Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The nuclear matrix of adrenal cells was isolated by using the methods proposed by Commerford et al and Kaufmann et al for the liver nuclear matrix isolation. Both methods permitted, to the best of our knowledge for the first time, to prepare the nuclear matrix of a steroidogenic cell and therefore to study some regulatory mechanisms governing steroidogenesis. Commerford et al's method retains nuclear envelope and so produces a higher contamination; Kaufmann et al's method presents a higher purity since the nuclear envelope was removed by Triton X-100. No RNase digestion has been employed for the isolation of the residual nuclear matrices. Both methods however, permit the isolation of fractions with a good morphology, retaining a reticular nucleolus, interchromatinic granules, and a fibrogranular scaffold extending from the nucleolus to the nuclear lamina. The major peptides detected by 1-D SDS-PAGE were 123, 56, 46 and 41 kDa; with both methods protein profiles were similar. Identification of proteins by immunodetection reveals lamins A and C, 80 and 65 kDa respectively; no labeling was found for actin (45 kDa) and vimentin (57 kDa). In short, adrenal nuclear matrix was isolated, Kaufmann et al's method being the method of choice.
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PMID:Adrenal nuclear matrix isolation. A morphologic and biochemical study. 816 67

S1 proteins A-D are hnRNP proteins which were originally isolated from nuclei of various tissues, by selective extraction of pH 4.9 from the supernatants of nuclei mildly treated with DNase I or RNase A. In the present study, a hybridoma was isolated which produced a monoclonal antibody that reacted specifically with S1 proteins C2 and D2. When the antibody was used in indirect immunofluorescence staining of cultured cells, it stained, in addition to the nuclei, the cytoskeleton-like fibrous structures in the cytoplasm. We demonstrate that the cytoskeletal filaments are vimentin intermediate filaments. This is the first report on the hnRNP protein-association with cytoskeleton, and will help to clarify cytoplasmic mRNA localization as well as cytoplasmic distribution of hnRNP proteins.
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PMID:Association of hnRNP S1 proteins C2 and D2 with vimentin intermediate filaments. 919 49

While much evidence indicates a high degree of spatial organization in the nucleus, the underlying molecular structures that support it remain poorly characterized. By extracting with high concentrations of RNase A in a modification of the sequential extraction protocol of Penman, we have identified a novel intranuclear network in the mouse lymphoma cell line, EL-4. Micrographs of embedment-free sections of extracted cells reveal anastomosing filaments of two different diameters: 3-5 nm and 8-10 nm. The 3-5-nm filaments are interconnected in many junctions and appear to blend smoothly into each other. The 8-10-nm fibers frequently split into two 3-5-nm filaments. Some 3-5-nm fibers appear to be connected at 90 degrees angles with the 8-10-nm fibers. All junctions are smooth with no apparent junction protein. Flow cytometric analysis of RNase A- (and DNase I-) extracted nuclear matrices indicates that they do not contain significant amounts of protein that react with anti-actin and anti-vimentin monoclonal antibodies. Extraction of EL-4 nuclear matrices with high salt does not reveal 8-10-nm core filaments described after similar treatment of tumor cell lines of cervical and mammary origin. The novel characteristics of the core filaments in EL-4 lymphoma cells may reflect cell-type specificity of the nuclear matrix.
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PMID:Intranuclear network of 3-5 nm and 8-10 nm fibers in EL-4 lymphoma cells. 926 90

Previously, whole-mount electron microscopy of nuclei extruded together with residual cytoplasm from the rhizoids of several algal species of the order Dasycladales has revealed the occurrence of an intra- and perinuclear network of 10-nm filaments morphologically indistinguishable from that of mammalian vimentin intermediate filaments. The present investigation demonstrates the existence of a filament system throughout the cytoplasm of the rhizoid, stalk, and apical tip of these giant cells. However, while the perinuclear 10-nm filaments interconnecting the nuclear surface with a perinuclear layer of large, electron-dense bodies filled with nucleoprotein material are of smooth appearance, those continuing within and beyond the perinuclear bodies are densely covered with differently sized, globular structures and, therefore, are of a very rough appearance. The filaments in the very apical tip of the cells are mainly of the smooth type. The transition from smooth to rough filaments seems to occur in the numerous perinuclear dense bodies surrounding the large nucleus. Digestion of the rough filaments with proteinase K removes the globules from the filament surface, revealing that throughout the nonvacuolar, intracellular space the filaments have the same basic 10-nm structure. On the other hand, gold-conjugated RNase A strongly binds to the filament-attached globules but not to the smooth, perinuclear, and the proteinase K-treated, rough filaments. In addition, an antibody raised against Xp54, a highly conserved protein which in Xenopus oocytes is an integral component of stored mRNP particles, decorates the rough but not the smooth 10-nm filaments. These results support the notion that the 10-nm filament system of Dasycladales cells plays a role in the transient storage of ribonucleoprotein particles in the cytoplasm and possibly fulfils a supportive function in the actomyosin-based transport of such material to various cytological destinations.
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PMID:Occurrence of proteinaceous 10-nm filaments throughout the cytoplasm of algae of the order Dasycladales. 959 90

The basic helix-loop-helix (bHLH) class of proteins are of major importance in controlling tissue-specific gene expression. The actions of the bHLH proteins are inhibited by a related class of proteins, inhibitors of differentiation (Id). We have studied the expression of one of these latter proteins, Id-1, in the normal and post-ischemic regenerating rat kidney by immunocytochemistry, Western blot and RNase protection assay (RPA) and correlated Id-1 regulation to the expression of vimentin and proliferating cellular nuclear antigen (PCNA). In the normal kidney strong immunostaining for Id-1 was found in the distal nephron, especially in the distal convoluted tubule in the cortex. In particular, the perinuclear region was intensely stained in the cells of the distal tubule. mRNA for Id-1I was detectable by RPA on total RNA extracted from the renal cortex of sham-operated animals. The Id-1 monomer was detected on Western blots of normal animals. Vimentin was expressed in the mesangial cells of the glomeruli and in cells in the interstitium while tubule cells were negative. The labeling intensity for PCNA was low in all cellular compartments in the normal kidney. In the regenerating kidneys at various time intervals, the expression of Id-1-like immunoreactivity was widespread in the regenerating dedifferentiated tubule cells while by the end of the study period, more highly differentiated tubule cells appeared to lose their staining. On Western blots the Id-1 monomer was undetectable and instead strong staining was seen in the high molecular range. Id-1 mRNA levels in the regenerating kidneys did not differ significantly when compared to sham. PCNA labeling was intense in the regenerating kidneys at all time periods studied, indicating the intense proliferative activity in the regenerating kidneys. Vimentin expression in the renal tubule cells was increased from day 3 and onward. The data are consistent with a hypothesis in which Id-1 regulates differentiation of renal tubule cells in the post-ischemic regenerating rat kidney.
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PMID:Expression of Id-1 mRNA and protein in the post-ischemic regenerating rat kidney. 963 41

All studies analyzing the localization of angiotensin II (Ang II) receptors in the human kidney have been performed at the protein level using 125I-Ang II as a probe. In this study, cellular localizations of Ang II type l (AT1-R) and type 2 (AT2-R) receptor mRNAs in the adult human renal cortex were examined for the first time using in situ hybridization, and their expression patterns determined by RNase protection assay were compared with those in other human tissues. In the human renal cortex obtained from tumor-free portions in renal cell carcinoma, AT1-R mRNA levels were about 8- to 10-fold higher than AT2-R mRNA levels. Human liver and aorta predominantly expressed AT1-R mRNA, while human right atrium contained both AT1-R and AT2-R mRNAs. Ligand-binding assays revealed that the total Ang II receptor number in the human renal cortex was 16.0 +/- 3.3 fmol/mg protein, similar to that in liver (17.7 +/- 5. 8) but significantly higher than in right atrium (11.6 +/- 3.2) and aorta (5.6 +/- 2.7). Relative distribution ratios of AT1-R and AT2-R numbers in the renal cortex and right atrium were 82/17 and 56/42%, respectively. In situ hybridization study indicated that strongest AT1-R mRNA signals were located in interlobular arteries and tubulointerstitial fibrous regions surrounding interlobular arteries and glomeruli, followed in decreasing order by glomeruli and cortical tubules. Expression of AT2-R mRNA was highly localized in interlobular arteries. Cells present in tubulointerstitial regions were positive for vimentin and collagen type 1, indicating that the majority of the cells present in the regions are fibroblasts. Presence of strong AT1-R mRNA signals in the tubulointerstitial fibrous regions surrounding arteries and glomeruli and the expression of AT2-R mRNA in the interlobular artery were the first evidence, suggesting a pharmacological framework for the differential effects of Ang II receptor subtype mediated renal function in the adult human kidney.
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PMID:Tissue-specific expression of human angiotensin II AT1 and AT2 receptors and cellular localization of subtype mRNAs in adult human renal cortex using in situ hybridization. 973 Jun 99

The purpose of this study is to evaluate the role of keratinocyte growth factor (KGF), transforming growth factor-alpha (TGF-alpha), and their receptors in altered renal growth caused by complete ureteral obstruction in the developing kidney. Neonatal and adult rats underwent complete unilateral ureteral ligation or sham operation. The kidneys were harvested at 1, 5, 10, 20, and 30 days after obstruction. Renal growth and development was assessed by histology and immunohistocytochemical localization of vimentin, cytokeratin and smooth muscle-alpha actin. Cellular proliferation was measured by [3H]thymidine labeling index of all cells. RNase protection assays were used to quantify mRNA encoding for KGF, KGF receptor, TGF-alpha, and epidermal growth factor (EGF) receptor. Ureteral obstruction in the developing kidneys resulted in decreased DNA synthesis, rapid parenchymal loss, myofibroblast proliferation in the interstitium, decreased tubular epithelial cells formation, and development of cystic dysplasia. In comparison, obstruction in the mature kidneys resulted in transient growth in the medullary ductal cells, parenchymal loss, and myofibroblast proliferation at a later time, lymphocytic infiltration in the interstitium but not cystic dysplasia. KGF and KGF receptor mRNA levels were increased in obstructed neonatal kidneys. Similarly, TGF-alpha and EGF receptor mRNA levels were increased. Delayed and more moderate increases in KGF, KGF receptor, and TGF-alpha expression were also seen in the obstructed mature kidneys. Of importance, the amount of EGF receptor mRNA was not increased in the obstructed compared with the contralateral or sham-operated adult kidneys. This study suggests that obstruction alters the normal expression pattern of KGF, TGF-alpha, and their receptors in renal development. These changes may be responsible for the impaired renal growth and altered development seen in ureteral obstruction of the kidneys. Although some changes are similar to those seen in the adult kidney, the increased expression of TGF-alpha and cystic dysplasia are unique to neonatal obstruction.
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PMID:Growth factor expression in the obstructed developing and mature rat kidney. 1006 5

Cytokines have roles in tumor biology and induce neurological manifestations. Cytokines produced in response to a brain tumor may generate neurological manifestations via paracrine action. We investigated cytokine modulation in an in vivo brain tumor model with behavioral, morphological, and molecular approaches. Rat C6 glioma cells were implanted into the third cerebral ventricle of Wistar rats, their behavior was monitored, and the development of an intracranial tumor of astrocytic origin was confirmed by histology and positive immunostaining for vimentin, S-100 protein, and glial fibrillary acidic protein. Sensitive and specific RNase protection assays were used to analyze cytokine messenger RNA (mRNA) in brain regions from anorexic brain tumor-bearing animals. Brain tumor formation was associated with significant increased levels of interleukin (IL)-1beta, IL-1 receptor antagonist, IL-1 receptor type I, tumor necrosis factor (TNF)-alpha, and transforming growth factor (TGF)-beta1 mRNAs in the cerebellum, hippocampus, and hypothalamus. IL-1 receptor accessory proteins I and II mRNAs were increased in the cerebellum and hypothalamus. We also examined hypothalamic feeding-associated components: neuropeptide Y and proopiomelanocortin mRNAs were down-regulated, glycoprotein 130 mRNA levels were up-regulated, and leptin receptor (OB-R) mRNA levels were unchanged. These dissimilar profiles of mRNA expression suggest specificity of brain tumor-induced transcriptional changes. The data implicate cytokines as important factors in brain tumor-host interactions in vivo. The data also show that the C6 cell-induced glioma can be used as a behavioral-molecular model to study cytokine and neuropeptide modulation and action during the host biochemical and physiological responses to brain tumor development. Paracrine interactions seem pivotal because cytokine modulation was observed in various brain regions. These results also suggest that cytokine and neuropeptide changes during brain tumor progression are involved in brain tumor-associated neurological and neuropsychiatrical manifestations.
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PMID:Brain tumor development in rats is associated with changes in central nervous system cytokine and neuropeptide systems. 1035 67

Because the Wnt-4, -7b, and -11 genes are expressed in metanephric kidneys and code for secreted glycoproteins that may serve as mediators of the transformation of renal mesenchyme to epithelium, we investigated the pattern of Wnt gene expression in late metanephrogenesis and after ureteral obstruction. Newborn and 10-, 20-, and 60-day-old rats underwent complete unilateral ureteral ligation or sham operation. The kidneys were collected bilaterally 1, 5, 10, 20, or 30 days later. RNase protection assays were used to quantify the amounts of mRNA encoding Wnt-4, -7b, and -11, E-cadherin, and cytokeratin-19. Renal development was assessed by histologic characterization of vimentin, cytokeratin, E-cadherin, and beta-catenin distribution. During normal development, the amounts of mRNA encoding Wnt-4 and Wnt-11 increased during gestation and then abruptly decreased after the completion of metanephrogenesis, 15 days after birth. In contrast, the amounts of mRNA encoding Wnt-7b, E-cadherin, and cytokeratin-19 increased during development and into adulthood. In neonatally obstructed kidneys, the expression of Wnt-4 was abnormally maintained when obstruction was induced before the completion of renal development and was reactivated when obstruction was induced after the completion of metanephrogenesis. Wnt-7b expression was minimally affected and Wnt-11 expression was only transiently affected by obstruction. In neonatally obstructed kidneys, the differentiation of mesenchyme to epithelium failed to proceed normally, with the majority of cells maintaining vimentin expression and some differentiated epithelial cells reverting to vimentin expression. In addition, the expression of E-cadherin and cytokeratin was increased in epithelial cells. Changes in the expression of Wnt genes were correlated with histologic changes. This study suggests that Wnt-4 and -11 are likely to be important mediators of the transformation of mesenchyme to epithelium in the kidney. Obstruction induced during metanephrogenesis disrupts the normal pattern of Wnt-4, -7b, and -11 expression and interferes with the normal transformation process in developing kidneys, by maintaining the mesenchymal component and inducing the transformation of epithelium to mesenchyme.
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PMID:Expression of the Wnt gene family during late nephrogenesis and complete ureteral obstruction. 1037 7

First observed as components of non-translated mRNP complexes, prosomes harbour RNase and several proteinase activities; they are also the central constituent of the "Multicatalytic Proteinase (MCP) complexes" or "26S-proteasomes". In two recent publications (Arcangeletti et al., 1997b; De Conto et al., 1997) we have shown, by applying a new fixation technique, that these particles distribute differentially between the cytoskeletal networks of intermediate filament (IF) and actin types; previously they had been observed exclusively on the intermediate filaments. Here we further investigate the distribution of prosomes of several types, distinct by their subunit composition, between the IF of vimentin type and the actin network, as well as in the 3D space of the cell. It is shown that subtypes of prosomes occupy specific networks of the cytoskeleton, and that this pattern is specific for a given cell type. Confocal microscopy shows that prosome cytodistribution is not homogeneous in the 3D space: in the perinuclear area they colocalize most strongly with the IF, and more peripherally with the microfilament/stress fiber system; connections may exist between the two networks. Furthermore, new data indicate that the prosome-actin interaction may participate in the molecular structure of the stress fibers.
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PMID:Specific types of prosomes distribute differentially between intermediate and actin filaments in epithelial, fibroblastic and muscle cells. 1092 58


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