Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039483 (giant cell arteritis)
 3,204 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The J-variant of human serum butyrylcholinesterase (BChE) causes both an approximately two-thirds reduction of circulating enzyme molecules and a corresponding decrease in the level of BChE activity present in serum. Since the level of serum BChE activity and the duration of succinylcholine apnea are inversely correlated, this marked decrease in activity makes individuals with the J-variant more susceptible than usual subjects to prolonged apnea from succinylcholine. We reinvestigated the same family in which Garry et al. identified the J-variant phenotype. The atypical, fluoride, and K-variant mutations were also identified in members of the 47-person pedigree. DNA amplification by PCR, followed by direct sequencing of the amplified DNA, led to the finding that the J-variant phenotype of human serum BChE was associated with two DNA point mutations in the coding region. One of these was the mutation previously identified with the K-variant phenotype (GCA----ACA; Ala539----Thr). The other was an adenine-to-thymine transversion at nucleotide 1490, which changed amino acid 497 from glutamic acid to valine (GAA----GTA; Glu497----Val). This latter point mutation was named the J-variant mutation (formal name BCHE*497V). The J-variant mutation has not been identified without the K-variant mutation. The J-variant mutation created an RsaI-enzyme RFLP. Two additional point mutations, located in the noncoding regions of the gene, were also found to be linked with the J-variant and K-variant point mutations on the same allele. These noncoding polymorphic mutations had previously been found linked to the atypical and K-variant point mutations. A summary table shows dibucaine, fluoride, and Hoffmann-La Roche compound Ro 2-0683 inhibition numbers for 119 samples whose DNA has been sequenced. Eighteen BChE genotypes are represented.
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PMID:DNA mutations associated with the human butyrylcholinesterase J-variant. 134 96

DNA structural changes induced by bleomycin have been investigated using diethylpyrocarbonate and permanganate as probes under conditions in which the antibiotic binds to, but does not cut the DNA. Diethyl-pyrocarbonate shows an enhanced reaction with adenines in the presence of the antibiotic in the sequences GTA greater than GCA greater than GAA, on the 3' side of the drug cutting site (GPy). Permanganate ions display an enhanced reactivity at the second pyrimidine of the sequence GPyPy. The results are consistent with a model in which bleomycin distorts the structure of the base pair on the 3' side of its binding site.
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PMID:Diethylpyrocarbonate and permanganate provide evidence for an unusual DNA conformation induced by binding of the antitumour antibiotics bleomycin and phleomycin. 245 9

The nucleotide sequences of the recessive dnaQ49 and the dominant mutD5 mutator were determined. The dnaQ49 mutator has a single base substitution in the dnaQ gene, thus causing one amino acid change, 96Val (GTG)----Gly (GGG), in the DnaQ protein (epsilon subunit of DNA polymerase III holoenzyme). The mutD5 mutator possesses two base substitutions in the same gene, resulting in two amino acid changes, 73Leu (TTG)----Trp (TGG) and 164Ala (GCA)----Val (GTA), which were designated the mutD52 and mutD51 mutations, respectively. Construction of chimaeric genes carrying one or two of these mutations revealed: either mutD51 or mutD52 alone causes the dominant mutator phenotype when present in a multi-copy plasmid; mutator phenotype when present in a low-copy plasmid; the dominant mutD51 mutator activity is suppressed by the dnaQ49 mutation when both mutations are present in the same gene. Based on these findings, we devised a model for the action of these mutators.
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PMID:Structure and function of dnaQ and mutD mutators of Escherichia coli. 354 May 31

The ancestral gene for immunoglobulin light-chain variable regions (Ig VLs) of the kappa as well as the lambda class apparently arose from about 12 tandem repeats of the 48-base-long primordial building block sequence TCT-TGC-GCA-GTA-AGT-CCA-CTC-CAG-GTC-ATA-TCC-AGT-CAG-GCT-GCT-GAA. Even today, amino acid residues 67 to 82 of each Ig V kappa L are still specified by a direct descendant in toto of the above-noted primordial building block, whereas amino acid residues 14 to 25 are invariably specified by its truncated copy. The Ig VL primordial building block presently identified is 100% complementary to the Ig VH (heavy-chain variable region) primordial building block previously identified. In the recognition of specific antigenic determinants by antibodies, Ig VL and Ig VH of light-chain--heavy-chain dimers have to complement each other. It is perhaps fitting that the primordial building blocks of the two are represented by the complementary strands of the same 48-base-pair-long DNA sequence.
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PMID:The 48-base-long primordial building block of immunoglobulin light-chain variable regions is complementary to the primordial building block of heavy-chain variable regions. 680 18

Footprinting with methidiumpropyl-EDTA.FeII has been used to map the binding sites on duplex DNA of two closely related benzopyridoindole derivatives which selectively stabilize triple-helical DNA-oligonucleotide complexes. Both ligands bind to many sites, including certain oligopurine.oligopyrimidine tracts, with a weak preference for some (but not all) sequences rich in A.T base pairs. This indifference to primary sequence, with evidence of binding to the commonly disfavoured (A)n.(T)ntracts, may at least partially explain why the ligands stabilize triplex structures composed of T.A.T pairings. Neither 3-methoxy-7H-8-methyl-11- [(3'amino)propylamino]benzo[e]pyrido[4, 3-b]indole (BePI) nor 3- methoxy-7-[3'-diethylamino)propylamino]-10-methyl-11H- benzo[g]pyrido[4,3-b]indole (BgPI) affect the reaction of dimethyl sulphate or potassium tetrachloropalladinate with the N7 of purines in the major groove, but both enhance the reactivity of purines (mostly adenine residues) towards diethylpyrocarbonate, both proximal and distal to their identified binding sites. With potassium permanganate and osmium tetroxide/pyridine, probes for the accessibility of the 5,6 double bond of pyrimidine residues, BgPI has a more potent effect than BePI and, generally, the reaction with KMnO4 is more pronounced than that with OsO4. BgPI conspicuously potentiates the oxidation of pyrimidines in the triplet sequences 3'-ATA, 3'-GTA and 3'-GCA, whereas BePI enhances the reactivity of OsO4 towards thymine in sequences 3'-ATYR, with no effect on cytosine residues. Thus, despite their structural homology and common lack of specific sequence preferences, the two benzopyridoindole derivatives induce distinct conformational changes in duplex DNA, not just within the sites where footprints can be detected.
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PMID:Localized chemical reactivity in double-stranded DNA associated with the intercalative binding of benzo[e]pyridoindole and benzo[g]pyridoindole triple-helix-stabilizing ligands. 755 72

In the present study we investigated the frequency of p16 gene exon 2 mutations in 35 malignant gliomas, using either direct sequencing of the PCR products or cloning into the pCRII vector and sequencing of the cloned PCR products. No mutations were detected during direct sequencing of the PCR products. However, after sequencing of individual clones, we found multiple mutations in 5 tumors involving codons 73(GCC to ACC, Ala to Thr), 76 (GCC to GTC, Ala to Val), 85(GCT to ACT, Ala to Thr), 98(CAC to TAC, His to Tyr), 102 (GCG to GTG, Ala to Val), 106 (GTG to ATG, Val to Met), 107 (CGC to TGC, Arg to Cys), 127 (GCA to GTA, Ala to Val), 128 (CGG to TGG, Arg to Trp) and 136 (GGC to GAC, Gly to Asp). Mutations were found only in glioblastomas and were either C to T or G to A transitions. Each mutation was detected in a small percentage of tumor cells (1.3-22%) using individual colony sequencing and southern hybridization with mutant oligonucleotides, consistent with the heterogenous cell population of glioblastomas. The presence of p16 gene mutations only in glioblastomas suggests that they are late events in glioma development.
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PMID:Mutations of the p16 gene in gliomas. 855

A new maximal circular code X0(MIT) with two permutated maximal circular codes X1(MIT) and X2(MIT) is identified in the protein coding genes of mitochondria. The three subsets of 20 trinucleotides X0(MIT)={ACA, ACC, ATA, ATC, CTA, CTC, GAA, GAC, GAT, GCA, GCC, GCT, GGA, GGC, GGT, GTA, GTC, GTT, TTA, TTC}, X1(MIT) and X2(MIT) are in frame 0 (reading frame), 1 and 2 respectively. X1(MIT) and X2(MIT) are deduced by one and two circular permutations of X0(MIT) respectively. The code X0(MIT) has four important properties: a length of the minimal window to automatically retrieve frame 0 which is equal to five nucleotides; an occurrence probability equal to 6.3 x 10(-5); a low frequency (12% in average) of misplaced trinucleotides in the shifted frames; and an occurrence of four types of nucleotides in the first and second trinucleotide sites but no nucleotide G in the third trinucleotide site. Several biological consequences are presented in the Discussion.
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PMID:A circular code in the protein coding genes of mitochondria. 944 20

Germline mutations in the RET proto-oncogene have been shown to be the underlying cause of multiple endocrine neoplasia type 2 (MEN 2A and 2B) and familial medullary thyroid carcinoma (FMTC). Some cases of sporadic medullary thyroid carcinoma (sporadic MTC) are reported to have specific codon 918, 883 and 768 mutations of the RET gene in tumor tissues. We examined RET gene mutations in 40 Japanese cases who had previously undergone surgery for sporadic MTC. DNA extracted from formalin-fixed tumor tissues and corresponding normal thyroid tissues or peripheral blood leukocytes was analyzed for mutations of exon 10, 11, 13, 14 and 16 of the RET gene by DNA sequencing and by mutation-specific restriction enzyme analysis. Germline RET point mutations were found in six of 40 cases (15%), cysteine residues at codon 618 in two, codon 634 in three and valine residue at codon 804 in one, and were newly identified as heritable MTC. Of the remaining 34 sporadic MTC cases, four (12%) had tumor-specific RET point mutations. Two were found in exon 16; one case showed an ATG to ACG (Met to Thr) mutation at codon 918, and the other showed two point mutations, ATG to ACG (Met to Thr) at codon 918 and GCA to GTA (Ala to Val) at codon 919 with loss of the wild-type allele, suggesting that both alleles at the RET locus were altered. The other two were found in exon 13; one case showed a CCG to TCG (Pro to Ser) mutation at codon 766 and the other showed a silent mutation, GTC to GTT (Val) at codon 778 with loss of the wild-type allele. There was no association of sporadic mutations with recurrence or prognosis in patients with sporadic MTC. The low rate of somatic RET mutation at codon 918 in our sporadic MTC suggests that as yet unknown factors may be involved. Genetic alterations in both alleles may have an important role in small fraction of sporadic MTCs.
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PMID:Novel point mutations and allele loss at the RET locus in sporadic medullary thyroid carcinomas. 961 47

A point mutation which caused a silent phenotype of human serum butyrylcholinesterase (BChE) was identified in the DNA of a 47-year-old Japanese woman who visited our hospital complaining of hypertension. The propositus exhibited an unusually low level of BChE activity, whereas her younger sister and her daughter had intermediate levels of BChE activity and her elder sister a normal level. Immunologically, the amount of BChE protein in the serum of the propositus was normal. DNA sequence analysis of the propositus identified a point mutation at codon 199 (GCA --> GTA), resulting in a Ala --> Val substitution. This alteration is one downstream codon from the catalytic active site (Ser, 198). A family study showed her younger sister and her daughter to have the same mutation.
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PMID:Identification of a point mutation associated with a silent phenotype of human serum butyrylcholinesterase--a case of familial cholinesterasemia. 969 84

Mxi1 is thought to negatively regulate Myc function and may therefore be a potential tumor suppressor gene. Little effort has yet been made to find alterations involving this gene in human solid tumors. We screened 31 human gastric cancers, 7 esophageal cancers, 85 bone and soft tissue tumors of various types, including 4 neurofibrosarcomas. We also examined 29 human tumor cell lines consisting of 12 esophageal cancers, 7 glioma/glioblastomas and 10 others for Mxi1 mutations in exons 1, 2, 4 (HLH domain), 5 and 6. Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and subsequent sequencing revealed three distinct polymorphisms in the intron-exon boundary upstream from exon 6. We discovered a missense mutation, GCA to GTA (Ala 54 Val), in exon 2 in a neurofibrosarcoma patient (case 1), two missense mutations, AAA to CAA (Lys 118 Gln) and GAA to GGA (Glu 154 Gly) in exon 5 of another neurofibrosarcoma patient (case 2), and 3 amino acid substitutions, GTG to GCG (Val 179 Ala), GTT to GCT (Val 181 Ala) and TTC to CTC (Phe 186 Leu), in a third neurofibrosarcoma patient (case 3). In case 3, loss of heterozygosity was also demonstrated by informative (TTC)3/(TTC)2 polymorphism. Our data demonstrate that mutations occur in the Mxi1 gene in neurofibrosarcoma. Missense mutations in the functional domain of Mxi1 in these cases may be involved in the pathogenesis of neurofibrosarcoma.
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PMID:Mxi1 mutations in human neurofibrosarcomas. 1047 Feb 86


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