Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.8.1.4 (diaphorase)
 2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Various regulators of protein kinase activities were tested for their effects on the in vitro transfer of phosphate from [gamma-32P]ATP to four proteins of rat brain synaptic particulate preparations. One protein, of apparent molecular weight 44,000, accepted 32P in the presence of 8 mM EDTA and no added Mg2+. It was the major phosphoprotein of brain mitochondria. Its phosphorylation was inhibited by pyruvate and stimulated by K+, and it comigrated in electrophoretic gels with authentic alpha-subunit of pyruvate: lipoamide oxidoreductase (decarboxylating) (EC 1.2.4.1) from bovine heart. The major kinase acting on three proteins of apparent molecular weights 24,000, 21,000, and 19,000 was stimulated by Ca2+, by preincubation with phospholipase C, and by 12-tetradecanoyl 4-beta-phorbol 13-acetate. Phosphorylation of these lower-molecular-weight proteins was inhibited by ACTH1-24, by cyclic 3',5'-adenosine monophosphate, and by 50 microM trifluoperazine. The stimulatory effect of Ca2+ was antagonized by calmodulin. The kinase in question appears to be B-50 protein kinase or protein kinase C.
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PMID:Regulation of phosphate incorporation into four brain phosphoproteins that are affected by experience. 298 Dec 89

Hodological, electrophysiological, and ablation studies indicate a role for the basal forebrain in telencephalic vocal control; however, to date the organization of the basal forebrain has not been extensively studied in any nonmammal or nonhuman vocal learning species. To this end the chemical anatomy of the avian basal forebrain was investigated in a vocal learning parrot, the budgerigar (Melopsittacus undulatus). Immunological and histological stains, including choline acetyltransferase, acetylcholinesterase, tyrosine hydroxylase, dopamine and cAMP-regulated phosphoprotein (DARPP)-32, the calcium binding proteins calbindin D-28k and parvalbumin, calcitonin gene-related peptide, iron, substance P, methionine enkephalin, nicotinamide adenine dinucleotide phosphotase diaphorase, and arginine vasotocin were used in the present study. We conclude that the ventral paleostriatum (cf. Kitt and Brauth [1981] Neuroscience 6:1551-1566) and adjacent archistriatal regions can be subdivided into several distinct subareas that are chemically comparable to mammalian basal forebrain structures. The nucleus accumbens is histochemically separable into core and shell regions. The nucleus taeniae (TN) is theorized to be homologous to the medial amygdaloid nucleus. The archistriatum pars ventrolateralis (Avl; comparable to the pigeon archistriatum pars dorsalis) is theorized to be a possible homologue of the central amygdaloid nucleus. The TN and Avl are histochemically continuous with the medial aspects of the bed nucleus of the stria terminalis and the ventromedial striatum, forming an avian analogue of the extended amygdala. The apparent counterpart in budgerigars of the mammalian nucleus basalis of Meynert consists of a field of cholinergic neurons spanning the basal forebrain. The budgerigar septal region is theorized to be homologous as a field to the mammalian septum. Our results are discussed with regard to both the evolution of the basal forebrain and its role in vocal learning processes.
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PMID:Organization of the avian basal forebrain: chemical anatomy in the parrot (Melopsittacus undulatus). 1245 5

Capacitation is a process that confers fertilizing ability to spermatozoa and this critical event occurs in the development of mammalian spermatozoa during their transit through the female reproductive tract and precedes fertilization. Because spermatozoa are relatively silent in transcription and translation, posttranslational modifications perform the regulatory functions in these cells during capacitation. In this report, we identify a candidate protein, dihydrolipoamide dehydrogenase, which is a post-pyruvate metabolic enzyme, exhibiting tyrosine phosphorylation during hamster spermatozoal capacitation. This is the first report showing dihydrolipoamide dehydrogenase as a phosphoprotein. The cDNA sequence of hamster testes dihydrolipoamide dehydrogenase does not show any variation from the already reported mammalian dihydrolipoamide dehydrogenases. Downregulation of the activity of the hamster spermatozoal enzyme by its specific inhibitor, 5-methoxyindole-2-carboxylic acid, blocks acrosome reaction completely and hyperactivation partially, confirming the role of dihydrolipoamide dehydrogenase in hamster spermatozoal capacitation. We also delineate the temporal involvement of glucose and pyruvate-lactate, showing that the former is required in the earlier stages and the latter for the later stages of hamster spermatozoal capacitation. The essentiality of pyruvate-lactate during hyperactivation and acrosome reaction necessitates the involvement of the post-pyruvate-lactate enzyme, dihydrolipoamide dehydrogenase.
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PMID:Novel tyrosine-phosphorylated post-pyruvate metabolic enzyme, dihydrolipoamide dehydrogenase, involved in capacitation of hamster spermatozoa. 1464 6

Neutrophils generate microbicidal oxidants through activation of a multicomponent enzyme called NADPH oxidase. During activation, the cytosolic NADPH oxidase components (p47(phox), p67(phox), p40(phox), and Rac2) translocate to the membranes, where they associate with flavocytochrome b(558), which is composed of gp91(phox)/NOX2 and p22(phox), to form the active system. During neutrophil stimulation, p47(phox), p67(phox), p40(phox), and p22(phox) are phosphorylated; however, the phosphorylation of gp91(phox)/NOX2 and its potential role have not been defined. In this study, we show that gp91(phox) is phosphorylated in stimulated neutrophils. The gp91(phox) phosphoprotein is absent in neutrophils from chronic granulomatous disease patients deficient in gp91(phox), which confirms that this phosphoprotein is gp91(phox). The protein kinase C inhibitor GF109203X inhibited phorbol 12-myristate 13-acetate-induced phosphorylation of gp91(phox), and protein kinase C (PKC) phosphorylated the recombinant gp91(phox)- cytosolic carboxy-terminal flavoprotein domain. Two-dimensional tryptic peptide mapping analysis showed that PKC phosphorylated the gp91(phox)-cytosolic tail on the same peptides that were phosphorylated on gp91(phox) in intact cells. In addition, PKC phosphorylation increased diaphorase activity of the gp91(phox) flavoprotein cytosolic domain and its binding to Rac2, p67(phox), and p47(phox). These results demonstrate that gp91(phox) is phosphorylated in human neutrophils by PKC to enhance its catalytic activity and assembly of the complex. Phosphorylation of gp91(phox)/NOX2 is a novel mechanism of NADPH oxidase regulation.
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PMID:Regulation of the phagocyte NADPH oxidase activity: phosphorylation of gp91phox/NOX2 by protein kinase C enhances its diaphorase activity and binding to Rac2, p67phox, and p47phox. 1902 40