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.
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http://dx.doi.org/10.1111/j.1365-2958.2011.07793.x | DOI Listing |
Nucleic Acids Res
January 2025
Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa-shi, Chiba 277-8562, Japan.
IUBMB Life
January 2025
Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India.
Initiation factors play critical roles in fine-tuning translation initiation, which is the first and the rate-limiting step in protein synthesis. In bacteria, initiation factors, IF1, IF2 and IF3 work in concert to accurately position the initiator tRNA (i-tRNA) in its formyl-aminoacyl form, and the mRNA start codon at the ribosomal P-site, setting the stage for accommodation of the aminoacyl-tRNA in response to the second codon, and formation of the first peptide bond. Among these, IF3 is particularly crucial in ensuring the fidelity of translation initiation as it is involved in the accuracy of the selection of i-tRNA and the start codon.
View Article and Find Full Text PDFbioRxiv
September 2024
Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain.
The initiation phase is the rate-limiting step of protein synthesis (translation) and is finely regulated, making it an important drug target. In bacteria, initiation is guided by three initiation factors and involves positioning the start site on the messenger RNA within the P-site on the small ribosomal subunit (30S), where it is decoded by the initiator tRNA. This process can be efficiently inhibited by GE81112, a natural hydrophilic, noncyclic, nonribosomal tetrapeptide.
View Article and Find Full Text PDFSoc Sci Med
November 2024
Business School, Sichuan University, Sichuan, China. Electronic address:
Background: Career fulfilment among medical doctors is crucial for job satisfaction, retention, and healthcare quality, especially in developing nations with challenging healthcare systems. Traditional career guidance methods struggle to address the complexities of career fulfilment. While recent advancements in machine learning, particularly Artificial Neural Network (ANN) models, offer promising solutions for personalized career predictions, their applicability, interpretability, and impact remain challenging.
View Article and Find Full Text PDFPLoS Pathog
August 2024
Institute for Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany.
RNA degradation is an essential process that allows bacteria to regulate gene expression and has emerged as an important mechanism for controlling virulence. However, the individual contributions of RNases in this process are mostly unknown. Here, we tested the influence of 11 potential RNases in the intestinal pathogen Yersinia pseudotuberculosis on the expression of its type III secretion system (T3SS) and associated effectors (Yops) that are encoded on the Yersinia virulence plasmid.
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