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)

In cloning human fetal globin cDNA in bacterial plasmids, we obtained a recombinant which contained a fragment of gammg-globin cDNA corresponding to the region from amino acid 99 to the poly A. We determined a sequence of 169 nucleotides which included the complete 3' non-coding region of the gamma-globin mRNA. The codon for amino acid 136 was GCA, indicating that this cloned fragment was derived from the Agamma-globin gene. In conjunction with the surrounding sequences, the GCA codon provides the Agamma-species with a unique CTGCAG hexanucleotide that is recognized by the restriction enzyme Pst I. The 3'-untranslated region of the gamma-globin mRNA consists of 90 nucleotides, and shares little homology with that of the human beta-globin mRNA. As in other mammalian mRNAs, a symmetrical sequence and the hexanucleotide AAUAAA are present.
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PMID:Sequence of the 3'-noncoding and adjacent coding regions of human gamma-globin mRNA. 31 63

In this paper we describe the construction of a yeast tRNACys UGA suppressor. After specific hydrolysis of the parent molecule, the first base of the anticodon GCA was replaced by a uracil. The resulting molecule, harboring a UCA anticodon, was injected into Xenopus laevis oocytes in order to test its biological activities. The level of aminoacylation was similar to that of the parent molecule. Readthrough of the UGA termination codon in beta-globin mRNA, coinjected with the tRNA, indicated suppressor activity; however, tRNACys (anticodon UCA) was a much less efficient suppressor than others tested under the same conditions. We see no post-transcriptional modification of the uracil in the anticodon wobble position after injection into oocytes. This may be related to the low suppressor activity; however, it is also possible that other features of tRNACys structure may be unadapted to efficient UCA anticodon function.
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PMID:Construction of a UGA suppressor tRNA by modification in vitro of yeast tRNACys. 636 71

We have isolated and sequenced chloroplast (chl) and cytoplasmic (cyt) cysteine tRNAs from Nicotiana rustica. Both tRNAs carry a GCA anticodon but beyond that differ considerably in their nucleotide sequences. One obvious distinction resides in the presence of N6-isopentenyladenosine (i6A) and 1-methylguanosine (m1G) at position 37 in chl and cyt tRNA(Cys) respectively. In order to study the potential suppressor activity of tRNAs(Cys) we used in vitro synthesized zein mRNA transcripts in which an internal UGA stop codon had been placed in either the tobacco rattle virus (TRV)- or tobacco mosaic virus (TMV)-specific codon context. In vitro translation was carried out in a messenger- and tRNA-dependent wheat germ extract. Both tRNA(Cys) isoacceptors stimulate read-through over the UGA stop codon, however, chl tRNA(GCA)Cys is more efficient than the cytoplasmic counterpart. The UGA in the two viral codon contexts is suppressed to about the same extent by either of the two tRNAs(Cys), whereas UGA in the beta-globin context is not recognized at all. The interaction of tRNA(GCA)Cys with UGA requires an unconventional G:A base pair in the wobble position, as postulated earlier for plant tRNA(G psi A)Tyr misreading the UAA stop codon. This is the first case that a cysteine-accepting tRNA has been characterized as a natural UGA suppressor.
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PMID:Cysteine tRNAs of plant origin as novel UGA suppressors. 852 47

Hb G-Coushatta [beta22(B4)Glu-->Ala] is found in geographically separated ethnic groups. Commonest along the Silk Road region of China but also present in the North American Coushatta, we sought to determine whether this variant had a unicentric or multicentric origin. We examined the haplotype of the beta-globin gene cluster in two Chinese families and in five Louisiana Coushatta heterozygous for this mutation. Chinese and Louisiana Coushatta had different haplotypes associated with the identical Hb G mutation. These haplotypes were defined by the presence of a HindIII restriction site in the Agamma-globin gene and AvaII restriction site in the beta-globin gene in Chinese subjects and their absence in the Louisiana Coushatta. We found a CAC at codon beta2 (beta-globin gene framework 1 or 2) linked to the Hb G-Coushatta gene in Chinese, and a CAT (framework 3) in Louisiana Coushatta, indicating different beta-globin gene frameworks. Both the Hb G-Coushatta mutation (GAA-->GCA) and the codon 2 CAC-->CAT polymorphism are normal delta-globin gene sequences, suggesting the possibility of gene conversion. We conclude that Hb G-Coushatta had at least two independent origins. This could be due to separate mutations at codon beta22 in Chinese and Louisiana Coushatta, a mutation at this codon and a beta-->delta conversion, or two beta-->delta gene conversion events.
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PMID:Genetic studies suggest a multicentric origin for Hb G-Coushatta [beta22(B4)Glu-->Ala]. 1008 86

Over the last few years, substantial progress has been made in developing strategies for the detection and characterization of various mutations causing beta-thalassemia. The Indian population comprises of numerous endogamous caste groups and beta-thalassemia is seen in almost all of them. Knowledge of the spectrum of beta-thalassemia mutations in the population is a prerequisite for successful implementation of a prevention programme. Among the different approaches available today, Denaturing Gradient Gel Electrophoresis (DGGE) offers a valid technical approach which is applicable for screening of known mutants and polymorphisms as well as in locating regions of DNA bearing unknown mutations. We analysed 356 unrelated beta-thalassemia heterozygotes by DGGE and detected 30 anomalous DGGE patterns. Fifteen mutations were characterized after sequencing 25 anomalous patterns. Of these, codon 10(GCC --> GCA) is a recently reported novel beta-thalassemia mutation while -28(A --> G) and codon 121(G --> T) are being reported for the first time in the Indian population. HbS and HbE also showed two anomalous DGGE patterns each. Framework (FW) linkage studies showed that four mutations were associated with different beta-globin gene frameworks. Linkage of IVSI-5(G --> C) and cap site +1(A --> C) to FW2 and 619-bp deletion to FW1 is being observed for the first time. Multiple DGGE patterns corresponding to the same mutation is one of the major drawbacks of this technique. In spite of this, if sufficient preliminary work has been carried out to compile a comprehensive catalogue of DGGE patterns; this is a powerful approach to characterize the mutation or to localize a small region of DNA in the case of rarer mutations.
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PMID:Potential of denaturing gradient gel electrophoresis for scanning of beta-thalassemia mutations in India. 1107 47

Thalassemias and hemoglobinopathies are very common among Southeast Asian populations, particularly in Thailand, where it is estimated that nearly 30% of the population carries at least one such disorder. Moreover, the heterogeneity of different mutant alpha- and beta-globin alleles contributes to the complexity in diagnosis and proper management, as more than 60 thalassemia syndromes and hemoglobinopathies have been described. Herein we report a further case of Hb G-Coushatta [beta22(B4)Glu-->Ala (GAA-->GCA)] (also known as G-Saskatoon, G-Hsin Chu and G-Taegu) in a Thai family in which the mother was found to have an unusual hemoglobin (Hb) anomaly in combination with Hb E [beta26(B8)Glu-->Lys, GAG-->AAG]. We applied our recently described polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique to scan the beta-globin genes and found an aberrant pattern in exon 1. The molecular analysis by direct genomic sequencing successfully identified the nucleotide mutation (codon 22, GAA-->GCA), and a novel amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) for this variant is described.
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PMID:Further identification of Hb G-Coushatta [beta22(B4)Glu-->Ala (GAA-->GCA)] in Thailand by the polymerase chain reaction-single-strand conformation polymorphism technique and by amplification refractory mutation system-polymerase chain reaction. 1736 10