The role of GTP in transient splitting of 70S ribosomes by RRF (ribosome recycling factor) and EF-G (elongation factor G).
The role of GTP in transient splitting of 70S ribosomes by RRF (ribosome recycling factor) and EF-G (elongation factor G).
复制标题
GTP在RRF（核糖体回收因子）和EF-G（伸长因子G）中GTP在70S核糖体瞬时分裂中的作用。
DOI：
10.1093/nar/gkn647
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发表时间：
2008-12
影响因子：
14.9
通讯作者：
Kaji H
中科院分区：
文献类型：
--
作者：
Hirokawa G;Iwakura N;Kaji A;Kaji H
核糖体再循环因子（RRF）、延伸因子G（EF-G）和GTP将70 S核糖体分成亚基。在这里，我们证明了分裂是短暂的，GTP的耗尽导致分裂亚基重新结合成70 S核糖体，除非IF 3（起始因子3）存在。然而，如果RRF、EF-G和GTP存在于蔗糖密度梯度离心（SDGC）缓冲液中，则在不含IF 3的SDGC中观察到裂解。70 S核糖体的分裂导致核糖体的光散射减少。从光散射研究中获得的动力学常数足以解释在对数期核糖体激活的滞后期期间RRF和EF-G/GTP对70 S核糖体的分裂。随着70 S核糖体数量的增加，裂解70 S核糖体所需的RRF、EF-G和GTP也随之增加。在生理量的多胺、GTP和因子存在下，甚至0.6 μM 70 S核糖体（比常规测定的70 S核糖体高12倍）也被分裂。亚精胺（2 mM）完全抑制IF 3的抗结合活性和70 S核糖体的RRF/EF-G/GTP依赖性分裂。
Ribosome recycling factor (RRF), elongation factor G (EF-G) and GTP split 70S ribosomes into subunits. Here, we demonstrated that the splitting was transient and the exhaustion of GTP resulted in re-association of the split subunits into 70S ribosomes unless IF3 (initiation factor 3) was present. However, the splitting was observed with sucrose density gradient centrifugation (SDGC) without IF3 if RRF, EF-G and GTP were present in the SDGC buffer. The splitting of 70S ribosomes causes the decrease of light scattering by ribosomes. Kinetic constants obtained from the light scattering studies are sufficient to account for the splitting of 70S ribosomes by RRF and EF-G/GTP during the lag phase for activation of ribosomes for the log phase. As the amount of 70S ribosomes increased, more RRF, EF-G and GTP were necessary to split 70S ribosomes. In the presence of a physiological amount of polyamines, GTP and factors, even 0.6 μM 70S ribosomes (12 times higher than the 70S ribosomes for routine assay) were split. Spermidine (2 mM) completely inhibited anti-association activity of IF3, and the RRF/EF-G/GTP-dependent splitting of 70S ribosomes.
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影响因子：
4.5
作者：
Grentzmann, G;Kelly, PJ;Kaji, A
通讯作者：
Kaji, A
影响因子：
11.4
作者：
Janosi, L;Mottagui-Tabar, S;Kaji, A
通讯作者：
Kaji, A
影响因子：
4.9
作者：
Hirokawa, Go;Kaji, Hideko;Kaji, Akira
通讯作者：
Kaji, Akira
DOI：
10.1073/pnas.76.7.3174
发表时间：
1979-01-01
影响因子：
11.1
作者：
JELENC, PC;KURLAND, CG
通讯作者：
KURLAND, CG
影响因子：
11.4
作者：
Freistroffer, DV;Pavlov, MY;Ehrenberg, M
通讯作者：
Ehrenberg, M