Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.27.1 (RNase)
16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies showed that an antigen found in the circulation of animals heavily infected with Schistosoma mansoni was extracted in a trichloroacetic acid soluble-chloroform insoluble fraction (TCA-S-C) of adult worms. Antigenic activity was destroyed by periodate treatment but remained unaltered after treatment with proteolytic enzymes, DNase, RNase, and lyophilization. In the present study, chromatography of TCA-S-C on a DEAE cellulose column revealed six substances, one of which was antigenic. After electrophoresis in agarose antigenic activity corresponded to a slower moving, toluidine blue-staining material. A faster moving, toluidine blue-staining substance seems to be responsible for the large 260 nm, absorbing peak. Analysis of a fraction containing only antigen revealed a large amount of carbohydrate, primarily N-acetylglucosamine and D-glucuronic acid but also galactase, glucose, N-acetylglucosamine, and trace amounts of other sugars. Amino acids accounted for about 11% of the weight of the antigen. The antigen appears to be a proteoglycan.
...
PMID:Further purification and characterization of a circulating antigen in schistosomiasis. 41 Aug 79

An efficient method for the isolation of RNA from cartilage is described. The difficulties in obtaining RNA from cartilage, a tissue of low cell density and high proteoglycan content, were overcome by making several modifications to the guanidine thiocyanate/cesium chloride method of RNA extraction. Cartilage tissue is frozen, crushed, and homogenized in a 4 M guanidine thiocyanate lysis buffer. The RNA is then pelleted by ultracentrifugation through a cesium trifluoroacetate density gradient. The use of cesium trifluoroacetate, rather than cesium chloride, for density gradient centrifugation improves both the yield and purity of total RNA isolated from cartilage. The ultracentrifugation has been adapted to the Beckman TL100 tabletop centrifuge and is complete in 3 h. This fast, simple method produces high quality RNA, suitable for use in RNase protection assays, polymerase chain reaction analysis, and Northern analysis. This purification procedure may be applicable to other sources, from which RNA isolation is complicated by the presence of abundant cell wall or matrix components.
...
PMID:RNA isolation from cartilage using density gradient centrifugation in cesium trifluoroacetate: an RNA preparation technique effective in the presence of high proteoglycan content. 138 88

A cDNA clone coding for a membrane proteoglycan core protein was isolated from a neonatal rat Schwann cell cDNA library by screening with an oligonucleotide based on a conserved sequence in cDNAs coding for previously described proteoglycan core proteins. Primer extension and polymerase chain reaction amplification were used to obtain additional 5' protein coding sequences. The deduced amino acid sequence predicted a 353 amino acid polypeptide with a single membrane spanning segment and a 34 amino acid hydrophilic COOH-terminal cytoplasmic domain. The putative extracellular domain contains three potential glycosaminoglycan attachment sites, as well as a domain rich in Thr and Pro residues. Analysis of the cDNA and deduced amino acid sequences revealed a high degree of identity with the transmembrane and cytoplasmic domains of previously described proteoglycans but a unique extracellular domain sequence. On Northern blots the cDNA hybridized to a single 5.6-kb mRNA that was present in Schwann cells, neonatal rat brain, rat heart, and rat smooth muscle cells. A 16-kD protein fragment encoded by the cDNA was expressed in bacteria and used to immunize rabbits. The resulting antibodies reacted on immunoblots with the core protein of a detergent extracted heparan sulfate proteoglycan. The core protein had an apparent mass of 120 kD. When the anti-core protein antibodies were used to stain tissue sections immunoreactivity was present in peripheral nerve, newborn rat brain, heart, aorta, and other neonatal tissues. A ribonuclease protection assay was used to quantitate levels of the core protein mRNA. High levels were found in neonatal rat brain, heart, and Schwann cells. The mRNA was barely detectable in neonatal or adult liver, or adult brain.
...
PMID:Molecular cloning and characterization of N-syndecan, a novel transmembrane heparan sulfate proteoglycan. 155 52

We have isolated a factor that copurifies with chondroitin sulfate proteoglycan secreted by mouse splenocytes and some murine T-cell hybridomas. This factor will stimulate proliferation and plaque-forming cell differentiation of B lymphocytes from mouse spleens, even after T cells have been depleted (less than 2% Thy 1.2-bearing cells). Adherent macrophages enhance the activity of this factor, but their function can be replaced in macrophage- and T-cell-depleted populations by small concentrations of a protein mitogen from Salmonella typhimurium. The stimulatory fraction contains chondroitin sulfate, a major protein which has a molecular weight of 74,000 and a minor moiety at 50,000. Stimulatory activity of this material is destroyed by (i) boiling, (ii) mild alkali treatment, and (iii) protease digestion. It is unaffected by RNase and chondroitinase treatments, suggesting that the factor is a protein. Our data define a new B-cell stimulatory substance(s) and suggest that it may be associated with chondroitin sulfate proteoglycan secreted by immune cells.
...
PMID:Stimulation of mouse B cells by a factor that coisolates with T-cell proteoglycan. 309 Dec 76

Rat brain extracts contain two heat-stable, nondialyzable inhibitors of tubulinyl-tyrosine carboxypeptidase. One of the inhibitors was sensitive to ribonuclease and insensitive to trypsin and pronase, indicating that the inhibitor is RNA. This is supported by the observation that purified RNA from rat brain inhibited the enzyme activity to the same extent as similar amounts of the endogenous RNA. Similar results were obtained with calf liver RNA. The other inhibitor was purified by chromatography on a DEAE-Sephadex and identified as proteoglycan. The elimination of the protein moiety of the proteoglycan resulted in a small increase of its inhibitory activity. Glycosaminoglycan was released from the proteoglycan by beta elimination, indicating that the linkage between glycosaminoglycan and the protein moiety is through an O-glycosidic bond. The glycosaminoglycan contains uronic acid, hexosamine and sulfate in a molar ratio of 1:1.01:0.99, respectively. Treatment of the glycosaminoglycan with chondroitinase ABC completely abolished its inhibitory activity. Chondroitin sulfate A, chondroitin sulfate B, chondroitin sulfate C, and the brain glycosaminoglycan inhibited tubulinyl-tyrosine carboxypeptidase to the same extent when used in comparable amounts.
...
PMID:Inhibition of tubulinyl-tyrosine carboxypeptidase by brain soluble RNA and proteoglycan. 616 Nov 29

Perlecan is a modular heparan sulfate proteoglycan that harbors five domains with homology to the low density lipoprotein receptor, epidermal growth factor, laminin and neural cell adhesion molecule. Using a monoclonal antibody directed against the laminin-like domain of perlecan, we have recently shown that perlecan is widely expressed in all lymphoreticular systems. To investigate further this observation we have studied the expression of perlecan in two human leukemic cell lines. Using reverse transcriptase-PCR, ribonuclease protection assay, and metabolic labeling we detected significant perlecan expression in the multipotential cell line K562, originally derived from a patient with chronic myelogenous leukemia. In contrast, the promyelocytic cell line HL-60 expressed perlecan at barely detectable levels. These results were intriguing because the K562 cells do not assemble or produce a classical basement membrane. Following induction with either sodium butyrate or the phorbol diester 12-0-tetradecanoylphorbol-13-acetate (TPA), K562 and HL-60 differentiate into early progenitor cells with erythroid or megakaryocytic properties, respectively. Following treatment of K562 and HL-60 cells with either of these agents, perlecan expression was markedly increased in K562 cells. In contrast, we could detect perlecan protein synthesis in HL-60 cells only at very low levels, even after induction with TPA or sodium butyrate. Collectively, these results indicate that perlecan is actively synthesized by bone marrow derived cells and suggest that this proteoglycan may play a role in hematopoietic cell differentiation.
...
PMID:The proteoglycan perlecan is expressed in the erythroleukemia cell line K562 and is upregulated by sodium butyrate and phorbol ester. 754 67

RNA isolated by conventional guanidinium isothiocyanate methods from tissues of a mollusc (red abalone: Haliotis rufescens) is largely degraded and discolored by contaminants. These contaminants are associated with inhibition of reverse transcriptase, prevent accurate spectrophotometric determination of RNA concentration, and impart undesirable viscosity to the preparations. A cold two-step method of RNA isolation was devised which provides high yields of full-length RNA templates from these tissues and eliminates the discolored contaminant. Immediately following homogenization of tissues at ca. 5 degrees C, which proved crucial for the recovery of high-molecular weight species, the RNA is isolated from the bulk of the RNase by a single acid-phenol-chloroform extraction at 0 degrees C. The inhibitor of reverse transcriptase, suspected to be a proteoglycan (or a similar high-molecular-weight polyanion) component of the intestinal mucus, is eliminated only by a second purification step employing ultracentrifugation through a dense cushion of CsCl. This cold two-step method should prove useful for providing full-length RNA templates relatively free of polysaccharide, a common contaminant of RNA preparations, from both plant and animal tissues.
...
PMID:Isolation of full-length RNA templates for reverse transcription from tissues rich in RNase and proteoglycans. 768 67

We have isolated, sequenced, and characterized a human MN/CA9 gene. This gene is a novel member of the carbonic anhydrase (CA) family, which codes for widely distributed catalysts of the reversible conversion of carbon dioxide to carbonic acid. So far, MN/CA IX is the only tumor-associated CA isoenzyme. The entire genomic sequence of MN/CA9, including the 5'-flanking region, encompasses 10.9 kb. The coding sequence is divided into 11 exons, whose organization and relationships to predicted protein domains suggest that the gene arose by exon shuffling. Exon 1 encodes a signal peptide and a proteoglycan-related region. Exons 2-8 code for a CA domain with a highly conserved active site. The exon/intron pattern of the CA coding region is similar but not identical to other described animal kingdom alpha-CA genes. Exons 10 and 11 encode a transmembrane anchor and an intracytoplasmic tail, respectively. We have also determined the transcription initiation and termination sites by RNase protection assay and analyzed the 3. 5-kb region upstream of the MN/CA9 gene. Sequence of the proximate 5' end of the flanking region shows extensive homology to the long terminal repeats of HERV-K endogenous retroviruses. The putative MN/CA9 promoter immediately preceding the transcription start site does not possess a TATA box, but contains consensus sequences for the AP1, AP2, p53, and Inr transcription factors. This study will allow further investigations of the molecular events regulating expression of MN/CA IX as well as elucidation of its biological function.
...
PMID:Human MN/CA9 gene, a novel member of the carbonic anhydrase family: structure and exon to protein domain relationships. 866 Oct 7

The three-dimensional structure of human decorin, a secreted proteoglycan involved in the regulation of collagen fibrillogenesis and cellular growth, has been modeled based on the crystal structure of the porcine ribonuclease inhibitor. Both proteins contain leucine-rich repeats and share 18% identical residues. This model structure of decorin has an arch shape with the single glycosaminoglycan chain and the three N-linked oligosaccharides located on the same side of the molecule. Decorin was modeled as binding to a polar sequence of collagen type I found in the d band. The inner concave surface is the appropriate size and shape to accommodate only one collagen triple helix of approximately 3 nm in length. The binding of one collagen triple helix to decorin is proposed to play a major role in the formation of the staggered arrangement of collagen molecules within the microfibrils by preventing lateral fusion of collagen molecules.
...
PMID:Model structure of decorin and implications for collagen fibrillogenesis. 894 11

Brevican is a brain-specific proteoglycan belonging to the aggrecan family. Phage clones containing the complete mouse brevican open reading frame of 2649 bp and the complete 3'-untranslated region of 341 bp were isolated from a mouse brain cDNA library, and cosmid clones containing the mouse brevican gene were isolated from a genomic library using a PCR-generated DNA fragment as probe. The obtained genomic sequence of 13,700 nucleotides revealed that the murine gene has a size of approximately 13 kb and contains the sequence of the mRNA for the secreted brevican isoform on 14 exons. The exon-intron structure reflected the structural organization of the multidomain protein brevican. No consensus TATA sequence was found upstream of the first exon, and RNase protection experiments revealed multiple transcriptional start sites for the brevican gene. The first part of the sequence of intron 8 corresponded to an alternative brevican cDNA, coding for a GPI-linked isoform. Single strand conformation polymorphism analysis mapped the brevican gene (Bcan) to chromosome 3 between the microsatellite markers D3Mit22 and D3Mit11.
...
PMID:Sequence and chromosomal localization of the mouse brevican gene. 928 96


1 2 Next >>

---