The bacterial RNA ligase RtcB accelerates the repair process of fragmented rRNA upon releasing the antibiotic stress  

作　　者：Muhammad Ramzan Manwar Changjun Shao Xing Shi Jian Wang Qiang Lin Yigang Tong Yu Kang Jun Yu 

机构地区：[1]CAS Key Laboratory of Genome Sciences and Information,Beijing Institute of Genomics,Chinese Academy of Sciences,Beijing 100101,China [2]University of Chinese Academy of Sciences,Beijing 100190,China [3]Beijing Institute of Microbiology and Epidemiology,Beijing 100071,China

出　　处：《Science China(Life Sciences)》2020年第2期251-258,共8页中国科学（生命科学英文版）

基　　金：supported by the National Key Research and Development Program of China(2016YFC0903800);the National Scientific Foundation of China(31470180,31471237,31671350);the Programs of Beijing Municipal Science and Technology Project(Z171100001317011);the Scientific Research Project of Public Welfare Industry(2013FY114300,201402018);the Key Research Program of Frontier Sciences,the Chinese Academy of Sciences(QYZDY-SSWSMC017)。

摘　　要：RtcB, a highly conserved RNA ligase, is found in all three domains of life, and demonstrated to be an essential tRNA splicing component in archaea and metazoans. However, the biological functions of RtcB in bacteria, where there is no splicing, remains to be clarified. We first performed bioinformatics analysis which revealed highly conserved structures and presumably conserved functions of RtcB in bacteria. However, its orthologs only occur in ~0.5% of bacterial species across diverse phyla with significant signals of frequent horizontal transfer, highlighting its non-essential role in bacteria. Next, by constructing an rtcBknockout strain, we find that the removal of antibiotic stress induces a significant impact on rtcB expression in wild-type strain,and furthermore the depletion of RtcB(?RtcB strain) delays the recovery process. Our transcriptomic analysis, comprising the3′-end labeling of RNAs, highlights a significant increase in unmapped reads and cleaved rRNAs in the ?RtcB strain, particularly during recovery. Our observations suggest that the conserved RNA ligase RtcB, repairs damaged r RNAs following stress,which potentially saves energy and accelerates recovery of its host. We propose that acquisition of RtcB by diverse bacterial taxa provides a competitive advantage under stressful conditions.RtcB, a highly conserved RNA ligase, is found in all three domains of life, and demonstrated to be an essential tRNA splicing component in archaea and metazoans. However, the biological functions of RtcB in bacteria, where there is no splicing, remains to be clarified. We first performed bioinformatics analysis which revealed highly conserved structures and presumably conserved functions of RtcB in bacteria. However, its orthologs only occur in ～0.5% of bacterial species across diverse phyla with significant signals of frequent horizontal transfer, highlighting its non-essential role in bacteria. Next, by constructing an rtcBknockout strain, we find that the removal of antibiotic stress induces a significant impact on rtcB expression in wild-type strain,and furthermore the depletion of RtcB(?RtcB strain) delays the recovery process. Our transcriptomic analysis, comprising the3′-end labeling of RNAs, highlights a significant increase in unmapped reads and cleaved rRNAs in the ?RtcB strain, particularly during recovery. Our observations suggest that the conserved RNA ligase RtcB, repairs damaged r RNAs following stress,which potentially saves energy and accelerates recovery of its host. We propose that acquisition of RtcB by diverse bacterial taxa provides a competitive advantage under stressful conditions.

关 键 词：RtcB bacteria RNA LIGASE stress response RIBOSOMAL RNA RNA repair 

分 类 号：Q933[生物学—微生物学]