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A processed noncoding RNA regulates an altruistic bacterial antiviral system.

ABSTRACT: The ? 10³? bacteriophages on Earth relentlessly drive adaptive coevolution, forcing the generation of protective mechanisms in their bacterial hosts. One such bacterial phage-resistance system, ToxIN, consists of a protein toxin (ToxN) that is inhibited in vivo by a specific RNA antitoxin (ToxI); however, the mechanisms for this toxicity and inhibition have not been defined. Here we present the crystal structure of the ToxN-ToxI complex from Pectobacterium atrosepticum, determined to 2.75-Å resolution. ToxI is a 36-nucleotide noncoding RNA pseudoknot, and three ToxI monomers bind to three ToxN monomers to generate a trimeric ToxN-ToxI complex. Assembly of this complex is mediated entirely through extensive RNA-protein interactions. Furthermore, a 2'-3' cyclic phosphate at the 3' end of ToxI, and catalytic residues, identify ToxN as an endoRNase that processes ToxI from a repetitive precursor but is regulated by its own catalytic product.

SUBMITTER: Blower TR

PROVIDER: S-EPMC4612426 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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A processed noncoding RNA regulates an altruistic bacterial antiviral system.

Blower Tim R TR Pei Xue Y XY Short Francesca L FL Fineran Peter C PC Humphreys David P DP Luisi Ben F BF Salmond George P C GP

Nature structural & molecular biology 20110116 2

The ≥ 10³⁰ bacteriophages on Earth relentlessly drive adaptive coevolution, forcing the generation of protective mechanisms in their bacterial hosts. One such bacterial phage-resistance system, ToxIN, consists of a protein toxin (ToxN) that is inhibited in vivo by a specific RNA antitoxin (ToxI); however, the mechanisms for this toxicity and inhibition have not been defined. Here we present the crystal structure of the ToxN-ToxI complex from Pectobacterium atrosepticum, determined to 2.75-Å reso ...[more]

PMID: 21240270

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A processed noncoding RNA regulates an altruistic bacterial antiviral system.

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A processed noncoding RNA regulates an altruistic bacterial antiviral system.

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