RpoB

• Description: RNA polymerase beta subunit
  
  

Gene name	rpoB
Synonyms
Essential	yes PubMed
Product	RNA polymerase beta subunit
Function	transcription
Gene expression levels in SubtiExpress: rpoB
Interactions involving this protein in SubtInteract: RpoB
MW, pI	133 kDa, 4.731
Gene length, protein length	3579 bp, 1193 aa
Immediate neighbours	ybxB, rpoC
Sequences	Protein DNA DNA_with_flanks
Genetic context This image was kindly provided by SubtiList
Expression at a glance   PubMed

Categories containing this gene/protein

transcription, essential genes, membrane proteins, phosphoproteins

This gene is a member of the following regulons

stringent response

The gene

Basic information

• Locus tag: BSU01070

Phenotypes of a mutant

essential PubMed

Database entries

• BsubCyc: BSU01070

• DBTBS entry: [1]

• SubtiList entry: [2]

Additional information

• A mutation was found in this gene after evolution under relaxed selection for sporulation PubMed
• mutations in mtrB, sigB, rpoB, and rpoC allow B. subtilis to grow with 4-fluorotryptophan rather than with tryptophan as a canonical amino acid of the genetic code PubMed

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: Nucleoside triphosphate + RNA(n) = diphosphate + RNA(n+1) (according to Swiss-Prot)

• Protein family: RNA polymerase beta chain family (according to Swiss-Prot)

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:
  • phosphorylated on (Arg-312 OR Arg-313), Arg-539, (Arg-693 OR Arg-694), Arg-827, and Arg-1106 PubMed

• Cofactors:

• Effectors of protein activity:

• Interactions:
  • RpoA-RpoB-RpoC PubMed, NusA-RpoB PubMed
  • SigA-(RpoB-RpoC) PubMed, SigB-(RpoB-RpoC)
  • SigD-(RpoB-RpoC), SigE-(RpoB-RpoC)
  • SigF-(RpoB-RpoC), SigG-(RpoB-RpoC)
  • SigH-(RpoB-RpoC), SigI-(RpoB-RpoC)
  • SigK-(RpoB-RpoC), SigL-(RpoB-RpoC)
  • SigM-(RpoB-RpoC), SigV-(RpoB-RpoC)
  • SigW-(RpoB-RpoC), SigX-(RpoB-RpoC)
  • SigY-(RpoB-RpoC), SigZ-(RpoB-RpoC)
  • Xpf-(RpoB-RpoC), YlaC-(RpoB-RpoC)
  • YvrI-RpoB PubMed,
  • Mfd-RpoB PubMed
  • RpoB-RpoE (demonstrated for S. aureus) PubMed

• Localization: membrane associated PubMed

Database entries

• BsubCyc: BSU01070

• Structure:
  • 3MLQ (RNA polymerase interacting domain of Thermus thermophilus Mfd with the Thermus aquaticus RpoB beta1 domain) PubMed

• UniProt: P37870

• KEGG entry: [3]

• E.C. number: 2.7.7.6

Additional information

• subject to Clp-dependent proteolysis upon glucose starvation PubMed

Expression and regulation

• Operon: rpoB-rpoC PubMed

• Expression browser: rpoB PubMed

• Sigma factor: SigA PubMed

• Regulation:
  • RelA dependent downregulation (Class I) during stringent response PubMed

• Regulatory mechanism:

• Additional information:
  • subject to Clp-dependent proteolysis upon glucose starvation PubMed
  • The mRNA has a long 5' leader region. This may indicate RNA-based regulation PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 3434 PubMed
  • number of protein molecules per cell (complex medium with amino acids, without glucose): 10168 PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium, exponential phase): 1411 PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium, early stationary phase after glucose exhaustion): 800 PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium, late stationary phase after glucose exhaustion): 802 PubMed

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:
  • GP2047 (aphA3) based on pAC7, available in Jörg Stülke's lab
  • GP2052 (cat) based on pAC5, available in Jörg Stülke's lab

• GFP fusion:

• two-hybrid system: B. pertussis adenylate cyclase-based bacterial two hybrid system (BACTH), available in Fabian Commichau's lab

• FLAG-tag construct:
  • GP2043 rpoB-3xFLAG ermC (based on pGP1087), available in Jörg Stülke's lab

• Antibody:

References

Reviews

Nikolay Zenkin
Multiple personalities of the RNA polymerase active centre.
Microbiology (Reading): 2014, 160(Pt 7);1316-1320
[PubMed:24763425] [WorldCat.org] [DOI] (I p)

Lakshminarayan M Iyer, L Aravind
Insights from the architecture of the bacterial transcription apparatus.
J Struct Biol: 2012, 179(3);299-319
[PubMed:22210308] [WorldCat.org] [DOI] (I p)