Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00492 (hypoxanthine-guanine phosphoribosyltransferase)
 2,385 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A patient with clearly developed features of the full Lesch-Nyhan syndrome and complete lack of activity of hypoxynthine-phosphoribosyltransferase is described. The clinical picture was characterized by absence of spasticity, good control of autoaggression by behavior therapy, and no signs of renal insufficiency. After death, which was caused by a viral infection, pathological examination and a search for material immunologically cross-reacting with hypoxanthine-phosphoribosyltransferase were possible. In spite of increased serum urate levels and raised urinary uric acid excretion there were no signs of urate deposits or damage in the internal organs, including the kidneys. Crossreactive material was found in the liver, kidneys and spleen, a relatively rare finding in the full Lesch-Nyhan-syndrome. The absence of any specific pathological changes in the brain of this patient is in agreement with earlier reports.
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PMID:Pathological and immunological observations in a case of Lesch-Nyhan-syndrome. 49 64

The purine phosphoribosyltransferases of Crithidia fasciculata were identified and some of their properties described. The organism possesses three separate enzymes for the production of AMP, IMP, and GMP. The evidence for this comes from the observed differences in elution patterns from gel filtration columns, differences in heat sensitivity, and especially the clear separation of hypoxanthine phosphoribosyltransferase from guanine phosphoribosyltransferase by affinity chromatography on GMP-agarose. APRTase is activated most efficiently by Zn++, whereas HPRTase and GPRTase are activated most effectively by Co++. In no case did the product mononucleotides produce strong inhibition of the transferase activities.
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PMID:The purine phosphoribosyltransferases of Crithidia fasciculata. 51 49

The results are described of a behavioural programme designed to modify self-injurious behaviour of a child with Lesch-Nyhan syndrome. The treatment combined extinction of the injurious behaviour and reinforcement of alternative behaviour, and was successful in the controlled hospital environment. However, an attempt to teach the parents to continue the treatment at home failed. The results are discussed in terms of the possible relationship between organic and environmental factors in maintaining the injurious behaviour, and the importance of analysing both the behaviour itself and the factors (including familial) maintaining it. It is suggested that parents should be advised about management of behavioural problems at an early age.
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PMID:Problems in the behavioural treatment of self-injury in the Lesch-Nyhan syndrome. 52 Jul 17

Chinese hamster ovary cells were treated with the DNA-crosslinking chemicals, mitomycin C (MMC) and porfiromycin (POR), and their monofunctional derivative decarbamoyl mitomycin C (DCMMC). After exposure, the cells were studied for the induction of sister-chromatid exchanges (SCEs) and mutations at the hypoxanthine phosphoribosyltransferase and adenine phosphoribosyltransferase loci. The frequency of SCEs varied significantly in successive sampling intervals, requiring the weighting of each interval by the percentage of second-division mitosis in that interval to obtain the mean SCE frequency for each dose. All 3 compounds were potent inducers of SCEs but weakly mutagenic. All 3 chemicals by concentration were approximately equally effective in inducing SCEs or mutations. When the induced SCEs and mutations were compared at equal levels of survival, DCMMC was slightly more effective than MMC or POR in inducing SCEs and somewhat less mutagenic. These results indicate that the DNA interstrand crosslink is not the major lesion responsible for the induction of SCE or mutation by these compounds.
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PMID:DNA crosslinking, sister-chromatid exchange and specific-locus mutations. 52 65

The patient, H.Chr.B., was among the first reported with hyperuricemia and central nervous system symptoms. He has been found to have a variant of hypoxanthine guanine phosphoribosyl transferase (HPRT; E.C.2.4.2.8) distinct from the enzyme present in patients with the Lesch-Nyhan syndrome. The patient had chroeoathetosis, spasticity, dysarthric speech, and hyperuricemia. However, his intelligence was normal and he had no evidence of self-mutilation. There was no activity of HPRT in the lysates of erythrocytes and cultured fibroblasts when analyzed in the usual manner. Using a newly developed method for the study of purine metabolism in intact cultured cells, this patient was found to metabolize some 9% of 8-14C-hypoxanthine, and 90% of the isotope utilized was converted to adenine and guanine nucleotides. In contrast, cells from patients with the Lesch-Nyhan syndrome were virtually completely unable to convert hypoxanthine to nucleotides. The patient's fibroblasts were even more efficient in the metabolism of 8-14C-guanine, which was utilized to the extent of 27%, over 80% of which was converted to guanine and adenine nucleotides. The growth of the cultured fibroblasts of this patient was intermediate in media containing hypoxanthine aminopterin thymidine (HAT), whereas the growth of Lesch-Nyhan cells was inhibited and normal cells grew normally. Similarly in 8-azaguanine, 6-thioguanine, and 8-azahypoxanthine, the growth of the patient's cells was intermediate between normal and Lesch-Nyhan cells. These observations provide further evidence for genetic heterogeneity among patients with disorders in purine metabolism involving the HPRT gene. They document that this famous patient did not have the Lesch-Nyhan syndrome.
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PMID:Utilization of purines by an HPRT variant in an intelligent, nonmutilative patient with features of the Lesch-Nyhan syndrome. 52 96

Total and specific activity of the enzyme hypoxanthine phosphoribosyltransferase (HPRT) varied widely among six tissues from C3H/f mice; the highest levels of activity were in brain. More striking were thermostability differences in tissue enzymes. Although brain, spleen, and kidney HPRT retained 65% basal activity after 15 min at 85 C, heart, liver, and erythrocyte HPRT retained only 20-30% initial activity. Kidney HPRT behaved as monospecific heat-stable enzyme (K-denatauration=0.022/min, and liver enzyme behaved as monospecific heat-labile enzyme (K-denaturation=0.061/min), while other tissues appeared to contain both forms of the enzyme. Multiple electrophoretic activity bands were present in all tissues; no activity band was restricted to a single tissue. The data presented here are consistent with the hypothesis that the distinct tissue properties of HPRT result from posttranslational modification of the product of a single genetic locus which is expressed in all tissues.
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PMID:Developmental expression of murine HPRT. I. Activities, heat stabilities, and electrophoretic mobilities in adult tissues. 54 17

A locus on chromosome 7 controls the electrophoretic mobility of hypoxanthine phosphoribosyltransferase (HPRT) isoenzymes in mouse erythrocytes, but not in several other tissues. This locus is designated Hma (HPRT mobility alteration) and maps very close to the Hbb locus. The A/J, AKR/J, AU/SsJ, BALB/cJ, CBA/J, C3H/HeJ, DBA/2J, LP/J, RF/J, SEA/Gn, ST/BJ, and 129/J strains and our population of Swiss albino mice have the Hmaa allele. Hmaa is dominant to Hmab, which is found in the C57BL/6J, C57BL/KsJ, C58/J, LT/Sv, MA/MyJ, SJL/J, and SWR/J strains. Both alleles are found in feral Mus musculus. In our conditions, homozygotes for Hmab have two major bands of HPRT activity after electrophoresis of extracts of erythrocytes and of other tissues. Heterozygotes and Hmaa homozygotes have three bands in erythrocyte extracts but two band in other tissues.
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PMID:Isoenzyme pattern of HPRT in murine erythrocytes: control by an autosomal locus. 54 25

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) activity was measured in red cells and in skeletal muscles of normal and Duchenne subjects. [8-14C] hypoxanthine was used as substrate, and 5-phospho-alpha-D-ribose 1-diphosphate (PRPP) was used as the ribose-5-phosphate donor. The [8-14C] inosine monophosphate (IMP) formed was separated by high-voltage electrophoresis, and radioactivity was measured by lipid scintillation counting. HGPRT activity in Duchenne and normal red-cell hemolysates was similar, but such activity was significantly higher in Duchenne than in normal muscle homogenates. Red cells of both normal and Duchenne subjects had significantly higher enzyme activity than did skeletal muscles. It is suggested that increased HGPRT activity may be involved in enhancing protein synthesis by increasing intracellular levels of purine ribonucleotides.
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PMID:Hypoxanthine-guanine phosphoribosyltransferase activity of blood and muscle in Duchenne dystrophy. 54 41

The synthesis, characterization, and biochemical evaluation of 1-beta-D-ribofuranosylnaphtho[2,3-d]imidazole-4,9-dione (3), 2-beta-D-ribofuranosylnaphtho[2,3-d]pyrazole-4,9-dione (6), and 2-beta-D-ribofuranosylnaphthol[2,3-d]triazole-4,9-dione (9) are reported. These quinone nucleosides and the corresponding quinone heterocycles were tested as inhibitors of purine nucleotide biosynthesis in Ehrlich ascites cells. The nucleosides 3 and 9 and naphtho[2,3-d]imidazole-4,9-dione were effective inhibitors of hypoxanthine phosphoribosyltransferase.
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PMID:Synthesis and biochemical evaluation of nucleosides of naphthoquinone heterocycles. 55 66

Experiments are described leading to partial compensation of a deficiency in the enzyme hypoxanthine-guanine phosphoribosyltransferase in mutant cells by supplying the cells with exogenous purified enzymes. DEAE-dextran is an effective helper agent, whereas poly (L-lysine), lysolecithin and amphotericin B seem to inhibit the entry of the enzymes of their activity. Enzyme preparation from Chinese hamster was found to have different effects in different mutant cell lines. In mutant Chinese hamster cells, the electrophoretic activity pattern remains unchanged for the Chinese hamster enzyme, but changes progressively to faster-moving activity peaks for the human enzyme after several hours. The metabolic effect of the incorporated enzyme is in the range between 3 and 4% of the normal cellular enzyme activity which corresponds to a 10--20 fold increase of hypoxanthine-guanine phosphoribosyltransferase activity in the mutant cells.
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PMID:The incorporation of homologous and heterologous hypoxanthine-guanine phosphoriboxyltransferase into mutant cells. 56 35


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