Bugaeva Elizaveta Y, Shpanchenko Olga V, Felden Brice, Isaksson Leif A, Dontsova Olga A
Belozersky Institute, Build. A, Moscow State University, Moscow 119992, Russia.
FEBS Lett. 2008 Apr 30;582(10):1532-6. doi: 10.1016/j.febslet.2008.03.049. Epub 2008 Apr 7.
tmRNA and SmpB are the main participants of trans-translation, a process which rescues the ribosome blocked during translation of non-stop mRNA. While a one-to-one stoichiometry of tmRNA to the ribosome is generally accepted, the number of SmpB molecules in the complex is still under question. We have isolated tmRNA-ribosome complexes blocked at different steps of the tmRNA path through the ribosome and analyzed the stoichiometry of the complexes. Ribosome, tmRNA and SmpB were found in equimolar amount in the tmRNA-ribosome complexes stopped at the position of the 2nd, 4th, 5th or the 11th codons of the coding part of the tmRNA.
转运信使核糖核酸(tmRNA)和小稳定蛋白B(SmpB)是反式翻译的主要参与者,反式翻译是一个拯救在无终止信使核糖核酸(mRNA)翻译过程中受阻核糖体的过程。虽然一般认为tmRNA与核糖体的化学计量比为1:1,但该复合物中SmpB分子的数量仍存在疑问。我们分离了在tmRNA通过核糖体的不同步骤受阻的tmRNA-核糖体复合物,并分析了这些复合物的化学计量比。在tmRNA编码部分第2、4、5或第11个密码子位置处停止的tmRNA-核糖体复合物中,核糖体、tmRNA和SmpB的含量呈等摩尔比。