Genome Property Definition Page

NametmRNA trans-translation system
DescriptionDefective mRNA can lead to a stalled ribosome with no stop codon to release the mRNA and nascent polypeptide. A structural RNA called tmRNA (or SsrA), charged like a tRNA with an Ala, can restart stranslation. The tmRNA, while resembling a tRNA, contains a stretch that acts as mRNA with a short coding region and stop codon. The coding region encodes a 10-amino acid tag that marks the nascent protein, once released, for rapid degradation. Small protein B (SmpB) is required for tmRNA function and has no other known function.
JCVI RoleOther
Parent PropertyGenProp0197: protein biosynthesis
GenProp0301: protein degradation
GenProp0462: response to stress

Step NameStep NumRequiredEvidence (Method)Evidence Go Terms
tmRNA-binding protein SmpBSmpBYESTIGR00086 (HMM): SsrA-binding protein
SspB adaptor to clpXPsspBNOPF04386 (HMM): stringent starvation protein B
tmRNA structural RNAtmRNAYEStmRNA (RNA)

Parent Properties
GenProp0197protein biosynthesis
GenProp0301protein degradation
GenProp0462response to stress

Sibling Properties
GenProp0016selenocysteine system
GenProp0132transcription termination - antitermination Nus factors
GenProp0148release factor 2 programmed frameshift
GenProp0174ribosome, bacterial, large subunit
GenProp0175ribosome, bacterial, small subunit
GenProp0188GatABC aspartyl/glutamyl-tRNA(Asn/Gln) amidotransferase complex
GenProp0189tRNA-Gln direct aminoacylation
GenProp0258tRNA aminoacylation
GenProp0259tRNA-Asn direct aminoacylation
GenProp0304cysteine biosynthesis, tRNA-dependent
GenProp0634Sigma-54 (RpoN) systems
GenProp0692selenouridine-containing tRNA
GenProp0704tRNA U34 carboxymethylaminomethyl modification
GenProp0740translation initiation, bacterial
GenProp0741translation elongation, bacterial
GenProp0746translation termination, bacterial
GenProp0812rho-dependent termination
GenProp0251clpXP degradation machine
GenProp0684FtsH/HflKC protease complex
GenProp0833proteasome-targeting modification by pupylation
GenProp0834proteasome, bacterial
GenProp0835ATP-dependent protease HslVU
GenProp04826S RNA (eubacterial RNA polymerase regulator)
GenProp0648phage shock protein regulon