Search results for "Ribonuclease"
showing 10 items of 189 documents
Association of AUUUA-binding Protein with A + U-rich mRNA during nucleo-cytoplasmic transport
1992
Resealed nuclear envelope (NE) vesicles from rat liver containing entrapped exogenous RNA were used to study the effect of adenosine+uridine binding factor (AUBF), present in cytosolic cell extracts, on ATP-dependent transport of A+U-rich RNA (AU+RNA) and A+U-free RNA (AU-RNA) across the NE. This factor specifically binds to A+U-rich sequences present in the 3' untranslated regions of lymphokine and cytokine mRNAs, containing overlapping AUUUA boxes (granulocyte-macrophage colony stimulating factor, interleukin-3). Addition of AUBF to the extravesicular compartment markedly increased the efflux of the in vitro transcribed, capped and polyadenylated AU+ RNAs. Export of entrapped AU- control …
Hypoxia-stimulated expression of angiogenic growth factors in cervical cancer cells and cervical cancer-derived fibroblasts
2001
It is generally accepted that local growth of solid tumors and their ability to establish distant metastases are dependent on the formation of new blood vessels arising from preexisting ones (angiogenesis). The angiogenic response of the host is mediated by angiogenic molecules that are released from cancer and normal stroma cells, especially fibroblasts. The goal of the present study was to quantitatively compare the expression of the two most important angiogenic growth factors (VEGF, angiogenin) of cervical cancer cells (HeLa and Me-180) with that of cervical cancer-derived fibroblasts (from one tumor/patient) under defined normoxic and hypoxic conditions in vitro. The growth kinetics of…
DNASE1L3 deficiency, new phenotypes, and evidence for a transient type I IFN signaling.
2022
Background: Deoxyribonuclease 1 like 3 (DNASE1L3) is a secreted enzyme that has been shown to digest the extracellular chromatin derived from apoptotic bodies, and DNASE1L3 pathogenic variants have been associated with a lupus phenotype. It is unclear whether interferon signaling is sustained in DNASE1L3 deficiency in humans. Objectives: To explore interferon signaling in DNASE1L3 deficient patients. To depict the characteristic features of DNASE1L3 deficiencies in human. Methods: We identified, characterized, and analyzed five new patients carrying biallelic DNASE1L3 variations. Whole or targeted exome and/or Sanger sequencing was performed to detect pathogenic variations in five juvenile …
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…
Depletion ofL-arginine induces autophagy as a cytoprotective response to endoplasmic reticulum stress in human T lymphocytes
2012
PMCID: PMC3494587
Functional characterization of the enhancer blocking element of the sea urchin early histone gene cluster reveals insulator properties and three esse…
2000
Insulator elements can be functionally identified by their ability to shield promoters from regulators in a position-dependent manner or their ability to protect adjacent transgenes from position effects. We have previously reported the identification of a 265 bp sns DNA fragment at the 3' end of the sea urchin H2A early histone gene that blocked expression of a reporter gene in transgenic embryos when placed between the enhancer and the promoter. Here we show that sns interferes with enhancer-promoter interaction in a directional manner. When sns is placed between the H2A modulator and the inducible tet operator, the modulator is barred from interaction with the basal promoter. However, th…
[33] Use of repair endonucleases to assess DNA damage by peroxynitrite
1999
Publisher Summary This chapter discusses the use of repair endonucleases to assess DNA damage by peroxynitrite. Repair endonucleases allow a convenient quantification of various types of oxidative modifications induced by peroxynitrite, both in cultured cells and in cell-free DNA. The high sensitivity of the assays allows highly ectotoxic exposure conditions to be avoided—as well as the generation of secondary DNA modifications—that often become a problem at high levels of damage because primary DNA oxidation products can be orders of magnitude more reactive than the original bases, as demonstrated for the reaction of 8-hydroxyguanine with singlet oxygen. The ratio of the various types of m…
Chromatin structure of the 5′ flanking region of the yeastLEU2 gene
1989
The chromatin structure of theLEU2 gene and its flanks has been studied by means of nuclease digestion, both with micrococcal nuclease and DNase I. The gene is organized in an array of positioned nucleosomes. Within the promoter region, the nucleosome positioning places the regulatory sequences, putative TATA box and upstream activator sequence outside the nucleosomal cores. The tRNA3 Leu gene possesses a characteristic structure and is protected against nucleases. Most of the 5′ flank is sensitive to DNase I digestion, although no clear hypersensitive sites were found. The chromatin structure is independent of either the transcriptional state of the gene or the chromosomal or episomal loca…
Modulation of Nuclear Matrix-associated 2′,5′-Oligoadenylate Metabolism and Ribonuclease L Activity in H9 Cells by Human Immunodeficiency Virus
1989
Human T cells (H9), infected with the HTLV-IIIB strain of the human immunodeficiency virus (HIV-1), have been used to study the alteration of 2',5'-oligoadenylate [2'-5')A) metabolism in relation to virus production. The synthesis of (2'-5')A was determined to proceed in close association with the nuclear matrix. After HIV infection the (2'-5')A synthetase activity increased from 1.1 to 1.5 pmol of (2'-5')A synthesized/100 micrograms of nuclear matrix protein (during a 3-h in vitro incubation period) to 8.2 pmol at day 3 after infection. Then the activity dropped to the initial values. In non-infected H9 cells the (2'-5')A synthetase activity remained unchanged. Simultaneously with the decr…
Lactobacillus tucceti sp. nov., a new lactic acid bacterium isolated from sausage
2006
Abstract Following the application of several molecular techniques strain R 19c, isolated from sausage by Reuter in 1970 and deposited at the DSMZ as Lactobacillus sp., has been identified as pertaining to a new species. It showed singular ISR- Dde I and ISR- Hae III profiles that allowed its differentiation from 68 lactic acid bacteria reference strains analyzed. Phylogenetic analysis based on 16S rRNA gene sequences places this strain in the genus Lactobacillus within the Lactobacillus alimentarius group. Species L. versmoldensis is the closest phylogenetic neighbor with 96.3% sequence similarity. DNA–DNA hybridization experiments confirmed the independent status at species level of this …