HMM Summary Page: TIGR02395

FunctionRNA polymerase sigma-54 factor
Gene SymbolrpoN
Trusted Cutoff277.35
Domain Trusted Cutoff277.35
Noise Cutoff158.45
Domain Noise Cutoff158.45
Isology Typeequivalog
HMM Length434
Mainrole CategoryTranscription
Subrole CategoryTranscription factors
Gene Ontology TermGO:0006352: transcription initiation, DNA-dependent biological_process
GO:0016987: sigma factor activity molecular_function
AuthorHaft DH
Entry DateDec 8 2004 10:11AM
Last ModifiedFeb 14 2011 3:27PM
CommentA sigma factor is a DNA-binding protein protein that binds to the DNA-directed RNA polymerase core to produce the holoenzyme capable of initiating transcription at specific sites. Different sigma factors act in vegetative growth, heat shock, extracytoplasmic functions (ECF), etc. This model represents the clade of sigma factors called sigma-54, or RpoN (unrelated to sigma 70-type factors such as RpoD/SigA). RpoN is responsible for enhancer-dependent transcription, and its presence characteristically is associated with varied panels of activators, most of which are enhancer-binding proteins (but see Brahmachary, et al., PMID:15231786). RpoN may be responsible for transcription of nitrogen fixation genes, flagellins, pilins, etc., and synonyms for the gene symbol rpoN, such as ntrA, reflect these observations
ReferencesRN [1] RM 2517036 RT The -24/-12 promoter comes of age. RA Thony B, Hennecke H. RL FEMS Microbiol Rev. 1989 Dec;5(4):341-57.
Genome PropertyGenProp0634: Sigma-54 (RpoN) systems (HMM)