoma cells are affected by BLM.
Evidence of oxidative stress in very long chain fatty acid--treated oligodendrocytes and potentialization of ROS production using RNA interference-di…
2011
X-linked adrenoleukodystrophy (X-ALD) and pseudo neonatal adrenoleukodystrophy (P-NALD) are neurodegenerative demyelinating diseases resulting from the functional loss of the peroxisomal ATP-binding cassette transporter D (ABCD1) and from single peroxisomal enzyme deficiency (Acyl-CoA oxidase1: ACOX1), respectively. As these proteins are involved in the catabolism of very long chain fatty acids (VLCFA: C24:0, C26:0), X-ALD and P-NALD patients are characterized by the accumulation of VLCFA in plasma and tissues. Since peroxisomes are involved in the metabolism of reactive oxygen species (ROS) and nitrogen species (RNS), we examined the impact of VLCFA on the oxidative status of 158N murine o…
Possible Editing of Alu Transcripts in Blood Cells of Sporadic Creutzfeldt–Jakob Disease (sCJD)
2011
Editing of RNA molecules gained major interest when coding mRNA was analyzed. A small, noncoding, Alu DNA element transcript that may act as regulatory RNA in cells was examined in this study. Alu DNA element transcription was determined in buffy coat from healthy humans and human sporadic Creutzfeldt-Jakob disease (sCJD) cases. In addition, non-sCJD controls, mostly dementia cases and Alzheimer's disease (AD) cases, were included. The Alu cDNA sequences were aligned to genomic Alu DNA elements by database search. A comparison of best aligned Alu DNA sequences with our RNA/cDNA clones revealed editing by deamination by ADAR (adenosine deaminase acting on RNA) and APOBEC (apolipoprotein B ed…