HMM Summary Page: TIGR00431

FunctiontRNA pseudouridine(55) synthase
Gene SymboltruB
Trusted Cutoff151.45
Domain Trusted Cutoff151.45
Noise Cutoff58.10
Domain Noise Cutoff58.10
Isology Typeequivalog
EC Number5.4.99.25
HMM Length210
Mainrole CategoryProtein synthesis
Subrole CategorytRNA and rRNA base modification
Gene Ontology TermGO:0004730: pseudouridylate synthase activity molecular_function
GO:0006400: tRNA modification biological_process
GO:0016870: intramolecular transferase activity, transferring other groups molecular_function
AuthorHaft DH
Entry DateApr 20 1999 2:06PM
Last ModifiedDec 19 2011 11:25AM
CommentTruB, the tRNA pseudouridine 55 synthase, converts uracil to pseudouridine in the T loop of most tRNAs in all three domains of life. This model is built on a seed alignment of bacterial proteins only. Saccharomyces cerevisiae protein YNL292w (Pus4) has been shown to be the pseudouridine 55 synthase of both cytosolic and mitochondrial compartments, active at no other position on tRNA and the only enzyme active at that position in the species. A distinct yeast protein YLR175w, (centromere/microtubule-binding protein CBF5) is an rRNA pseudouridine synthase, and the archaeal set is much more similar to CBF5 than to Pus4. It is unclear whether the archaeal proteins found by this model are tRNA pseudouridine 55 synthases like TruB, rRNA pseudouridine synthases like CBF5, or (as suggested by the absence of paralogs in the Archaea) both. CBF5 likely has additional, eukaryotic-specific functions. The trusted cutoff is set above the scores for the archaeal homologs of unknown function, so yeast Pus4p scores between trusted and noise.
ReferencesSE TIGR GA hmmls AL clustalw_manual DR HAMAP; MF_01081; 2 of 26