RNASE-III CLEAVAGES IN NONCODING LEADERS OF ESCHERICHIA-COLI TRANSCRIPTS CONTROL MESSENGER-RNA STABILITY AND GENETIC EXPRESSION
RNASE-III CLEAVAGES IN NONCODING LEADERS OF ESCHERICHIA-COLI TRANSCRIPTS CONTROL MESSENGER-RNA STABILITY AND GENETIC EXPRESSION
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DOI：
10.1016/0300-9084(90)90192-j
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发表时间：
1990-11-01
期刊：
影响因子：
3.9
通讯作者：
GRUNBERGMANAGO, M
中科院分区：
文献类型：
--
作者：
REGNIER, P;GRUNBERGMANAGO, M
大肠杆菌的rpsO-pnp、rnc-era-recO和metY-nusA-infB操纵子的初级转录物各自在第一个翻译基因的上游由RNA酶III加工，在由5'非编码前导序列形成的发夹结构中。 3个操纵子的mRNA（其5'末端基序已被RNase III去除）比在RNase III缺陷型菌株中积累的未切割的转录物显著更快地衰减。 在RNase III位点附近的二级启动子处起始的metY-nusA-infB操纵子的初级转录物的快速衰减表明RNase III切割位点上游的5'特征负责未切割RNA的稳定性。 RNA酶III通过去除稳定其mRNA的5'基序来自动控制其自身的表达。 类似地，多核苷酸磷酸化酶和蛋白质Era的合成也受RNA酶III切割的控制，RNA酶III切割触发其信使的降解。 RNase III在基因表达调控中的作用以及mRNA稳定化和RNase III加工引发的5'至3'衰变的可能机制进行了讨论。
The primary transcripts of the rpsO-pnp, rnc-era-recO and metY-nusA-infB operons of E coli are each processed by RNase III, upstream of the first translated gene, in hair-pin structures formed by the 5' non-coding leader. The mRNAs of the 3 operons, of which the 5' terminal motifs have been removed by RNase III, decay significantly more rapidly than the uncut transcripts which accumulate in the RNase III deficient strain. The rapid decay of a primary transcript of the metY-nusA-infB operon, initiated at a secondary promoter in the vicinity of the RNase III sites, suggests that the 5' features upstream of the RNase III cutting sites are responsible for the stability of the uncut RNAs. RNase III autocontrols its own expression by removing the 5' motif which stabilizes its mRNA. Similarly, the synthesis of polynucleotide phosphorylase and of protein Era are also controlled by RNase III cleavages which trigger the degradation of their messengers. The role of RNase III in the regulation of gene expression and the possible mechanisms of mRNA stabilization and of 5' to 3' decay initiated by RNase III processing are discussed.