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PubMed2005

[Monitoring CML28 mRNA levels in patients before and after HSCT by real-time quantitative RT-PCR].

The purpose of this study was to establish a SYBR Green I real-time quantitative RT-PCR method for investigating the correlation between CML28 mRNA expression levels and relapse of leukemia after allo-hematopoietic stem cell transplantation (HSCT). pcDNA3.1HisA-CML28 plasmid had been constructed as the standard template. Serial monitoring of CML28 mRNA levels by SYBR Green I real-time quantitative RT-PCR technique was performed in 14 patients, including 10 patients with CML and 3 patients with AML, 1 patient with Ph(+) ALL. The results showed that the sensitivity of the established method was at 10(-4) (0.05 ng) level, with interassay variation and intraassay variation of standard samples both below 10%. The CML28 was highly expressed in AML and CML-BP or AP. CML28 level in newly diagnosed group was (6.58 +/- 2.34) x 10(-2), in pre-conditioning regimen group was (2.19 +/- 0.32) x 10(-2), in group that 1 month after HSCT was (1.35 +/- 1.28) x 10(-2), in group that 3 months after HSCT was (4.57 +/- 6.39) x 10(-3). CML28 can be detected 3 months after HSCT in 1 patient with CML-CP and 3 patients with CML-AP or BC. 2 of them with low level (<2 x 10(-2)) survived without relapse, the other 2 case with high level (>2 x 10(-2)) relapsed within one year, 1 case died and 1 case received the second time HSCT, CML28 level decreased rapidly after HSCT, but still higher than 2 x 10(-2) and relapse has taken place. The conclusions was made that CML28 mRNA level is obviously correlated with the development of leukemia. Serial quantification of CML28 mRNA levels are necessary for HSCT recipients, and more informative than a single detection. Using of this assay to evaluate MRD in the patients received HSCT is helpful for prediction of relapse.

Adolescent↗
PubMed1991

Monitoring bovine viral diarrhea virus vaccines for adventitious virus, using T1 ribonuclease viral RNA oligonucleotide fingerprinting.

Viral RNA oligonucleotide fingerprinting was used to discriminate 3 cytopathic vaccine bovine viral diarrhea viruses (BVDV) grown in medium supplemented with serum contaminated with noncytopathic BVDV from the same 3 viruses grown in cell culture free of BVDV. Oligonucleotide fingerprinting also effectively discriminated between reference Singer BVDV, NADL BVDV, and New York-1 BVDV grown in BVDV-free noncontaminated or BVDV-contaminated cell cultures. Oligonucleotide fingerprint mapping of viral RNA maybe used to determine the purity of virus stocks, as well as that of BVDV vaccines.

Animals↗
PubMed2006

Childhood onset systemic sclerosis: classification, clinical and serologic features, and survival in comparison with adult onset disease.

OBJECTIVE: To describe the differences between patients with systemic sclerosis (SSc) having childhood versus adult onset evaluated at a single medical center. METHODS: Patients were divided into those with childhood onset (first SSc symptom or finding before age 16 yrs) and those with early adult and late adult onset. The 3 groups were compared with respect to disease classification, clinical, laboratory and serologic data, and survival. RESULTS: One hundred eleven childhood onset SSc cases seen between 1960 and 2003 were compared with 2559 adult onset SSc cases (1087 with onset age 16-40 and 1472 with onset after age 40 yrs) first evaluated between 1972 and 2001. Age distribution at onset was unimodal, suggesting that childhood disease is part of the spectrum of adult onset SSc. A significantly greater proportion of childhood onset patients had overlap syndromes, most frequently with polymyositis-dermatomyositis (PM-DM), and skeletal muscle involvement. Children with diffuse cutaneous (dc) SSc had significantly lower maximum mean total skin thickness scores than adult patients with dcSSc. Renal involvement was uncommon in childhood onset cases, and the frequency increased with age of onset. Serum anti-PM-Scl and anti-U1RNP antibodies were detected significantly more frequently in childhood than in adult onset cases. In contrast, anti-RNA polymerase III and anticentromere antibodies were found significantly more frequently in adults. Survival was significantly better among childhood than all adult onset cases combined, but similar to survival in young adult onset SSc cases. Scleroderma heart disease was a frequent cause of death among children with SSc. CONCLUSION: Patients with juvenile onset SSc more frequently have an overlap syndrome with PM-DM, higher frequency of skeletal muscle involvement, serum anti-PM-Scl and anti-U1RNP antibody, fatal cardiac disease, and improved survival compared with adult onset SSc cases.

Adult↗
PubMedDate not supplied

EGF receptor-related protein (ERRP) inhibits invasion of colon cancer cells and tubule formation by endothelial cells in vitro.

Activation of the epidermal growth factor receptor (EGFR) and/or its family member(s) stimulates many processes of carcinogenesis, including cell invasion and the formation of new blood vessels, events that are critically involved in angiogenesis. Interference with the activation of EGFRs, therefore, represents a promising strategy for the development of novel and selective anticancer therapies. Previously, we reported that EGFR-related protein (ERRP), which we have isolated and characterized as a pan-erbB inhibitor, is a potential therapeutic agent for colorectal and other epithelial cancers. The present investigation was undertaken to determine whether ERRP would affect the invasion of colon cancer cells and formation of tubules, and the regulation of these processes. ERRP inhibited tubule formation by aortic endothelial cells and invasion of HCT-116 colon cancer cells through matrigel. These changes were associated with marked reductions in the synthesis and secretion of bFGF, VEGF and TGF-alpha by HCT-116 cells. Secretion of bFGF and VEGF by aortic endothelial cells was also inhibited by ERRP. Microarray analysis of ERRP-treated HCT-116 cells showed reduced levels of several growth regulatory proteins such as p21Rac1, Stratifin (14-3-3 Sigma), focal adhesion kinase (FAK) and mediators of the Ras-Raf-ERK pathway. ERRP treatments resulted in reduced expression of p21Rac1 and inhibited the constitutive activation of FAK and MEK2 in HCT-116 cells. Transfection of constitutively activate p21Rac1 or MEK2 into HCT-116 cells abrogated ERRP-induced inhibition of growth. In summary, it was demonstrated that ERRP not only inhibits cell growth, but also the processes of cell invasion and blood vessel formation that are critical for the development and progression of carcinogenesis.

14-3-3 Proteins↗
PubMedDate not supplied

Immunohistochemical expression of 14-3-3 sigma protein in intraductal papillary-mucinous tumor and invasive ductal carcinoma of the pancreas.

BACKGROUND: 14-3-3 sigma (sigma) has been shown to be overexpressed in pancreatic cancers by a c-DNA microarray technique. However, the expression of 14-3-3 sigma in intraductal papillary-mucinous tumor (IPMT) of the pancreas remains unclear. MATERIALS AND METHODS: To evaluate the biological importance of 14-3-3 sigma expression in pancreatic carcinogenesis, immunohistochemistry for 14-3-3 sigma, CDX2, MUC1, MUC2, p53, p16 and Ki-67 was carried out on 33 IPMTs and the results were compared with those for 14 invasive ductal carcinomas (IDCs). RESULTS: The frequency of 14-3-3 sigma immunoreactivity was 70% and 100% in IPMT and IDC, respectively. The frequency of MUCI and Ki-67 immunoreactivity was significantly higher in IDC than IPMT. In IPMT, dark columnar cell types prevailed over clear columnar cell types in terms of the frequency of the Ki-67 labeling index. CONCLUSION: The overexpression of 14-3-3 sigma was confirmed in both IDC and IPMT. Therefore, this overexpression might occur in the early stages of pancreatic carcinogenesis. Moreover, IPMT composed of dark columnar cells might be a potentially more advanced form than that made up of clear columnar cells.

14-3-3 Proteins↗
PubMed2006

Promoter hypermethylation of the 14-3-3 sigma, SYK and CAGE-1 genes is related to the various phenotypes of urinary bladder carcinomas and associated with progression of transitional cell carcinomas.

To explore the significance of epigenetic mechanisms in urinary bladder carcinogenesis mediated by methylation of cytosine in CpG dinucleotides at 5' promoter regions, we analysed the methylation status of a broad panel of different genes in transitional cell carcinomas (TCC) and nonurothelial cancers, among which the 14-3-3 sigma, SYK and CAGE-1 genes were recognised as promising target genes. Using methylation-specific PCR, the rate of DNA hypermethylation proved to be related to the various histopathological cancer subtypes. The higher frequency of promoter methylation of the 14-3-3 sigma (57.1%) and SYK (64.3%) genes in high-grade, high-stage TCC in association with a reduced or even lacking immunohistochemical protein expression than in low-grade, low-stage TCC (28.6% and 42.9%, respectively), indicates that aberrant methylation of these genes plays an essential role in the progression of TCC. The importance of DNA hypermethylation in the conversion of TCC from a low to a high malignant potential was strongly supported by the finding that, unlike superficial low-grade TCC, advanced muscle invasive TCC showed a concurrent promoter methylation of the 14-3-3 sigma, SYK and CAGE-1 genes. Squamous cell carcinomas revealed a peak incidence of hypermethylation of the 14-3-3 sigma gene (80%), and conversely, the lowest methylation frequency of the SYK gene (13.3%). Undifferentiated small cell carcinomas disclosed a promoter methylation of the 14-3-3 sigma, SYK and CAGE-1 genes in only a quarter each for the cases. Although a correlation between the methylation status and gene activity in squamous cell and undifferentiated small cell carcinomas was not observed, the underexpression of the SYK protein products in both cancer types and additionally of the 14-3-3 sigma protein in small cell carcinomas appeared to be related to the aggressive clinical behaviour of both these nonurothelial bladder carcinomas. The relevance of the high frequency of DNA hypermethylation of the CAGE-1 antigen in TCC and squamous cell carcinomas merits further study, particularly in relation to anticancer immunotherapy. The methylation status of the PTEN, COX-2, RUNX-3 and HIC-1 genes was found to be unaltered. In conclusion, the different patterns of aberrant methylation of the 14-3-3 sigma, SYK and CAGE-1 genes in the various histopathological cancer types of the urinary bladder point to a role in tumor cell differentiation, resulting in the phenotypical conversion of TCC into nonurothelial carcinomas and in the progression of TCC to a more malignant potential.

14-3-3 Proteins↗
PubMed1991

Strand exchange protein 1 from Saccharomyces cerevisiae. A novel multifunctional protein that contains DNA strand exchange and exonuclease activities.

Strand exchange protein 1 (Sep1) from Saccharomyces cerevisiae catalyzes the formation of heteroduplex DNA molecules from single-stranded circles and homologous linear duplex DNA in vitro. Previously, Sep1 was purified as a 132,000-Da species; however, DNA sequence analysis indicates that the SEP1 gene is capable of encoding a 175,000-Da protein (Tishkoff, D.X., Johnson, A.W., and Kolodner, R.D. (1991) Mol. Cell. Biol. 11, 2593-2608). The SEP1 gene was cloned into a GAL10 expression vector and expressed in a protease-deficient yeast strain. Intact Sep1, which migrated as a Mr-160,000 polypeptide during sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was purified to apparent homogeneity and shown to have activities similar to those of the originally purified Mr = 132,000 fragment. We report here that, in addition to strand exchange activity, Sep1 contains an intrinsic exonuclease that is active on single- and double-stranded DNA with a severalfold preference for single-stranded DNA. The nuclease was induced in crude extracts upon induction with galactose, it co-purified with the strand exchange activity of Sep1, and the nuclease and strand exchange activities of Sep1 showed the same kinetics of heat inactivation. Sep1 nuclease, which requires Mg2+, can be functionally separated from the strand exchange activity by the substitution of Ca2+ for Mg2+. Under these conditions, the nuclease is inactive, and strand exchange activity is dependent on prior resection of the DNA ends by an exogenous exonuclease. Thus, the nuclease is necessary for synapsis but not strand exchange. Electron microscopic analysis revealed that true strand exchange products, alpha molecules and nicked double-stranded circular molecules, were formed. In addition, strand transfer proceeded to similar extents on 5'-resected and 3'-resected DNA. This result suggests that the polarity of strand transfer by Sep1 is determined by the polarity of its intrinsic nuclease.

Amino Acid Sequence↗
PubMedDate not supplied

Effect of acute ethanol consumption on hepatic lysosomal enzymes and calcium concentration during rat liver regeneration.

Effect of alcohol consumption on the activity of two lysosomal nucleases, deoxyribonuclease II (DNAase II) and ribonuclease II (RNAase II) and calcium concentration have been studied during liver regeneration of Sprague-Dawley rats over a period of 10 days following 70% partial hepatectomy. Liver weight was completely restored in partially hepatectomized rats at 8 days in both sexes, but ethanol treatment resulted in only a partial restoration of liver weight at 10 days. Specific activity of DNAase II in partial hepatectomized animals increased by 50-75% at 6-12 hrs above sham operated controls, and the specific activity of RNAase II increased 2.3 fold at 6 hr, while calcium concentration decreased by 50% at 6-12 hrs. Ethanol treatment masked and/or delayed the increase in the specific activity of both enzymes at early stages of liver regeneration and also masked the decrease in calcium concentration. These results indicate that ethanol consumption delays the process of liver regeneration by altering the activity of lysosomal nucleases and calcium concentration.

Alcohol Drinking↗
PubMed1990

DNA primase stimulatory factor from mouse FM3A cells has an RNase H activity. Purification of the factor and analysis of the stimulation.

Two forms of DNA primase stimulatory factor have been purified from mouse FM3A cells and shown to have RNase H activity. One of the factors, which consists of three polypeptides of 42,000, 41,000, and 27,000 daltons, was characterized in its properties as RNase H and DNA primase stimulatory factor. The nucleolytic activity of the factor specifically digested the RNA component of RNA-DNA hybrids in an endonucleolytic manner. The stimulation by the factor was observed in DNA synthesis by DNA primase-DNA polymerase alpha complex on unprimed DNA templates, and the DNA chains synthesized under these conditions in the presence of the factor were much shorter than those synthesized in its absence. The stimulatory effect of the factor on DNA primase activity was directly confirmed with DNA primase dissociated from DNA polymerase alpha by the observation of the increase in the number of synthesized oligoribonucleotides. The primer RNA synthesis by DNA primase-DNA polymerase alpha complex under the condition where DNA synthesis occurred was also significantly stimulated by the factor. Furthermore, under these conditions RNA primers were removed from DNA chains by the RNase H activity of the factor.

Animals↗
PubMed1985

[Mechanisms of the regulation of the biological activity of the cell by 2',5-oligoadenylate].

The problems of regulation of biological activity of the cell, in particular, of such complicated processes as cell growth, differentiation, etc., rank highest among the most burning problems of present-day biology. A great majority of regulatory systems have been discovered, which control the biological activity of the cell. Among those, a most multifunctional and thoroughly investigated one is the cAMP system. The mechanisms of cAMP-dependent regulation, cAMP-dependent enzymes and other aspects of the system function have become the subject of numerous experimental papers, reviews and monographs. Another regulatory system which presently attracts the wide attention of investigators is the 2',5'-oligoadenylate system. The aim of the present review is to summarize the current data on the action mechanism and biological significance of 2',5'-oligoadenylate. Besides, the authors analyze some experimental results concerning the mechanisms of interaction and mutual regulation of the two above-mentioned systems.

2',5'-Oligoadenylate Synthetase↗
PubMed1989

Rat nucleolar 7-2 RNA is homologous to mouse mitochondrial RNase mitochondrial RNA-processing RNA.

7-2 RNA (also termed RNA M and 7SM RNA) is a noncapped small RNA present in small ribonucleoprotein particles; these particles are present in the granular compartment of the nucleolus. Some sera from patients with scleroderma specifically immunoprecipitate 7-2 RNA-containing particles (Hashimoto, C., and Steitz, J. A. (1983) J. Biol. Chem. 258, 1379-1382; Reddy, R., Tan, E. M., Henning, D., Nohga, K., and Busch, H. (1983) J. Biol. Chem. 258, 1383-1386; Reimer, G., Raska, I., Scheer, U., and Tan, E.M. (1988) Exp. Cell Res. 176, 117-128). In this study, the primary sequence of Novikoff hepatoma 7-2 RNA was determined and a possible secondary structure is presented. The Novikoff hepatoma 7-2 RNA is 94% homologous to the recently described mouse mitochondrial RNase MRP RNA, suggesting that Novikoff hepatoma 7-2 RNA may be the homologue of mouse MRP RNA. The presence of 7-2 RNA in nucleoli and in mitochondria suggests that 7-2 ribonucleoproteins, in addition to being essential components of mitochondrial RNase, may also be functional in nucleolar RNA processing and ribosome biogenesis.

Animals↗
PubMed1989

Conformational stability and activity of ribonuclease T1 and mutants. Gln25----Lys, Glu58----Ala, and the double mutant.

Ribonuclease T1 (RNase T1) and mutants Gln25----Lys, Glu58----Ala, and the double mutant were prepared from a chemically synthesized gene, cloned and expressed in Escherichia coli. The wild-type RNase T1 prepared from the cloned gene was identical in every functional and physical property examined to RNase T1 prepared from Aspergillus oryzae. Urea and thermal unfolding experiments show that Gln25----Lys is 0.9 kcal/mol more stable and Glu58----Ala is 0.8 kcal/mol less stable than wild-type RNase T1. In the double mutant, these contributions cancel and the stability does not differ significantly from that of wild-type RNase T1. For the double mutant, the dependence of delta G on urea concentration is significantly greater than for wild-type RNase T1 or the single mutants. This suggests that the double mutant unfolds more completely in urea than the other proteins. The activity of Gln25----Lys is identical with that of wild-type RNase T1. The activities of Glu58----Ala and the double mutant are 7% of wild-type when GpC hydrolysis is measured (due to a 35-fold decrease in kcat), and 37% of wild-type when RNA hydrolysis is measured. Thus, Glu58 is important, but not essential to the activity of RNase T1.

Aspergillus oryzae↗
PubMed1989

Conformational stability and mechanism of folding of ribonuclease T1.

Urea and thermal unfolding curves for ribonuclease T1 (RNase T1) were determined by measuring several different physical properties. In all cases, steep, single-step unfolding curves were observed. When these results were analyzed by assuming a two-state folding mechanism, the plots of fraction unfolded protein versus denaturant were coincident. The dependence of the free energy of unfolding, delta G (in kcal/mol), on urea concentration is given by delta G = 5.6 - 1.21 (urea). The parameters characterizing the thermodynamics of unfolding are: midpoint of the thermal unfolding curve, Tm = 48.1 degrees C, enthalpy change at Tm, delta Hm = 97 kcal/mol, and heat capacity change, delta Cp = 1650 cal/mol deg. A single kinetic phase was observed for both the folding and unfolding of RNase T1 in the transition and post-transition regions. However, two slow kinetic phases were observed during folding in the pre-transition region. These two slow phases account for about 90% of the observed amplitude, indicating that a faster kinetic phase is also present. The slow phases probably result from cis-trans isomerization at the 2 proline residues that have a cis configuration in folded RNase T1. These results suggest that RNase T1 folds by a highly cooperative mechanism with no structural intermediates once the proline residues have assumed their correct isomeric configuration. At 25 degrees C, the folded conformation is more stable than the unfolded conformations by 5.6 kcal/mol at pH 7 and by 8.9 kcal/mol at pH 5, which is the pH of maximum stability. At pH 7, the thermodynamic data indicate that the maximum conformational stability of 8.3 kcal/mol will occur at -6 degrees C.

Exoribonucleases↗
PubMedDate not supplied

[Study of 2'-phosphodiesterase activity in cultured NIH 3T3 cells during activation of cAMP-dependent phosphorylation].

A rapid and transient decrease in 2'-phosphodiesterase activity in NIH 3T3 mouse cells was observed after adrenaline addition. The decrease of activity was accompanied by an elevation of intracellular cAMP level. The 2'-phosphodiesterase activity changed similarly when cells sink deeper into the resting state. In the latter case, the fall of the enzyme activity was correlated with elevation of the activity of cAMP-dependent proteinkinase and, moreover, a considerable increase of the intracellular level of 2',5'-oligoadenylate was observed. Phosphorylation of proteins by cAMP-dependent proteinkinase in the cell lysate also produced a pronounced drop of 2'-phosphodiesterase activity. Exogenous 2',5'-oligo (A) treatment of the cells resulted in the rise of 2'-phosphodiesterase activity; actinomycin D prevented this effect. The data presented suggest the involvement of two different mechanisms in regulation of 2'-phosphodiesterase activity: cAMP-dependent phosphorylation and induction of 2'-phosphodiesterase by 2',5'-oligoadenylate.

2',5'-Oligoadenylate Synthetase↗
PubMed1987

Purification and characterization of a 2'-phosphodiesterase from bovine spleen.

Interferon-induced 2',5'-oligoadenylates are transiently produced during viral infection and are believed to play a role in the interferon-mediated inhibition of replication of at least some viruses. 2',5'-Oligoadenylates must be catabolized but are resistant to degradation by most known ribonucleases. A 2'-phosphodiesterase that degrades 2',5'-oligoadenylates was purified 1500-fold from a low speed homogenate of bovine spleen by precipitation at pH 5.2, ammonium sulfate fractionation, differential ultrafiltration, and successive chromatography on DEAE-Sephacel, hydroxylapatite, and a fast protein liquid chromatography Mono P column. No other 2-5A-degrading activity was observed during the purification procedure. The molecular mass of the enzyme estimated by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 65,000. The enzyme is distinct from bovine spleen phosphodiesterase II. The 2'-phosphodiesterase cleaves 2',5'- and 3',5'-linked oligonucleotides, as well as branched oligoadenylate, A(2'pA)(3'pA), but appears to be most active on 3',5'-oligoribonucleotides. The enzyme cleaves 5'-AMP from the 2' terminus of 2',5'-oligoadenylates and appears to require a free 2' terminus and a 3'-oxygen on the penultimate nucleotide. Substrate length, 5'-phosphorylation, and base composition do not appear to be critical factors in determining enzyme activity. The effects of pH, Mg2+, Mn2+, EDTA, phosphate, 2-mercaptoethanol, and N-ethylmaleimide are also described. This enzyme may be involved in the catabolism of the interferon-induced 2',5'-oligoadenylates and other 2',5'-linked RNAs in the cell.

Animals↗
PubMedDate not supplied

[Spectrofluorimetric detection of two states during melting of ribonuclease T1].

The melting temperature of ribonuclease T1 was studied by the fluorescent method. It was shown that in the melting region the tryptophanyl fluorescence spectrum of the protein containing a single tryptophanyl is the sum of two simple spectra typical for tryptophanyl located in the hydrophobic environment and for tryptophanyl completely accessible to aqueous solvent, correspondingly. This implies the evidence of two forms of the protein, i.e. native (folded) and denatured (unfolded), in the transition region. No intermediate states were found in measured quantities. Therefore, ribonuclease T1 melting process corresponds to the two states model. The free energy of native structure stabilization of the protein at room temperature is delta G approximately equal to 37 kJ/mol.

Aspergillus↗