Section of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536, USA.
Mol Microbiol. 2011 Sep;81(6):1474-83. doi: 10.1111/j.1365-2958.2011.07784.x. Epub 2011 Aug 4.
Type III protein secretion systems (T3SSs), which have evolved to deliver bacterial proteins into nucleated cells, are found in many species of Gram-negative bacteria that live in close association with eukaryotic hosts. Proteins destined to travel this secretion pathway are targeted to the secretion machine by customized chaperones, with which they form highly structured complexes. Here, we have identified a mechanism that co-ordinates the expression of the Salmonella Typhimurium T3SS chaperone SicP and its cognate effector SptP. Translation of the effector is coupled to that of its chaperone, and in the absence of translational coupling, an inhibitory RNA structure prevents translation of sptP. The data presented here show how the genomic organization of functionally related proteins can have a significant impact on the co-ordination of their expression.
III 型蛋白分泌系统（T3SS）是一种进化而来的系统，能够将细菌蛋白输送到有核细胞中，它存在于许多与真核宿主密切相关的革兰氏阴性菌中。旨在通过这种分泌途径运输的蛋白质被定制的伴侣蛋白靶向分泌机器，与伴侣蛋白形成高度结构化的复合物。在这里，我们已经确定了一种协调沙门氏菌 Typhimurium T3SS 伴侣蛋白 SicP 和其同源效应物 SptP 表达的机制。效应物的翻译与伴侣蛋白的翻译偶联，在没有翻译偶联的情况下，抑制性 RNA 结构阻止 sptP 的翻译。这里呈现的数据表明，功能相关蛋白的基因组组织如何对其表达的协调产生重大影响。
