ISSN:
1420-9071
Keywords:
Cysteine
;
glutathione
;
protein synthesis
;
aspartate
;
thiols
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract The ability of nonprotein thiols to modulate rates of protein synthesis was investigated in isolated rat hepatocytes. Addition of cysteine stimulates protein labelling by [14C] Leucine. Glutahione depletion, induced by in vivod administration of L-buthionine sulfoximine and diethylmaleate, did not alter the effect of cysteine, although it decreased the rate of protein synthesis by 32%. The effect of cysteine on protein synthesis does not seem to be related to a perturbatin of the redox state of the NAD+/NADH system or to changes in the rate of gluconeogenic pathway. The following observations indicate that cysteine may stimulate protein syntheis by increasing intracellular levels of aspartate: 1. Amino-oxyacetate, an inhibitor of pyridoxyal-dependent enzymes, inhibits protein labelling and decreases aspartate cellular content, whereas most amino acids accumulate or remain unchanged; 2. Cysteine, in the absence or in the presence of amino-ocycetate, stimulates protein labelling and induces aspartate accumulation, although mot amino acids diminish or remain unchanged.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01923353
Permalink