RegulonDB RegulonDB 10.8:Regulon Page
   

CadC DNA-binding transcriptional activator

Synonyms: CadC
Summary:
CadC is a metal-sensitive transcriptional activator that regulates the expression of genes involved in cadaverine synthesis and excretion under low external pH and high concentrations of lysine [3, 5]. Two binding sites for CadC, Cad1 and Cad2, have been determined in the cadBA operon. While Cad1 contains an inverted repeat sequence and has a preference for AT-rich regions [], Cad2 lacks either an inverted repeat or a palindromic sequence. Both binding sites are necessary for cadBA activation. Under aerobic conditions, H-NS represses the cadBA operon. Upon binding to Cad1, CadC releases bound H-NS molecules, dissolving the H-NS repressor complex and allowing RNA polymerase binding. Transcription of cadBA is finally activated once a molecule of CadC binds to Cad2 [5]. CadC is an integral membrane protein that belongs to the ToxR-like family of transcriptional activators. It features a cytoplasmic DNA-binding N-terminal domain, a transmembrane domain, and a periplasmic C-terminal domain [5].
Read more >


Transcription factor      
TF conformation(s):
Name Conformation Type TF-Effector Interaction Type Apo/Holo Conformation Evidence (Confirmed, Strong, Weak) References
CadC Functional   [IMP] [1], [2], [3]
Evolutionary Family: OmpR
Sensing class: External sensing using transported metabolites
Connectivity class: Local Regulator
Gene name: cadC
  Genome position: 4360396-4361934
  Length: 1539 bp / 512 aa
Operon name: cadC
TU(s) encoding the TF:
Transcription unit        Promoter
cadC
cadCp


Regulon       
Regulated gene(s) cadA, cadB, cadC
Multifun term(s) of regulated gene(s) MultiFun Term (List of genes associated to the multifun term)
pH (1)
Porters (Uni-, Sym- and Antiporters) (1)
membrane (1)
amino acids (1)
Transcription related (1)
Read more >
Regulated operon(s) cadBA, cadC
First gene in the operon(s) cadB, cadC
Simple and complex regulons ArcA,CadC,GadE-RcsB,GadX,H-NS,Lrp,OmpR
CadC,FNR,H-NS,LeuO,MlrA,OmpR
Simple and complex regulatory phrases Regulatory phrase (List of promoters regulated by the phrase)
[CadC,+](2)


Transcription factor regulation    


Transcription factor binding sites (TFBSs) arrangements
      

  Functional conformation Function Promoter Sigma factor Central Rel-Pos Distance to first Gene Genes Sequence LeftPos RightPos Evidence (Confirmed, Strong, Weak) References
  CadC activator cadBp Sigma70 nd nd cadB, cadA nd nd [BPP], [GEA] [3], [4], [5]
  CadC activator cadCp Sigma70 nd nd cadC nd nd [GEA] [3]


Evolutionary conservation of regulatory elements    
     Note: Evolutionary conservation of regulatory interactions and promoters is limited to gammaproteobacteria.
Promoter-target gene evolutionary conservation


Evidence    

 [IMP] Inferred from mutant phenotype

 [BPP] Binding of purified proteins

 [GEA] Gene expression analysis



Reference(s)    

 [1] Dell CL., Neely MN., Olson ER., 1994, Altered pH and lysine signalling mutants of cadC, a gene encoding a membrane-bound transcriptional activator of the Escherichia coli cadBA operon., Mol Microbiol 14(1):7-16

 [2] Tetsch L., Koller C., Haneburger I., Jung K., 2008, The membrane-integrated transcriptional activator CadC of Escherichia coli senses lysine indirectly via the interaction with the lysine permease LysP., Mol Microbiol 67(3):570-83

 [3] Watson N., Dunyak DS., Rosey EL., Slonczewski JL., Olson ER., 1992, Identification of elements involved in transcriptional regulation of the Escherichia coli cad operon by external pH., J Bacteriol 174(2):530-40

 [4] Brameyer S., Rosch TC., El Andari J., Hoyer E., Schwarz J., Graumann PL., Jung K., 2019, DNA-binding directs the localization of a membrane-integrated receptor of the ToxR family., Commun Biol 2:4

 [5] Kuper C., Jung K., 2005, CadC-mediated activation of the cadBA promoter in Escherichia coli., J Mol Microbiol Biotechnol 10(1):26-39



RegulonDB