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RtcB, a novel RNA ligase, can catalyze tRNA splicing and HAC1 mRNA splicing in vivo.

ABSTRACT: RtcB enzymes are novel RNA ligases that join 2',3'-cyclic phosphate and 5'-OH ends. The phylogenetic distribution of RtcB points to its candidacy as a tRNA splicing/repair enzyme. Here we show that Escherichia coli RtcB is competent and sufficient for tRNA splicing in vivo by virtue of its ability to complement growth of yeast cells that lack the endogenous "healing/sealing-type" tRNA ligase Trl1. RtcB also protects yeast trl1? cells against a fungal ribotoxin that incises the anticodon loop of cellular tRNAs. Moreover, RtcB can replace Trl1 as the catalyst of HAC1 mRNA splicing during the unfolded protein response. Thus, RtcB is a bona fide RNA repair enzyme with broad physiological actions. Biochemical analysis of RtcB highlights the uniqueness of its active site and catalytic mechanism. Our findings draw attention to tRNA ligase as a promising drug target.

SUBMITTER: Tanaka N

PROVIDER: S-EPMC3162383 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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RtcB, a novel RNA ligase, can catalyze tRNA splicing and HAC1 mRNA splicing in vivo.

Tanaka Naoko N Meineke Birthe B Shuman Stewart S

The Journal of biological chemistry 20110711 35

RtcB enzymes are novel RNA ligases that join 2',3'-cyclic phosphate and 5'-OH ends. The phylogenetic distribution of RtcB points to its candidacy as a tRNA splicing/repair enzyme. Here we show that Escherichia coli RtcB is competent and sufficient for tRNA splicing in vivo by virtue of its ability to complement growth of yeast cells that lack the endogenous "healing/sealing-type" tRNA ligase Trl1. RtcB also protects yeast trl1Δ cells against a fungal ribotoxin that incises the anticodon loop of ...[more]

PMID: 21757685

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Dual functions of yeast tRNA ligase in the unfolded protein response: unconventional cytoplasmic splicing of HAC1 pre-mRNA is not sufficient to release translational attenuation.

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tRNA ligase structure reveals kinetic competition between non-conventional mRNA splicing and mRNA decay.

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The RNA-Splicing Ligase RTCB Promotes Influenza A Virus Replication by Suppressing Innate Immunity via Interaction with RNA Helicase DDX1.

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2022-10-10 | GSE190681 | GEO

RtcB is the RNA ligase component of an Escherichia coli RNA repair operon.

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A synthetic biology approach identifies the mammalian UPR RNA ligase RtcB.

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The RNA ligase RtcB reverses MazF-induced ribosome heterogeneity in Escherichia coli.

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Structures of RNA ligase RtcB in complexes with divalent cations and GTP.

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| S-EPMC9745838 | biostudies-literature

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