Chromosome assignment of a human gene for argininosuccinate synthetase expression in Chinese hamster X human somatic cell hybrids

Carritt, B.; Goldfarb, Peter S.; Hooper, Martin; Slack, C.

doi:10.1016/0014-4827(77)90242-7

Cited by 45 publications

(13 citation statements)

References 16 publications

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“…The human gene is located on chromosome 9, and the incidence rate is approximately one in 100,000 [59,60]. Most patients present during the early neonatal period with acute hyperammonemia, and highly elevated plasma citrulline is the hallmark of this disorder.…”

Section: Argininosuccinate Synthetasementioning

confidence: 99%

Contrasting features of urea cycle disorders in human patients and knockout mouse models

Deignan

Cederbaum

Grody

2008

Molecular Genetics and Metabolism

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The urea cycle exists for the removal of excess nitrogen from the body. Six separate enzymes comprise the urea cycle, and a deficiency in any one of them causes a urea cycle disorder (UCD) in humans. Arginase is the only urea cycle enzyme with an alternate isoform, though no known human disorder currently exists due to a deficiency in the second isoform. While all of the UCDs usually present with hyperammonemia in the first few days to months of life, most disorders are distinguished by a characteristic profile of plasma amino acid alterations that can be utilized for diagnosis. While enzyme assay is possible, an analysis of the underlying mutation is preferable for an accurate diagnosis. Mouse models for each of the urea cycle disorders exist (with the exception of NAGS deficiency), and for almost all of them, their clinical and biochemical phenotypes rather closely resemble the phenotypes seen in human patients. Consequently, all of the current mouse models are highly useful for future research into novel pharmacological and dietary treatments and gene therapy protocols for the management of urea cycle disorders.

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Section: Argininosuccinate Synthetasementioning

confidence: 99%

Contrasting features of urea cycle disorders in human patients and knockout mouse models

Deignan

Cederbaum

Grody

2008

Molecular Genetics and Metabolism

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“…Argininosuccinate synthetase activity has not been detected in any cultured hamster fibroblast line (21,29,30), although it is present in hamster epithelial cells (30) as well as in most other cultured mammalian cells. This naturally occurring enzyme deficiency presumably reflects the differentiated state of the tissue from which the cells arise or else it results from mutation in the gene or extinction of synthetase activity early in culture.…”

mentioning

confidence: 99%

“…Like other hamster fibroblasts, the hamster recipient a23 does not express argininosuccinate synthetase (21) (22) was the generous gift of B. Carritt. The human lymphoblast line MGL8B2 is a twice reisolated derivative of MGL8 (18) and is the parent of the canavanine-resistant variant MGL8D1 (19 Nonidet P40 (Bethesda Research Laboratories, Rockville, MD), and layered over 1 M sucrose containing 20mM Tris-HCl (pH 7.4), 2 mM CaCl2, and 0.2% Nonidet P40 at 4VC.…”

mentioning

confidence: 99%

Expression of the human argininosuccinate synthetase gene in hamster transferents.

Hudson¹,

Erbe²,

Jacoby³

1980

Proc. Natl. Acad. Sci. U.S.A.

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The structural gene for human argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5] was transferred to argininosuccinate synthetasedeficient Chinese hamster cells via metaphase chromosomes isolated-from human lymphoblast line MGL8D1, a constitutive overproducer of argininosuccinate synthetase, and from its repressible parent, MGL8B2. Argininosuccinate synthetase expression was selected for ih citrulline-containing medium, and the human origin of the argininosuccinate synthetase expressed by seven transferents was identified by isoelectric focusing. Stable transferents expressing MGL8D1 argininosuccinate synthetase fell into two classes: (i) those whose argininosuccinate synthetase activity was reduced to 10-50% by arginine, similar to the repression of argininosuccinate synthetase synthesis observed in normal human lymphoblasts, and (ii) those that constitutively expressed argininosuccinate synthetase when grown in the presence of arginine or citrulline. Two transferents from the MGL8B2 donor constitutively expressed human argininosuccinate synthetase. Three hamster revertants were isolated that constitutively expressed hamster argininosuccinate synthetase. Transferents and revertants exhibited growth-dependent changes in argininosuccinate synthetase activity, in contrast to the constant synthetase activity levels in donor lymphoblasts during growth. The isolation of stable transferents that constitutively or repressibly express argininosuccinate synthetase makes possible the analysis of regulatory signals influencing expression of the argininosuccinate synthetase gene.Functional genes can be transferred to mammalian cells and stably transmitted to progeny cells when either metaphase chromosomes (1-11) or DNA (12-16) is incubated with recipient cells. Stable transferents appear to have integrated the donor gene into their genomes with no apparent site specificity (7)(8)(9)13). The integrated DNA, estimated to represent less than 0.25% of the haploid donor genome in chromosome transfer experiments (4-6) and approximately 3.4 kilobases for the viral thymidine kinase gene (12,13), is large enough to include regulatory sequences adjacent to the structural gene sequence(s). These features of gene transfer make it attractive for analyzing regulatory signals influencing gene expression, as well as for mapping these regulatory sequences.We have transferred the human gene for the urea cycle enzyme argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5], which has been localized to the distal portion of the long arm of chromosome 9 (17), to enzyme-deficient hamster fibroblasts and examined the regulation of the argininosuccinate synthetase expressed in transferent cells. The synthesis of argininosuccinate synthetase in human lymphoblast line MGL8B2 is normally repressed when arginine is present in the medium (18). Constitutive overproducers of argininosuccinate synthetase, however, have been isolated by selecting human lymphoblasts resistant to c...

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“…DNA fragments and RNA molecules were detected by hybridization to the 32P-labeled 1.5 kb insert from pAS1, the plasmid containing the cDNA for argininosuccinate synthetase (8 (8) and that the genes map to at least 10 different human chromosomes (9), including chromosome 9, X, and 6. Expression of argininosuccinate synthetase activity has been mapped to human chromosomes 9 (15), and although we have considered this assignment open to some question (9), we believe that it is correct. We have assigned the largest 31-kb fragment in the EcoRI blot pattern and also the 3.9 kb and 2.7 kb fragments in the HindIII digest to chromosome 9.…”

Section: Introductionmentioning

confidence: 96%

Molecular analysis of argininosuccinate synthetase deficiency in human fibroblasts.

Su¹,

Bock²,

Beaudet³

et al. 1982

J. Clin. Invest.

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A B S T R A C T We have analyzed cultured skin fibroblasts derived from patients with argininosuccinate synthetase deficiency for alterations in gene structure, mRNA content, and protein structure. Genomic DNA was digested with the endonucleases EcoRI or HindIII, and the fragments were analyzed by Southern blotting and hybridization with a cDNA probe for argininosuccinate synthetase. The blot pattern is complex because there are at least 10 copies of argininosuccinate synthetase-like genes scattered over multiple human chromosomes. All nine patients studied showed patterns of DNA fragments that were indistinguishable from the normal control cell lines, and despite the possibility that the complexity could mask some changes, major deletions of the active gene(s) were not present. Blot hybridization of RNA indicated the presence of hybridizable mRNA of approximately normal size in seven of seven individuals examined with a suggestion of some heterogeneity. Analysis of enzyme antigen by protein transfer from NaDodSO4 containing polyacrylamide gels revealed considerable heterogeneity. This analysis revealed no cross-reacting material (CRM) in nine cell lines, CRM of normal molecular weight in one cell line, and CRM of reduced molecular weight in one cell line. These findings suggest that the genes for argininosuccinate synthetase in most citrullinemia patients are transcribed and produce stable mRNA. These mRNA either are not translated, or the translation product (enzyme) is rapidly degraded or is immunologically nonreactive. Defective gene expression in this disorder appears to involve abnormal mRNA, which may be altered by point mutations, frame shift mutations, deletions, insertions or particularly by abnormal RNA processing.

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Chromosome assignment of a human gene for argininosuccinate synthetase expression in Chinese hamster X human somatic cell hybrids

Cited by 45 publications

References 16 publications

Contrasting features of urea cycle disorders in human patients and knockout mouse models

Contrasting features of urea cycle disorders in human patients and knockout mouse models

Expression of the human argininosuccinate synthetase gene in hamster transferents.

Molecular analysis of argininosuccinate synthetase deficiency in human fibroblasts.

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