| Autor: |
Harald Putzer, Soumaya Laalami, Karen Shahbabian, Patrice Bruscella |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
Molecular Microbiology. 81:1526-1541 |
| ISSN: |
0950-382X |
| DOI: |
10.1111/j.1365-2958.2011.07793.x |
| Popis: |
RNase Y is a novel endoribonuclease affecting global mRNA metabolism. We show that this nuclease affects the expression of the Bacillus subtilis infC-rpmI-rplT operon, encoding translation initiation factor IF3 and the ribosomal proteins L35 and L20. This operon is autoregulated by a complex L20-dependent transcription attenuation mechanism. L20 binds to a phylogenetically conserved domain on the 5' untranslated region of the infC mRNA which mimics the L20 binding sites on 23S rRNA. We have identified a second promoter (P1) upstream of the previously identified promoter (P2). The P1, but not the P2, readthrough transcript is stabilized in a strain depleted for RNase Y. However, under these conditions infC biosynthesis is repressed threefold. We show that the unprocessed P1 transcript is non-functional for IF3 translation but fully competent to express the co-transcribed ribosomal protein genes. RNase Y cleavage of the P1 transcript creates an entry site for the 5'-3' exonucleolytic activity of RNase J1 which degrades the infC mRNA when translation initiation efficiency is low. A second RNase Y cleavage is crucial for initiating degradation of the prematurely terminated infC leader RNAs, including the L20 operator complex, which permits efficient recycling of the L20 protein. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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