Expression of the human argininosuccinate synthetase gene in hamster transferents.
AUTOR(ES)
Hudson, L D
RESUMO
The structural gene for human argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5] was transferred to argininosuccinate synthetase-deficient 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 in 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 arginonosuccinate 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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=349806Documentos Relacionados
- Amplification of hypoxanthine-guanine phosphoribosyltransferase genes in chromosome-mediated gene transferents.
- Molecular structure of the human argininosuccinate synthetase gene: occurrence of alternative mRNA splicing.
- Molecular analysis of argininosuccinate synthetase deficiency in human fibroblasts.
- Sequence for human argininosuccinate synthetase cDNA.
- Conservation of structure in the human gene encoding argininosuccinate synthetase and the argG genes of the archaebacteria Methanosarcina barkeri MS and Methanococcus vannielii.
