UniProt functional annotation for P69348



	UniProt functional annotation for P69348

UniProt code: P69348.

Organism: Escherichia coli (strain K12).

Taxonomy: Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales; Enterobacteriaceae; Escherichia.

Function: Toxic component of a type II toxin-antitoxin (TA) system. Its mode of function is controversial; it has been proposed to be an mRNA interferase but also an inhibitor of translation initiation. When overproduced in wild-type cells, inhibits bacterial growth and translation by cleavage of mRNA molecules while it has a weak effect on colony forming ability. Overproduction of Lon protease specifically activates YoeB-dependent mRNA cleavage, leading to lethality. YefM binds to the promoter region of the yefM-yeoB operon to repress transcription, YeoB acts as a corepressor.

Function: Shown in vitro to be an mRNA interferase that requires translation for substrate cleavage; if the mRNA is mutated so as to not be translatable it is no longer cleaved. Cleavage only occurs within translated regions. Has RNase activity and preferentially cleaves at the 3'-end of purine ribonucleotides. {ECO:0000269|PubMed:16109374}.

Function: Also shown in vitro to be a translation initiation blocker. Binds to the 70S ribosome and 50S ribosomal subunit; binding is inhibited by hygromycin A and tetracycline, both of which bind to the 30S subunit in the A site. Thus YoeB is located at the interface between 50S and 30S ribosomes and interacts with the A site where it cleaves mRNA, blocking translation initiation.

Subunit: Forms a complex with antitoxin YefM, in which the toxin is inactive. It has been described as being a YefM-YeoB(2) heterotrimer (PubMed:15980067). Also described as a YefM(2)-YoeB heterotrimer (PubMed:16109374 and PubMed:17170003). Binds the 50S ribosomal subunit. {ECO:0000269|PubMed:15980067, ECO:0000269|PubMed:16109374, ECO:0000269|PubMed:17170003}.

Induction: Repressed by YefM, more strongly repressed by the YefM(2)YoeB heterotrimer. Induced in persister cells. Ectopic expression of Salmonella or Shigella toxin VapC induces the yefM-yoeB operon and also induces Yoeb toxin activity in a Lon protease-dependent manner. {ECO:0000269|PubMed:16768798, ECO:0000269|PubMed:17170003, ECO:0000269|PubMed:19400780}.

Disruption phenotype: No visible phenotype under standard growth conditions. Delays Lon protease-dependent lethality upon overexpression of Lon, but does not fully suppress it. No loss of ability to form persister cells. {ECO:0000269|PubMed:15009896, ECO:0000269|PubMed:16768798}.

Similarity: Belongs to the YoeB family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Escherichia coli (strain K12).
Taxonomy:		Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales; Enterobacteriaceae; Escherichia.



Function:		Toxic component of a type II toxin-antitoxin (TA) system. Its mode of function is controversial; it has been proposed to be an mRNA interferase but also an inhibitor of translation initiation. When overproduced in wild-type cells, inhibits bacterial growth and translation by cleavage of mRNA molecules while it has a weak effect on colony forming ability. Overproduction of Lon protease specifically activates YoeB-dependent mRNA cleavage, leading to lethality. YefM binds to the promoter region of the yefM-yeoB operon to repress transcription, YeoB acts as a corepressor.



Function:		Shown in vitro to be an mRNA interferase that requires translation for substrate cleavage; if the mRNA is mutated so as to not be translatable it is no longer cleaved. Cleavage only occurs within translated regions. Has RNase activity and preferentially cleaves at the 3'-end of purine ribonucleotides. {ECO:0000269\|PubMed:16109374}.



Function:		Also shown in vitro to be a translation initiation blocker. Binds to the 70S ribosome and 50S ribosomal subunit; binding is inhibited by hygromycin A and tetracycline, both of which bind to the 30S subunit in the A site. Thus YoeB is located at the interface between 50S and 30S ribosomes and interacts with the A site where it cleaves mRNA, blocking translation initiation.


Subunit:		Forms a complex with antitoxin YefM, in which the toxin is inactive. It has been described as being a YefM-YeoB(2) heterotrimer (PubMed:15980067). Also described as a YefM(2)-YoeB heterotrimer (PubMed:16109374 and PubMed:17170003). Binds the 50S ribosomal subunit. {ECO:0000269\|PubMed:15980067, ECO:0000269\|PubMed:16109374, ECO:0000269\|PubMed:17170003}.
Induction:		Repressed by YefM, more strongly repressed by the YefM(2)YoeB heterotrimer. Induced in persister cells. Ectopic expression of Salmonella or Shigella toxin VapC induces the yefM-yoeB operon and also induces Yoeb toxin activity in a Lon protease-dependent manner. {ECO:0000269\|PubMed:16768798, ECO:0000269\|PubMed:17170003, ECO:0000269\|PubMed:19400780}.
Disruption phenotype:		No visible phenotype under standard growth conditions. Delays Lon protease-dependent lethality upon overexpression of Lon, but does not fully suppress it. No loss of ability to form persister cells. {ECO:0000269\|PubMed:15009896, ECO:0000269\|PubMed:16768798}.
Similarity:		Belongs to the YoeB family. {ECO:0000305}.