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Updated: Jan 7, 2026

Nanomanipulation of Single RNA Molecules by Optical Tweezers

Nanomanipulation of Single RNA Molecules by Optical Tweezers

Published on: August 20, 2014

Bacillus subtilis glmSリボザイムの準安定折り畳みはRNase J1によるターンオーバーを調節する

Yuan Lou¹, Sarah A Woodson¹

¹T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218 USA.

Journal of molecular biology

|December 25, 2025

Abstract:

Rapid turnover of glmS mRNA in Bacillus subtilis by 5'-3' exoribonuclease RNase J is essential for feedback regulation of glucosamine-6-phosphate (GlcN6P) synthase expression, upon self-cleavage of a GlcN6P-activated ribozyme in the glmS 5' UTR. We used biochemical assays and single molecule fluorescence microscopy to show that initiation of RNase J decay is inefficient and requires approximately 15 5' unpaired nucleotides to form a processive exonuclease complex that is insensitive to downstream RNA structure. When stably folded, the cleaved glmS ribozyme blocks RNase J initiation. However, co-transcriptional ribozyme cleavage and physiological Mg²⁺ levels increase decay by weakening the ribozyme structure. At 22 ˚C, the processive velocity of RNase J, 23 ± 8 nt/s, is equal or faster than transcription, indicating that RNase J has the potential to catch elongating polymerases. The results show how the folding stability of 5' mRNA structure contributes to RNase J recognition and the control of mRNA half-life.

キーワード:

RNA分解 RNAエキソヌクレアーゼ細菌mRNAターンオーバー glmSリボザイム一分子蛍光顕微鏡

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