[Dependence of the level of gene expression in E. coli on the structure of the translation initiation segment (TIR)]. / Zavisimost' urovnia ékspressii gena v E. coli ot struktury uchastka initsiatsii transliatsii (TIR).

The expression levels of genes that are transcribed to give mRNAs with identical leader sequences and even with identical extended coding regions may differ considerably. In order to determine the mechanism of this phenomenon, secondary structures of some mRNAs synthesized from a series of expression plasmids were studied. It was shown that the effect of the mRNA secondary structure in the translation initiation region on the initiation efficiency is due not only to the hairpin formation in this region but also to long-range interactions. When complementary structures tighter than those resulted from the interaction of regions SD, UB1, UB2, and DB with 16S rRNA are formed, the efficiency of the translation initiation and, consequently, the expression level decrease.