Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An apurinic/apyrimidinic (AP) endonuclease (E.C.3.1.25.2) has been purified 1100 fold to apparent homogeneity from calf thymus by a series of ion exchange, gel filtration and hydrophobic interaction chromatographies. The purified AP endonuclease is a monomeric protein with an apparent molecular weight on SDS-PAGE of 37,000. On gel filtration the protein behaves as a protein of apparent molecular weight 40,000. DNA cleavage by this AP endonuclease is dependent on the presence of AP sites in the DNA. DNA cleavage requires the divalent cation Mg2+ and has a broad pH optimum of 7.5-9.0. Maximal rates of catalysis occur at NaCl or KCl concentrations of 25-50 mM. The amino acid composition and the amino-terminal amino acid sequence for this AP endonuclease are presented. Comparison of the properties of this AP endonuclease purified from calf thymus with the reported properties of the human AP endonuclease purified from HeLa cells or placenta indicate that the properties of such an AP endonuclease are highly conserved in these two mammalian species.
 ...
PMID:Purification and amino-terminal amino acid sequence of an apurinic/apyrimidinic endonuclease from calf thymus. 244 59

Pairs of murine monoclonal antibodies, which recognize 2 different epitopes on a single antigen are described. These antibodies (MdT-P1, -P2, -Q1, -Q2) defining a canine pan-T cell antigen, were raised against dog thymocytes. In immunoblotting of solubilized and polyacrylamide gradient gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE) fractionated dog thymocytes, they revealed a strong heterogeneous antigen. Competitive inhibition of binding of directly labeled mouse-antidog T lymphocytes monoclonal antibodies (MdT-mAbs) to solubilized dog thymocytes indicates that 2 different antigenic epitopes (P, Q) are recognized. In indirect peroxidase immunocytochemistry, MdT monoclonal antibodies recognized up to 95% thymocytes, 69% blood lymphocytes, 76% lymph node lymphocytes, and approximately 2% bone marrow lymphocytes; they were nonreactive with surface immunoglobulin positive blood cells, monocytes, platelets, cells of myelo- and erythropoietic lineage in the bone marrow. Immunohistochemistry on thymus, lymph nodes, and spleen sections revealed that MdT-mAbs had labeled cortical and medullary thymocytes, paracortical T cell areas in lymph nodes and the periarteriolar zone of spleen white pulp, whereas B cell areas remained unstained. The antibodies lysed dog thymocytes in the presence of complement. Lethally irradiated dog receiving bone marrow autograft depleted of MdT-P1 positive cells ex vivo showed engraftment and complete recovery of marrow function. Studies of antibody activity on canine hemopoietic progenitor cells in granulocyte-macrophage progenitors (CFUGM) also showed no reduction of CFUGM in MdT-P1-depleted bone marrow.
 ...
PMID:Recognition of two epitopes of an antigen present on canine T cells but not on hemopoietic progenitors by four monoclonal antibodies. 244 51

The cytosolic untransformed molybdate-stabilized glucocorticoid-receptor complex from rat liver was eluted as a heterogenous peak containing two components with Stokes radii (Rs) of 8.3 nm and 7.1 nm when analyzed by size-exclusion HPLC even in the absence of molybdate. In contrast, the highly purified glucocorticoid receptor yielded a sharp symmetrical peak of Rs = 7.1 nm. We demonstrate that the 7.1-nm component could not result from a proteolytic degradation of the 8.3-nm receptor form. The same receptor heterogeneity was observed in thymus cytosol which contains less proteases than liver. After labeling with [3H]dexamethasone 21-mesylate and SDS/PAGE the same 94-kDa receptor band was revealed in both the 8.3-nm and 7.1-nm forms. Immunoblotting experiments showed that both the 94-kDa hormone-binding subunit and the 90-kDa heat-shock protein were present in the two different receptor forms. The 8.3-nm receptor form was converted to the 7.1-nm receptor form after treatment by ribonuclease A in the presence of molybdate and this effect was dose-dependent, being completely prevented by placental ribonuclease inhibitor (RNasin). In contrast, in the presence of molybdate, the 7.1-nm receptor form was ribonuclease-insensitive. Treatment of cytosol with RNase A in the absence of molybdate, partially shifted the untransformed receptor towards the 5.2-nm transformed receptor form. This effect was abolished by placental ribonuclease inhibitor. RNase S protein, an enzymatically inactive proteolytic fragment of RNase A, or S1 nuclease, which is specific for single-stranded nucleic acids, were ineffective when used instead of RNase A. In contrast, cobra venom endonuclease, which preferentially attacks double-stranded regions of small RNAs, caused a complete conversion of the 7-8-nm untransformed receptor to the 5.2-nm transformed receptor form. These results were not observed in the presence of molybdate. Addition of RNasin prior to heating cytosol in the absence of molybdate did not prevent the receptor from dissociating to the 5.2-nm form, suggesting that an endogenous RNase is not involved in the transformation process. The 7.1-nm receptor form was shifted to a 9.2-nm complex when incubated with an excess of GR 49 antireceptor antibody, whereas the 8.3-nm receptor form did not bind to the antibody.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:RNA binding to the untransformed glucocorticoid receptor. Sensitivity to substrate-specific ribonucleases and characterization of a ribonucleic acid associated with the purified receptor. 246 3

The primary structure of the zeta subspecies of rat brain protein kinase C was deduced from its overlapping cDNAs. The zeta subspecies of protein kinase C consists of 592 amino acid residues with the calculated molecular mass of 67,740 Da and has regulatory and protein kinase domains in its amino- and carboxyl-terminal halves, respectively. Although all members of the protein kinase C family so far identified have a tandem repeat of the characteristic cysteine-rich zinc-finger-like sequence in the regulatory domain, the zeta subspecies contains only one set of this sequence. Northern (RNA)-blot hybridization analysis indicated that two major RNA transcripts of the zeta subspecies with different lengths may be generated by the use of different polyadenylylational signals. The enzyme was expressed in COS-7 cells by transfection with the cDNA construct encoding its whole sequence. It showed an approximate molecular mass of 64,000 Da upon SDS/PAGE. The enzyme activity was significantly dependent on phospholipid but was independent of the presence of Ca2+ or diacylglycerol, when assayed with calf thymus H1 histone as a phosphate acceptor protein. The zeta subspecies expressed in COS-7 cells did not appear to show binding activity of phorbol ester. The structural and biochemical properties indicate that the zeta subspecies is related to, but distinct from, other subspecies of protein kinase C. Perhaps, this subspecies belongs to another entity of the enzyme family.
 ...
PMID:Protein kinase C zeta subspecies from rat brain: its structure, expression, and properties. 247 89

The cellular localization of glutathione-requiring PGD synthetase, which catalyzes the predominant formation of PGD2 in various peripheral tissues, was investigated in adult rats by immunoperoxidase-staining with a polyclonal antibody specific for this enzyme. Although the 25 N-terminal amino acid residues of synthetase are 56% identical and 76% similar to those of several rat glutathione S-transferase subunits, the antibody cross-reacted only with synthetase in dot blotting and was nearly completely inactive with all transferase isozymes thus far purified. In Western blotting after SDS-PAGE of crude extracts of rat spleen, the antibody showed a single positive band at the same position as that of the purified enzyme (Mr = 26,000). The positive immunocytochemical stain was found in a number of histiocytes and/or dendritic cells in spleen, thymus, and Peyer's patch of intestine. The immunostain was also observed in such cells in lamina propria of the villus in small intestine and colon, in submucosal layer of stomach, and in Kupffer cells in liver. Immunoelectron microscopy confirmed that immunoreactivity of this enzyme was distributed in cytoplasm of those cells. Such immunoreactive cells were not observed in brain, spinal cord, kidney, heart, testis, and skeletal muscle. These observations suggest that PGD2 is produced by glutathione-requiring PGD synthetase localized in these types of APC in various tissues and may play a critical role in dictating the progression of immune responses.
 ...
PMID:The major source of endogenous prostaglandin D2 production is likely antigen-presenting cells. Localization of glutathione-requiring prostaglandin D synthetase in histiocytes, dendritic, and Kupffer cells in various rat tissues. 250 61

The surface expression of CD3-associated TCR chains on hybridoma cell lines derived from adult gamma delta thymocytes was analyzed. These cell lines were unusual, in that a) they expressed a surface heterodimer consisting of a 40- and a 42-kDa chain, i.e., comprised of chains different from any previously reported gamma delta-TCR all of which express C gamma 1- or C gamma 2-encoded gamma-chains; b) their CD3-associated TCR could not be categorized as alpha beta-TCR dimers, despite the similarities in m.w. of the TCR chains, because full size 1.3-kb beta-chain mRNA capable of encoding a functional beta-chain could not be detected in these cells; c) neither of the receptor chains could be precipitated with anti-C gamma 1C gamma 2-peptide antisera. Biochemical analysis demonstrated that the 42-kDa delta-chain is a novel chain, which differs from any reported delta-chains in size, charge and number of glycosylation sites. Collectively, the data on analysis of the 40-kDa chain strongly suggest that it represents a gamma-chain encoded for by the C gamma 4 locus, protein products of which have not yet been reported in the thymus. This gamma-chain was also unique, in that its isoelectric point was much lower than that of other gamma-chains. The gamma- and delta-chains on these C gamma 4-expressing hybridomas were indistinguishable from one another in size and charge (as determined by nonequivalent pH gradient electrophoresis/SDS-PAGE analysis and analysis after endoglycosidase treatment). Because the cell lines were randomly chosen from large panels of hybridomas, these results may well imply strikingly nonrandom pairing of thymocyte-derived C gamma 4 chains and the delta-chains reported here. Thus, only limited additional gamma delta repertoire diversity may be generated by availability of this gamma delta-TCR in the thymus.
 ...
PMID:A novel gamma delta T cell receptor for antigen adds limited diversity to the gamma delta repertoire in adult thymus. 252 Dec 36

The superoxide-forming NADPH oxidase of resting macrophages can be activated in a cell-free system by certain anionic amphiphiles, most notably SDS. Activation requires the cooperation of membrane-associated and cytosolic components. We now report that at least two cytosolic factors are required for SDS-elicited activation of NADPH oxidase of guinea pig macrophages. Treatment of cytosol with ammonium sulfate at 37% saturation led to the partition of the two factors in the supernatant and precipitate fractions (termed components sigma 1 and sigma 2, respectively). Although each fraction by itself was inactive, recombining them resulted in complete recovery of the original ability of native cytosol to support SDS-elicited superoxide production by octyl-glucoside solubilized macrophage membranes. Both components are proteins, as shown by their susceptibility to trypsin and proteinase K, and were inactivated by heating at 60 degrees C. sigma 2, but not sigma 1, was inactivated by treatment with the covalent sulfhydryl reagent N-ethylmaleimide. On high-performance gel filtration, sigma 1 was found to have a molecular mass of 30 to 52 kDa, whereas sigma 2 eluted with molecules of 150 to 440 kDa. Component sigma 1 was partially purified from the ammonium sulfate supernatant fraction of cytosol by hydrophobic interaction chromatography followed by gel filtration. A material behaving like sigma 1 was also found to be present in the cytosol of guinea pig thymus cells, lymph node lymphocytes and brain and of the mouse myeloma cell line MOPC 315. However, sigma 2 appears to be strictly phagocyte specific. The molecular characteristics of sigma 1 components from nonphagocytic cells were similar to those of macrophage sigma 1, as shown by their presence in the supernatant, after treatment of cytosol with ammonium sulfate at 37% saturation, a molecular mass close to 30 to 52 kDa and a similar behavior on hydrophobic interaction chromatography. These findings raise the possibility that cytosolic component sigma 1 might be the bearer of a cellular function, more general than the one suggested by its role in the activation of NADPH oxidase of phagocytes.
 ...
PMID:Activation of the superoxide-forming NADPH oxidase of macrophages requires two cytosolic components--one of them is also present in certain nonphagocytic cells. 255 80

Ca2+,Mg2+-dependent nuclease was isolated from calf thymus chromatin by stepwise chromatography on DEAE-Sepharose, CM-Sephadex and DNA-Sepharose. The enzyme was purified more than 700-fold. SDS-PAGE electrophoresis revealed one protein band possessing an enzymatic activity. The molecular mass of the nuclease as determined by gel filtration is 25700 Da, that determined by 12% SDS polyacrylamide gel electrophoresis is 28,000 Da. In the presence of various ions the enzyme activity decreases in the following order: (Ca2+ + Mn2+) greater than (Ca2+ + Mg2+) greater than Mn2+; the pH optimum is at 8.0. In media with Mg2+, Ca2+, Co2+ and Zn2+ the nuclease is inactive. Some other properties of the enzyme are described.
 ...
PMID:[Isolation of Ca2+, Mg2+-dependent nuclease from calf thymus chromatin]. 260 72

Immunofluorescent analysis with antibodies against histone H1 failed to detect H1 in the centromeric heterochromatin blocks of the polytene chromosomes of Glyptotendipes barbipes larvae. Centromeric regions were dissected microsurgically and acid-extracted. Electrophoresis in SDS and acid-urea gels revealed a band comigrating with H1 of calf thymus and of Gl. barbipes salivary gland nuclei. ELISA dot assay of the extracted material gave a positive reaction with anti-H1 monoclonal antibodies and with anti-H1 affinity-purified polyclonal antibodies. This shows that the centromeric heterochromatin contains histone H1 but packed in a way which prevents the H1 antigenic determinants from reacting in situ with the specific antibodies.
 ...
PMID:Histone H1 in the centromeric heterochromatin of Glyptotendipes barbipes larval polytene chromosomes. 267 Apr 83

Anti-thymus microsome antibodies and anti-skeletal muscle microsome antibodies in sera from patients with myasthenia gravis (MG) were analyzed by means of immunoblotting, which was performed after SDS polyacrylamide gel electrophoresis of antigens to clarify the pathogenic role of the thymus in MG. Anti-thymus microsome antibodies were detected in 15 of the 20 cases of MG examined. The detection frequency (75%) was significantly higher than the corresponding frequency determined for anti-muscle microsome antibodies (35%) in the same group of patients. Thymic antigens with a molecular weight of 38 kilodaltons (KD), 60 KD and 220 KD were often recognized by antibodies in sera from MG patients studied here. The anti-thymus microsome antibodies were not cross-reactive with either thymic acetylcholine receptors or lymphocyte surfaces. These findings indicated that the specific antibodies were produced to the thymic microsomal fraction, and its frequency was higher than has been suspected in MG patients.
 ...
PMID:Electrophoretic immunoblotting analysis of anti-thymus microsome antibodies in patients with myasthenia gravis. 271 26


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>