Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009443 (cold)
 92,137 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The preliminary phytochemical screening of the two seeds established the presence of carbohydrates and/or glycosides, flavnoids, unsaturated sterols and/or triterpenes, saponins, trypsin inhibitors and haemagglutinins. In addition, it established the absence of cardenolides, tannins, alkaloids and oxidase enzyme. 2. Certain pharmacopoeial constants, including moisture, ash, acid-insoluble ash, water-soluble ash and crude fibre were determined. 3. The two seeds were subjected to successive extractions with different organic solvents such as petroleum ether (50-70 degrees C), diethyl ether, chloroform and ethyl alcohol. The successive yields of extractives were determined. Examination of the crude extracts showed that petroleum ether extract contained sterols and/or triterpenes, while ether, chloroform, and ethyl alcohol extracts contained reducing substances. 4. General analysis of the two seeds for proteins, fats, carbohydrates, fibre and ash contents were carried out and the results were given in g/100 g dry seeds. Pigeon pea contained 25.2 g protein, 170 mg calcium and 8.9 mg iron. The protein content of kidney bean was 23 g, while calcium and iron contents were 134 mg and 8.02 mg respectively. 5. Extractions of the proteins using different solvents such as cold water, hot water, saline buffer pH 7 and sodium hydroxide was the best extractant. 6. The amino-acid content of the two seeds, whether raw or cooked, showed that they were deficient in methionine, cystine and tryptophan. Other essential amino acids were present in amounts higher than that given by the FAO provisional pattern. 7. Cooking the seeds by the popular methods used in the country resulted in an increase in the amounts of the amino acids, threonine, leucine and isoleucine, while the other amino acids present remained unchanged or decreased. It was also observed that cooking the seeds destroyed the trypsin inhibitors and haemagglutinins found in the two seeds.
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PMID:Phytochemical and nutritional studies on pigeon pea and kidney bean cultivated in Egypt. 96 10

We have used the fission yeast Schizosaccharomyces pombe to analyse the effects of in vitro mutagenesis of the four known phosphorylation sites in the chicken p34(cdc2) protein, Thr 14, Tyr 15, Thr 161 and Ser 277, upon cell cycle progression. We have studied both the effect of overexpression of mutant proteins in a cdc2+ background and assayed their ability to rescue null and temperature-sensitive alleles of cdc2. Mutations of Thr 14 and Tyr 15 within the ATP binding domain of p34(cdc2) that mimic constitutive phosphorylation cause dominant negative cell cycle arrest when overexpressed. In contrast, some substitutions that simulate permanent dephosphorylation of the corresponding sites advance dephosphorylation of the corresponding sites advance mitosis. These data confirm the model that p34(cdc2) function is negatively regulated by phosphorylation of residues in the ATP binding site. Mutagenesis of the conserved residue Thr 161 functionally inactivates p34(cdc2), and our data suggest that both phosphorylation and dephosphorylation events at Thr 161 are required for progression through the cell cycle. Mutations at the fourth site of phosphorylation. Ser 277, lead to cold-sensitive cell cycle arrest, in minimal but not rich growth medium, suggesting that this site is involved in monitoring the nutritional status of the cell.
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PMID:Vertebrate p34cdc2 phosphorylation site mutants: effects upon cell cycle progression in the fission yeast Schizosaccharomyces pombe. 150 Apr 41

The X-ray structures of two complexes of bovine ribonuclease-A produced by soaking pre-grown crystals in solutions of the inhibitors cytidylyl-2',5'-guanosine (2',5' CpG) and deoxycytidylyl-3',5'-guanosine (3',5'dCpdG) have been determined at 1.5 A resolution and refined by restrained least squares to R = 21.0% for 17,855 reflections, and R = 19.1% for 16,347 reflections, respectively. Binding of the substrate analogs to the protein has taken place in a completely unexpected and previously unreported manner. In each case the guanine base occupies the well characterized B1 pyrimidine binding site adjacent to Thr-45 (described by Richards, F.M., Wyckoff, H.W., Carlson, W.D., Allewell, N.M., Lee, B. and Mitsui, Y. (1971) Cold Spring Harbor Symp. Quant. Biol. 36, 35-54, and others including Palmer, R.A., Moss, D.S., Haneef, I. and Borkakoti, N. (1984) Biochim. Biophys. Acta 785, 81-88) having entered through a secondary channel external to the active site itself. We designate this reversed non-productive mode as retro-binding. In this mode of binding the SO4(2-) anion bound in the active site of the native protein crystals (Borkakoti, N., Moss, D.S. and Palmer, R.A. (1982) Acta Crystallogr. B38 2210-2217) has not been displaced by the phosphate of the inhibitor molecule as originally anticipated and observed in other studies. Instead the CMP or dCMP moiety of the inhibitor molecule is held loosely in a channel running towards the surface of the protein molecule and is thus completely external to the active site. Consequently, although it has been possible to model them, no attempt has been made to refine either the disordered cytosine in the CpG complex or the deoxycytosine in the dCpdG complex. The traditional B2 purine binding site of RNase (Richards et al., 1971) is unoccupied by the soaked inhibitors. Important changes that have taken place in the protein structure include: stabilization of both Lys-41 and Gln-11 via H-bonding to SO4(2-); stabilization of His-119 in the A conformation (Borkakoti, N., Moss, D.S. and Palmer, R.A. (1982) Acta Crystallogr. B38 2210-2217); and stabilization of SO4(2-) by H-bonds formed with the retro-bound guanine base. Binding of the inhibitors and stabilization of the active site is accompanied by displacement and redistribution of solvent molecules.
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PMID:Novel non-productively bound ribonuclease inhibitor complexes--high resolution X-ray refinement studies on the binding of RNase-A to cytidylyl-2',5'-guanosine (2',5'CpG) and deoxycytidylyl-3',5'-guanosine (3',5'dCpdG). 176 78

Our studies of the spatiotemporal availability of neurotrophic factors, coupled with tagged ligand binding assays that identify cell bearing receptors for these factors, should lead toward defining the physiological roles of these molecules in the animal. The use of the tagged ligands to identify factor-responsive cell lines has also provided new model systems for the examination of ligand-receptor interactions, as well as for the study of the subsequent induction of intracellular response pathways. To obtain insights into such intracellular pathways, we have molecularly cloned genes encoding a family of serine-threonine protein kinases, most closely related to kinases involved in the yeast response to pheromones. These kinases may be crucial regulators of early steps in the response of mammalian cells to neurotrophic factors as well as other extracellular signals.
Cold Spring Harb Symp Quant Biol 1990
PMID:Neurotrophic factors, their receptors, and the signal transduction pathways they activate. 196 66

The large subunit of RNA polymerase II contains a highly conserved and essential heptapeptide repeat (Pro-Thr-Ser-Pro-Ser-Tyr-Ser) at its carboxy terminus. Saccharomyces cerevisiae cells are inviable if their RNA polymerase II large subunit genes encode fewer than 10 complete heptapeptide repeats; if they encode 10 to 12 complete repeats cells are temperature-sensitive and cold-sensitive, but 13 or more complete repeats will allow wild-type growth at all temperatures. Cells containing C-terminal domains (CTDs) of 10 to 12 complete repeats are also inositol auxotrophs. The phenotypes associated with these CTD mutations are not a consequence of an instability of the large subunit; rather, they seem to reflect a functional deficiency of the mutant enzyme. We show here that partial deletion mutations in RNA polymerase II CTD affect the ability of the enzyme to respond to signals from upstream activating sequences in a subset of promoters in yeast. The number of heptapeptide repeats required for maximal response to signals from these sequences differs from one upstream activating sequence to another. One of the upstream elements that is sensitive to truncations of the CTD is the 17-base-pair site bound by the GAL4 transactivating factor.
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PMID:RNA polymerase II C-terminal repeat influences response to transcriptional enhancer signals. 221 64

Cholecystokinin (CCK) receptors were investigated in the tumoral acinar cell line AR 4-2 J derived from rat pancreas, after preincubation with 20 nM dexamethasone. At steady state binding at 37 degrees C (i.e., after a 5 min incubation), less than 10% of the radioactivity of [125I]BH-CCK-9 (3-(4-hydroxy-[125I]iodophenyl)propionyl (Thr34, Nle37) CCK(31-39)) could be washed away from intact cells with an ice-cold acidic medium, suggesting high and rapid internalization-sequestration of tracer. By contrast, more than 85% of the tracer dissociated rapidly after a similar acid wash from cell membranes prelabelled at steady state. In intact AR 4-2 J cells, internalization required neither energy nor the cytoskeleton framework. Tracer internalization was reversed partly but rapidly at 37 degrees C but slowly at 4 degrees C. In addition, two degradation pathways of the tracer were demonstrated, one intracellular and one extracellular. Intracellular degradation occurred at 37 degrees C but not at 20 degrees C and resulted in progressive intracellular accumulation of [125I]BH-Arg that corresponded, after 1 h at 37 degrees C, to 35% of the radioactivity specifically bound. This phenomenon was not inhibited by serine proteinase inhibitors and modestly only by monensin and chloroquine. Besides, tracer degradation at the external cell surface was still observable at 20 degrees C and yielded a peptide (probably [125I]BH-Arg-Asp-Tyr(SO3H)-Thr-Gly). This degradation pathway was partly inhibited by bacitracin and phosphoramidon while thiorphan, an inhibitor of endopeptidase EC 3.4.24.11, was without effect.
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PMID:Internalization-sequestration and degradation of cholecystokinin (CCK) in tumoral rat pancreatic AR 4-2 J cells. 226 8

Previously we reported that chymotryptic fragments of bovine adrenal 190-kDa microtubule-associated proteins (27-kDa fragment) and bovine brain tau (14-kDa fragment) contained microtubule-binding domain (Aizawa, H., Murofushi, H., Kotani, Hisanaga, S., Hirokawa, N., and Sakai, H. (1987) J. Biol. Chem. 262, 3782-3787; Aizawa, H., Kawasaki, H., Murofushi, H., Kotani, S., Suzuki, K., and Sakai, H. (1988) J. Biol. Chem. 263, 7703-7707). In order to study the structure of microtubule-binding domain of the two microtubule-associated proteins, we analyzed the amino acid sequence of the 27-kDa fragment and compared the sequence with that of the 14-kDa fragment. This revealed that 190-kDa microtubule-associated protein and tau contained at least one common sequence of 20 amino acid residues in their microtubule-binding domains. A synthetic polypeptide corresponding to the common sequence (Lys-Asn-Val-Arg-Ser-Lys-Val-Gly-Ser-Thr-Glu-Asn-Ile-Lys- His-Gln-Pro-Gly-Gly-Gly-Arg-Ala-Lys) was bound to microtubules competitively with the 190-kDa MAP. The apparent dissociation constant (KD) for the binding of the polypeptide to microtubules was estimated to be 1.8 x 10(-4) M, and the maximum binding reached 1.2 mol of the synthetic polypeptide/mol of tubulin dimer. This synthetic polypeptide increased the rate and extent of tubulin polymerization and decreased the critical concentration of tubulin for polymerization. The polypeptide-induced tubulin polymers were morphologically normal microtubules and were disassembled by cold treatment. The common sequence (termed assembly-promoting sequence) was thus identified as the active site of 190-kDa microtubule-associated protein and tau for the promotion of microtubule assembly. The reconstitution system of microtubules with this synthetic polypeptide with assembly-promoting sequence may be useful to elucidate detailed molecular mechanism of the promotion of microtubule assembly by microtubule-associated proteins.
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PMID:A common amino acid sequence in 190-kDa microtubule-associated protein and tau for the promotion of microtubule assembly. 249 69

The in vivo binding properties of cerebral mu and delta opioid receptors were investigated in mice after the intrastriatal injection of [3H][D-Ala2, MePhe4, Gly-ol5]enkephalin (DAGO) or [3H][D-Thr2,Leu5]enkephalyl-Thr (DTLET). Both peptides exhibited similar diffusion kinetics in the brain and 30-40% of [3H]DAGO or [3H]DTLET was shown to be present in the tissue 15 min after injection when maximal binding was observed. The specific binding of both agonists, defined as the fraction of the radioactivity bound to brain membranes which was displaced by 10 nmol of cold ligand, was reversible, saturable and displayed a pharmacological profile similar to that found in in vitro experiments. At doses producing a similar analgesic effect in the hot-plate test in mice, DTLET occupied 64% of delta sites and DAGO 15% of mu sites. However, because of the residual cross-reactivity of DTLET for mu sites, it appeared that both ligands occupied a similar number of mu receptors at their ED50 values, thus supporting a preferential involvement of mu opioid binding sites in the supraspinal pain control. [Met5]enkephalin inhibited the in vivo binding of both agonists only when the peptide was protected from degradation by the co-administration of a mixed inhibitor of enkephalin degrading enzymes RB38A (N[3(R)(hydroxyaminocarbonyl)-2-benzyl-1-oxopropyl]- L-phenylalanine). Unlike thiorphan, 5 nmol RB38A alone was able to inhibit [3H]DAGO binding by 60%. This result is the first direct demonstration of the existence of an in vivo tonic control of mu opioid receptor occupation by endogenous opioid peptides.
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PMID:Binding in vivo of selective mu and delta opioid receptor agonists: opioid receptor occupancy by endogenous enkephalins. 255 56

Regardless of the A, B, H, Le(a), Le(b), I and i activity, purified water-soluble blood group glycoproteins from human ovarian cyst fluid have a similar overall structure. They are polydisperse macromolecules (Mr 2.0 x 10(5) to several million) of similar composition (75 to 85% carbohydrate, 15 to 20% protein) and consist of multiple heterosaccharide side chains attached by an O-glycosidic linkage at their internal reducing ends to serine or threonine of the polypeptide backbone. About 90% of these carbohydrate side chains range in size from one to less than twenty-four sugar residues (twelve sugars in the internal structure and twelve key sugars specific as blood group determinants). Three-fourths of these side chains contain fewer than twelve sugars. A generalized blood group active carbohydrate chain is shown above. Three disaccharide units-Type I chain (Gal beta 1----3GlcNAc beta 1----3), Type II chain (Gal beta 1----4GlcNAc beta 1----6) and T determinant [Gal beta 1----3GalNAc alpha 1----Ser(Thr)]-are used to elucidate the internal structure of the carbohydrate chains. The complete internal structure is considered to have a core structure with four branches, to which the blood group key sugars are attached at the appropriate locations. The core structure is a tetrasaccharide, composed of one unit of Type I chain at the nonreducing end and the T determinant at the other end, linked to Ser or Thr of the protein moiety. Branch I is Type I chain and Branch II is Type II chain. They are linked to Gal at the nonreducing end of the core structure. Branch III is usually a Type II chain, but may sometimes be a Type I chain, linked to the GalNAc of the reducing end. The length of Branch III can be increased by adding one or more monosaccharides of Type I chain sequence such as Gal beta 1----3GlcNAc beta 1----3Gal beta 1----4GlcNAc beta 1----6GalNAc alpha 1----Ser(Thr), a combination of Type I and Type II chains. A new Branch IV is made up of Type II chain, which in turn is linked to the Gal end of the T determinant. The Type II chains react with the antibody to the type XIV pneumococcal capsular polysaccharide and with the anti-I(Ma) cold agglutinin.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Structural concepts of the human blood group A, B, H, Le(a), Le(b), I and i active glycoproteins purified from human ovarian cyst fluid. 305 18

The transport of glycine and L-lysine into murine P388 leukemia cells has been examined. Glycine transport appears to be shared by both systems A and ASC in P388 cells. Glycine transport is Na+-dependent and is effectively blocked by alpha-(methylamino)isobutyric acid, threonine and alanine but only a marginal reduction in transport is seen with 100-fold excess cold 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid. System gly is not expressed in P388 cells. Lysine is largely transported by a Na+-independent, pH-insensitive system with a Km of 0.079 mM. Lysine transport is relatively unaffected by the addition of 100-fold excess cold alpha-(methylamino)isobutyric acid, 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid and the anionic amino acids, L-glutamate and L-aspartate. A partial inhibition of lysine transport was observed with L-threonine and L-leucine while L-arginine and L-histidine radically decreased lysine transport. Lysine appears to be transported by a system similar to the system y+ seen in cultured human fibroblasts, Ehrlich ascites cells, and hepatoma cell lines.
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PMID:Further studies on amino acid transport in murine P388 leukemia cells in vitro. Presence of system y+. 310 85


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