By ion-exchange chromatography, the existance of Ribonuclease from Vietnam’s black cobra. Venum in multiple molecular forms was confirmed. Its two separated peaks were noted on CM-cellulose column chromatography. At present , the nature of these RNase chromatographic forms are unknown, but it is probably that they possess quaternary structure
Ribonucleases ; Venoms ; Snakes

In the study, using the kinetic method for the examination of the dependence between the specific activity of the enzyme and the concentration of the enzyme itself in the combined reaction, the researchers have proved that the Ribonuclease (R.Nase) molecule of the black cobra (Naja naja) venom exits at least in two interconvertible forms with the difference in specific activity of almost one grade. These two forms are probably the different oligomers or configurations, temporarily named as the kinetic forms of R.Nase found in the black cobra venom.
Snake Venoms ; Ribonucleases ; Polymorphism, Genetic

Evaluate the influences of some factors as enzyme level, the time of diluting enzyme solution, substrate level and temperature on pH value of RNase from Vietnam Cobra (Naja naja) venom. Results: the changes of pH value for cobra venom RNase can be depended on concentrations of the enzyme and substrate. This variation in the pH value of the enzyme can be explained by existence of this RNase as an enzyme system composed of some interconvertible forms. The interconversion between these enzyme forms is very slow process (counting by hours) in comparison with the rate of reactions
Cobra ; Hydrogen-Ion Concentration ; Ribonucleases

Enzyme activities of Cenococcum geophilum isolates were examined on enzyme-specific solid media. Deoxyribonuclease, phosphatase, and urease were detected in all isolates, whereas cellulase was not detected in any of the isolates. Variations in enzyme activities of amylase, caseinolysis, gelatinase, lipase, and ribonuclease were observed among isolates.
Amylases ; Cellulase ; Gelatinases ; Lipase ; Ribonucleases ; Urease

BACKGROUND: There were few data on the gene mutations involved in the development of basal cell carcinoma(BCC) in Korean. OBJECTIVE: To gain insight into the role of p53 gene mutations of BCC in Koreans. METHODS: Fifteen BCCs were screened for mutation of the p53 gene. Immunohistochemical staining was done on the paraffin sections using a labelled streptavidin-biotin-peroxidase complex method with the primary antibody against p53 protein. Analysis of p53 mutation was done by non-isotopic RNase cleavage assay and direct sequencing. RESULTS: Mutation of p53 gene was found in 40%(6/15) of the cases. One case showed mutations in exon 6, one in exon 6 and intron 8, two in exon 8, one in exon 9, and one in intron 5. But ultraviolet specific C->T change was detected in only one case. Immunohistochemical expression of p53 was seen in 40%(6/15), but its expression did not coincide with p53 gene mutation. CONCLUSION: Ultraviolet specific mutations of p53 were much less frequent in Korean than in Caucasian, suggesting other etiologies than ultraviolet radiation.
Carcinoma, Basal Cell* ; Exons ; Genes, p53* ; Humans ; Introns ; Paraffin ; Ribonucleases

It is well known that HL-60 cell, a human promyelocytic line, is differentiated into eosinophil-like cells in the presence of butyric acid, and thus the differentiated HL-60 cells have been used as a model system to study irnmunological properties of peripheral eosinophils which are thought to be terminally differentiated. To study whether HL-60 cells alter their capability of expressing cytokines during differentiation to eosinophil-like cells, we examined TNF mRNA levels in HL-60 cells treated with butyric acid by Ribonuclease Protection Assay (RPA). HL-60 cells were incubated for 3 days in the presence of butyric acid (0.5 mM), and stimulated with PMA and lipopolysaccharide (LPS). The levels of TNF mRNA decreased by 50 % and 95 % upon one and two days of post-treatment of butyric acid, respectively. The decreased pattern in TNF mRNA levels was also observed in HL-60 cells that have been treated with retinoic acid known as an inducer for differentiation of them. In accordance with these results, prominent azurophilic granules typical in eosinophils appeared in the cytoplasm of the differentiated HL-60 cells. The decreased expression of TNF mRNA was not attributable to the presence of serum, since increasing concentrations of serum had no effect. Furthermore, interleukin-5 (IL-5), which is known to be involved in activation and trafficking of eosinophils in vivo and in vitro, failed to affect TNF mRNA production when it was used in place of butyric acid. These data suggest that the differentiated HL-60 cells may have immunological resemblance to eosinophils in that they weakly produce the cytokine mRNA.
Butyric Acid ; Cytokines ; Cytoplasm ; Eosinophils ; HL-60 Cells* ; Humans ; Interleukin-5 ; Ribonucleases ; RNA, Messenger* ; Tretinoin

This experiment is designed to find differentially expressed genes in p388D1 cells that are specific for the serum deprived state. Serum starvation induces cells to enter the quiscent state in the cell cycle and is used to arrest cell growth or synchronize the cell cycle. Differential display and ribonuclease protection assay were used to identify quantitative change in gene expression. Nineteen genes that showed a differential expression in the differential display were cloned and 7 clones were verified by a ribonuclease protection assay. Among the 7 clones clone-16 showed same expression pattern in comparison with the differential display. Deduced amino acid sequences of clone-16 had N-glycosylation motif and seems to be a secretory protein. Getting a full sequence of clone-16 is critical for the characterization of it.
Amino Acid Sequence ; Cell Cycle ; Clone Cells ; Gene Expression ; Ribonucleases ; Starvation

PURPOSE: The aim of the present study was: (a) to determine the frequency of p53 mutations by single strand conformational polymorphism analysis of polymerase chain reaction products (PCR-SSCP), Non-Isotopic RNase Cleavage Assay (NIRCA) and immunohistochemical staining with monoclonal antibody; and (b) to compare the correlations among these methods. MATERIALS AND METHODS: Abberations of the p53 gene in 24 primary gastric carcinomas were examined by PCR-SSCP, NIRCA and immunohistochemical staining. Of these surgically resected gastric adenocarcinomas, 23 were advanced gastric carcinomas and 1 was early gastric cancer. Using PCR-SSCP and NIRCA, the presence of mutations in exons 4-9 was evaluated. Using the mouse specific anti-human p53 monoclonal antibody, we also looked for overexpression of the p53 protein in tissue sections. RESULTS: In 5 cases shifted bands were reproducibly identified by PCR-SSCP, and two mutations were identified in exon 4 and three in 5 & 6. The mutations of exon 4 were detected by NIRCA in 5 cases, exon 5 & 6 in 6 cases, and exon 7 in 2 cases. The p53 mutations detected by PCR-SSCP were also detected by NIRCA except one case. Thirteen of the tumor samples were positively stained with the monoclonal antibody for p53 protein. There was no correlation between p53 mutations detected by NIRCA and expression of p53 protein by immunohistochemical staining. CONCLUSIONS: Our results in this group of patients suggest that NIRCA is more sensitive than PCR-SSCP in detecting p53 mutations, and expression of p53 protein by immunohistochemical staining does not directely represent the genetic changes of p53 gene.
Adenocarcinoma ; Animals ; Exons ; Genes, p53* ; Humans ; Mice ; Polymerase Chain Reaction ; Ribonucleases* ; Stomach Neoplasms*

An RNase P ribozyme library has been developed as a tool for functional genomics studies. Each clone of this library contains a random 18-mer and the sequence of M1 RNA, the catalytic subunit of RNase P. Repression of target gene expression is thus achieved by the complementary binding of mRNA to the random guide sequence and the successive target cleavage via M1 RNA. Cellular expression of the ribozyme expression was confirmed, and EGFP mRNA was used as a model to demonstrate that the RNase P ribozyme expression system can inhibit the target gene expression. The constructed RNase P ribozyme library has a complexity of 1.4x10(7). This novel library system should become a useful in functional genomics, to identify novel gene functions in mammalian cells.
Catalytic Domain ; Clone Cells ; Gene Expression ; Genomics* ; Repression, Psychology ; Ribonuclease P* ; Ribonucleases* ; RNA ; RNA, Messenger

BACKGROUND: The Angiopoietin-1 (Ang1), Angiopoietin-2 (Ang2) and Tie2 have essential role in angiogenesis in development. Ang1 and Ang2 are ligands which binds to their receptor, Tie2. METHODS: Expression of these proteins was sought during mouse kidney maturation from embryonic day 16 (E16) to 28 days postnatal (P28). RESULTS: Using RNase protection assay and Western blot, these three molecules were expressed throughout the experimental period with peak levels at P28 (Ang1), P14 (Ang2) and P7 (Tie2). By immunohistochemical analysis, Ang1 protein was found to localize to condensing renal mesenchymal cells, and tubules. Ang2 proteins were detected in differentiating outer medullary tubules and the vasa recta bundle area. Tie2 protein was detected in a portion of glomerular tufts and cortical interstitium, and medulla including vessels in the vasa recta. CONCLUSIONS: These data suggest that Ang1, Ang2 and Tie2 proteins are expressed in renal development.
Angiopoietin-1* ; Angiopoietin-2* ; Animals ; Blotting, Western ; Kidney* ; Ligands ; Mice* ; Receptor, TIE-2 ; Ribonucleases