[40] Preparation of a cell-free system from chinese hamster ovary cells that translates natural and synthetic messenger ribonucleic acid templates

1983 ◽  
pp. 629-635 ◽  
Author(s):  
Kivie Moldave ◽  
Itzhak Fischer
Keyword(s):  
Chinese Hamster Ovary ◽  
Ribonucleic Acid ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Free System ◽  
Ovary Cells ◽  
Cell Free System ◽  
Messenger Ribonucleic Acid ◽  
A Cell ◽  
Natural And Synthetic

scholarly journals The limiting factors of a cell-free protein-synthesizing system from rat brain

1970 ◽  
Vol 116 (1) ◽  
pp. 135-145 ◽  
Author(s):  
A. J. Dunn
Keyword(s):  
Rat Brain ◽  
Ribonucleic Acid ◽  
Limiting Factors ◽  
Contributory Factor ◽  
Free System ◽  
Chain Initiation ◽  
Cell Free System ◽  
Messenger Ribonucleic Acid ◽  
Low Concentrations ◽  
A Cell

The limiting factors of a cell-free system from rat brain for incorporating amino acids into protein were studied. The initial more rapid incorporation by microsomes, as opposed to that by ribosomes, is suggested to be due to damage of the ribosomes by detergent. The defect is rectifiable by incubation of the ribosomes in cell sap, so that ribosomes eventually incorporate more amino acid than do microsomes. This may be because ribonuclease, which is associated with the microsomes but removed by detergent treatment, inactivates the microsomal system. The factor that causes incorporation by microsomes to cease abruptly within 1h is not the lack of any precursor or of adenosine triphosphate, of the inactivation of cell-sap factors or the accumulation of inhibitory substances, but is a deficiency of usable messenger ribonucleic acid. Chain initiation in the system is negligible. Ribosomes also become jammed at the end of messenger ribonucleic acid molecules, unable to terminate protein chains. This eventually leads to jammed polyribosomes, which can be partially relieved by very low concentrations of puromycin. A study of the release of polypeptides synthesized in response to the addition of synthetic messengers did not provide any conclusive information on chain-termination sequences, but did indicate some phenomena that were artifacts. It is concluded that ribonuclease action is sufficient to account for all the deficiencies of the cell-free system, but a lack of chain initiation may be a contributory factor.

Sign in / Sign up

Export Citation Format

Share Document