Bercovich-Kinori Adi, Bibi Eitan
Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
J Cell Sci. 2015 Apr 1;128(7):1444-52. doi: 10.1242/jcs.166116. Epub 2015 Feb 4.
The signal recognition particle (SRP) receptor is a major player in the pathway of membrane protein biogenesis in all organisms. The receptor functions as a membrane-bound entity but very little is known about its targeting to the membrane. Here, we demonstrate in vivo that the Escherichia coli SRP receptor targets the membrane co-translationally. This requires emergence from the ribosome of the four-helix-long N-domain of the receptor, of which only helices 2-4 are required for co-translational membrane attachment. The results also suggest that the targeting might be regulated co-translationally. Taken together, our in vivo studies shed light on the biogenesis of the SRP receptor and its hypothetical role in targeting ribosomes to the E. coli membrane.
信号识别颗粒（SRP）受体是所有生物体中膜蛋白生物合成途径的主要参与者。该受体作为一种膜结合实体发挥作用，但关于其靶向膜的机制却知之甚少。在此，我们在体内证明了大肠杆菌SRP受体在共翻译过程中靶向膜。这需要受体的四螺旋长N结构域从核糖体中出现，其中只有螺旋2-4对于共翻译膜附着是必需的。结果还表明，靶向可能在共翻译过程中受到调节。综上所述，我们的体内研究揭示了SRP受体的生物合成及其在将核糖体靶向大肠杆菌膜中的假设作用。
