Murty C N, Verney E, Sidransky H
Biochem J. 1975 Oct;152(1):143-51. doi: 10.1042/bj1520143.
The activity of initiation factors obtained from free and membrane-bound polyribosomes of liver and of transplantable H5123 hepatoma of rats was investigated by using an assay of protein synthesis in vitro in which poly (U)-directed polyphenylalanine synthesis was measured. Initiation factors of membrane-bound polyribosomes prepared by using the anionic detergent deoxycholate exhibited less activity in incorporating [14C]phenylalanyltRNA into polypetides than did initiation factors of free polyribosomes. However, when membrane-bound polyribosomes were prepared after using the non-ionic detergent Triton X-100, no significant differences in activities in polyphenylalanine synthesis were observed between the initiation factors of free and membrane-bound polyribosomes. These results suggest that Triton X-100 is preferable to deoxycholate in the isolation of of initiation factors from polyribosomes. Initiation factors, prepared by using Triton X-100, of free polyribosomes of hepatoma exhibited greater activity in the stimulation of polyphenylalanine synthesis than did the initiation factors of free or membrane-bound polyribosomes of host livers or of membrane-bound polyribosomes of hepatomas.
利用体外蛋白质合成试验，通过检测聚（U）指导的聚苯丙氨酸合成，研究了从大鼠肝脏以及可移植的H5123肝癌的游离和膜结合多核糖体中获得的起始因子的活性。使用阴离子去污剂脱氧胆酸盐制备的膜结合多核糖体的起始因子，在将[14C]苯丙氨酰tRNA掺入多肽方面，比游离多核糖体的起始因子活性更低。然而，当使用非离子去污剂Triton X-100制备膜结合多核糖体时，游离和膜结合多核糖体的起始因子在聚苯丙氨酸合成活性方面未观察到显著差异。这些结果表明，在从多核糖体中分离起始因子时，Triton X-100比脱氧胆酸盐更可取。使用Triton X-100制备的肝癌游离多核糖体的起始因子，在刺激聚苯丙氨酸合成方面，比宿主肝脏的游离或膜结合多核糖体以及肝癌的膜结合多核糖体的起始因子活性更高。
