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

Genomic DNA from two families exhibiting the K-variant phenotype of serum butyrylcholinesterase was amplified by PCR and sequenced to determine the molecular basis of this variant. The K-variant phenotype was found to be associated with a DNA transition from guanine to adenine at nucleotide 1615, which caused an amino acid change from alanine 539 to threonine (GCA----ACA; Ala539----Thr). There was a 30% reduction of serum butyrylcholinesterase activity associated with this mutation. Amplification and sequencing of DNA from a random sample of 47 unrelated people gave a frequency of .128 for the K-variant allele. Thus, 1 person in 63 should be homozygous for the K-variant, making the K-variant the most common butyrylcholinesterase variant. The K-variant mutation was also found to be present in 17 (89%) of 19 butyrylcholinesterase genes containing the point mutation which causes the atypical phenotype of butyrylcholinesterase (GAT----GGT; Asp70----Gly). The presence of the K-variant in the same molecule as the atypical variant does not contribute to the qualitative change in the atypical enzyme, but it most likely accounts for the approximately one-third reduction in Vmax of butyrylcholinesterase activity in atypical serum. Two additional point mutations located in noncoding regions of the gene were also observed to be in linkage disequilibrium with the K-variant mutation. As many as four different point mutations have been identified within a single butyrylcholinesterase gene. Inhibition tests of the enzyme in plasma are usually used to distinguish the K-variant from the usual enzyme when the former is present with the heterozygous atypical variant (AK phenotype vs. UA phenotype). Inhibition tests were performed on plasma enzyme from the four possible genotypic combinations of the heterozygous atypical mutation with or without the K-variant mutation on either allele; we found that the AK phenotype was caused by three genotypes (A/K, AK/K, and U/A) and that the UA phenotype was caused by two genotypes (U/A and U/AK).
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PMID:DNA mutation associated with the human butyrylcholinesterase K-variant and its linkage to the atypical variant mutation and other polymorphic sites. 157 Aug 38

A female with recurrent thrombosis was found to have a functional abnormality of antithrombin, with a ratio of functional to immunological activity in plasma of approximately 50%. Crossed immunoelectrophoresis in the presence of heparin was normal, indicating an abnormality of the reactive site, rather than the heparin binding domain. Accordingly, the antithrombin was isolated by heparin-Sepharose chromatography: this produced a mixture of normal and variant antithrombin, as the patient was heterozygous for the abnormality. To remove the normal component, the antithrombin was passed through a column of thrombin-Sepharose. On sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), prior to its application to thrombin-Sepharose, the antithrombin migrated as a single band with identical mobility to that of normal antithrombin. After thrombin-Sepharose, the purified variant component was proteolysed, and migrated as two components, one with a reduced and one with enhanced mobility under non-reducing conditions. This demonstrated that the variant was unable to form stable inhibitor-thrombin complexes and was cleaved in a substrate reaction with thrombin. One site of cleavage was unambiguously ascertained to be the Arg 393-Ser 394 reactive site bond, by NH2 terminal sequencing of the cleaved variant antithrombin: 10 steps beginning at the P1' position, Ser-Leu-Asn-Pro-Asn-Arg,..., were clearly identified. The mutation responsible for this defect was studied by polymerase chain reaction (PCR) amplification of exon 6 of the antithrombin gene and direct sequencing of the amplified product. The presence of both a G and A in the first position of codon 382, identified the mutation GCA to ACA, which results in the substitution of Ala 382 to Thr. This is identical to that reported for antithrombin Hamilton (Devraj-Kizuk et al, 1988), although antithrombin gene polymorphism analysis suggests that the antithrombin Glasgow II mutation has arisen independently. We have recently shown (Caso et al, 1991) that mutation at a nearby position, Ala 384 to Pro, also transforms another variant, antithrombin Vicenza/Charleville, into a substrate for thrombin. The present results with antithrombin Glasgow II suggest that all the alanine residues at the base of the reactive site loop in positions P12-10 may be important for the formation of a stabilized inhibitor-thrombin complex.
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PMID:Antithrombin Glasgow II: alanine 382 to threonine mutation in the serpin P12 position, resulting in a substrate reaction with thrombin. 191 89

In this report, point mutations of the K-ras gene at codon 146 were analyzed in 25 cases of colon cancer, 4 cases of lung cancer, and 41 cases of lymphoid malignancy. A codon 146 mutation substituting threonine (ACA) for alanine (GCA) was detected in the tumor tissue of a patient with colon cancer and was not detected in the normal tissue of the same patient. Any additional mutations of the ras gene family were not detected in this patient. These results suggest that the codon 146 mutation of the K-ras gene could be involved in the development of naturally occurring human malignancies.
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PMID:A novel point mutation at codon 146 of the K-ras gene in a human colorectal cancer identified by the polymerase chain reaction. 201 78

Our laboratory has recently shown that several variant forms of human butyrylcholinesterase, associated with unusual sensitivity to succinylcholine, are caused by specific mutations within the structural DNA coding for this enzyme. Atypical (dibucaine-resistant) butyrylcholinesterase is caused by a point mutation at nucleotide position 209(GAT-- greater than GGT), which changes aspartate 70 to glycine. One fluoride-resistant variant family has a point mutation at nucleotide 728(ACG-- greater than ATG), which changes threonine 243 to methionine. Another type of fluoride-resistant variant has a point mutation at nucleotide 1169(GGT-- greater than GTT), which changes glycine 390 to valine. One type of silent phenotype is due to a frame-shift mutation at nucleotide position 351(GGT-- greater than GGAG). A polymorphic site at nucleotide position 1615 (GCA/ACA), coding for Ala/Thr, accounts for the quantitative K-variant, which causes an approximate one-third reduction of activity, if Thr occupies that position at codon 539. Examples are given to illustrate the advantages of using a combination of the new DNA analytical techniques, including: the use of allele-specific probes, with the standard serum cholinesterase phenotyping methods. More accurate typing of patients with certain variants is now possible; pedigree analysis will be aided by the improved methodology.
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PMID:Phenotypic and molecular biological analysis of human butyrylcholinesterase variants. 225 36

A form of thyroxine-binding globulin (TBG) with reduced affinity for hormone and increased susceptibility to heat and acid denaturation has been identified in Australian Aborigines (TBG-A). Results of heat denaturation of TBG established that the TBGA allele is X linked and has a frequency of 50.9% in Western Australian Aborigines. The sequence of an isolated TBGA allele differed at two positions from that of the normal TBG allele (TBGC). One substitution was in codon 191, ACA (threonine) rather than GCA (alanine), and the other was in codon 283, TTT (phenylalanine) instead of TTG (leucine). These nucleotide substitutions resulted in the loss of sites for the enzymes Bgl 1 and Tth 111 II, respectively. The nucleotide substitutions in the TBG-A allele was confirmed by digestion of genomic DNA segments amplified using the polymerase chain reaction. The Bgl 1 and Tth 111 II sites were absent in the genes of two Aboriginal men expressing TBG-A and were present in those of three Aboriginal and six Caucasian males expressing TBG-C. The TBG gene of a seventh Caucasian male possessed the Bgl 1 site but had lost the Tth 111 II site; sequencing of this allele revealed only the substitution in codon 283 identical to that in the TBGA allele. As the biochemical properties of TBGPhe-283 expressed by this individual were indistinguishable from normal TBGLeu-283, we believe that the abnormal properties of TBG-A are due to substitution of alanine for threonine at residue 191.
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PMID:Sequence of the variant thyroxine-binding globulin of Australian aborigines. Only one of two amino acid replacements is responsible for its altered properties. 249 3

A novel mutation of the N-RAS gene of T-ALL blast cells was detected by a direct sequencing of in vitro amplified exon-1 of the N-RAS gene. Threonine (ACA) was substituted for alanine (GCA) at codon 11. This mutation would have been overlooked by conventional probe hybridization techniques. A search for other mutations in N-RAS exon-1 in T-ALL revealed a codon 13 mutation substituting aspartic acid (GAT) for glycine (GGT) in one of 18 patients. No mutations at codon 12 were detected.
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PMID:N-RAS mutations in T-cell acute lymphocytic leukaemia: analysis by direct sequencing detects a novel mutation. 266 Sep

The nucleotide sequence of the spc determinant of the Staphylococcus aureus transposon Tn554 has been determined. This gene encodes a spectinomycin adenyltransferase, AAD(9), that mediates resistance to spectinomycin but not to streptomycin. The sequence predicts a 260 amino acid protein of molecular weight 28,943. A spectinomycin-sensitive mutant (spc-1) contains a G----A transition resulting in substitution of threonine (ACA) for alanine (GCA) at residue 165. The predicted amino acid sequence is 36% homologous to that of a widely distributed, gram-negative streptomycin/spectinomycin adenyltransferase, AAD(3") (9), specified by the aadA determinant (Holingshead and Vapnek 1985).
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PMID:Nucleotide sequence of a spectinomycin adenyltransferase AAD(9) determinant from Staphylococcus aureus and its relationship to AAD(3") (9). 299 13

The efficiency of translation of the cII gene of bacteriophage lambda is greatly reduced by the cII3059 mutation, a GUU----GAU (Val----Asp) change in the second cII codon. Mutations in the third and fourth codons of the cII gene, called ctr mutations, reverse this translation deficiency. Lambda cII3059 ctr-1, which has a GCA----ACA (Ala----Thr) change in the fourth cII codon, produces about half the normal level of cII activity in liquid cultures, and lambda cII3059 ctr-2 and lambda cII3059 ctr-3, which have identical CGT----CGC changes in the third codon, produce normal levels of cII activity in liquid culture. Since the cII protein of ctr-3 has the same primary sequence as that of lambda cII3059, the cII- phenotype of lambda cII3059 can be explained entirely by the deficiency of translating cII mRNA. We propose that ctr mutations increase translation efficiency by destabilizing a stable stem structure which can be formed by cII mRNA. The ctr mutations lie in an overlapping regulatory region which contains, in addition to sequence elements that influence the rate of cII translation, a region to which cII protein binds to activate transcription from the PRE promoter. The ctr-1 mutation alters the cII recognition sequence from 5'-T-T-G-C-N6T-T-G-C-3' to 5'-T-T-G-C-N6T-T-G-T-3', but has no effect on PRE activity. Since a C----T change in the first (5'-proximal) T-T-G-C sequence (to yield 5'-T-T-G-T-N6T-T-G-C) greatly lowers cII binding affinity, cII protein must not recognize the two T-T-G-C sequences in an identical manner.
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PMID:Mutations that alter the DNA binding site for the bacteriophage lambda cII protein and affect the translation efficiency of the cII gene. 624 Dec 64

Mouse immunoglobulin heavy-chain variable region (Ig VH) genes apparently arose from the approximately 600-base-pair-long (approximately 12 tandem repeats of the 48-base-pair-long primordial building block sequence TTC-AGC-AGC-CTG-ACT-GGA-TAT-GAC-CTG-GAG-TGG-ACT-TAC-TGC-GCA-AGA) that in the original reading frame specified the amino acid sequence Phe-Ser-Ser-Leu-Thr-Gly-Tyr-Asp-Leu-Glu-Trp-Thr-Tyr-Cys-Ala-Arg. The previously identified, shorter prototype building blocks merely represented particular portions of the above primordial sequence. Even today, the direct descendant in toto of this primordial sequence specifies the last one-sixth of each VH coding sequence: the 83rd to 98th amino acid residues. Furthermore, its four truncated derivatives specify the 4th to 14th, 17th to 23rd, 29th to 37th, and 38th to 48th amino acid residues. Accordingly, all three relatively invariant--therefore, conserved--framework regions (FW-1, FW-2, and FW-3) of VHs are specified by recognizable--therefore, conserved--descendants of the primordial sequence.
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PMID:Identification of the 48-base-long primordial building block sequence of mouse immunoglobulin variable region genes. 680 49


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