Rok

• Description: repressor of comK, nucleoid associated protein that serves to help repress expression of A+T-rich genes, many of which appear to have been acquired by horizontal gene transfer
  
  

Gene name	rok
Synonyms	ykuW
Essential	no
Product	transcriptional repressor
Function	regulation of genetic competence
MW, pI	21 kDa, 9.701
Gene length, protein length	573 bp, 191 aa
Immediate neighbours	ykuV, yknT
Get the DNA and protein sequences (Barbe et al., 2009)
Genetic context This image was kindly provided by SubtiList

The gene

Basic information

• Locus tag: BSU14240

Phenotypes of a mutant

higher excision rate of the conjugative transposon ICEBs1 PubMed

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: binds to extended regions of the B. subtilis genome that are characterized by a high A+T content and are known or believed to have been acquired by horizontal gene transfer PubMed

• Protein family:

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions:

• Localization:

Database entries

• Structure:

• UniProt: O34857

• KEGG entry: [3]

• E.C. number:

Expression and regulation

• Operon: rok PubMed

• Sigma factor:

• Regulation:
  • repressed under conditions that trigger sporulation (Spo0A) PubMed
  • repressed by SinR PubMed
  • repressed by Rok PubMed
  • repressed during logrithmic growth (AbrB) PubMed

• Regulatory mechanism:
  • Spo0A: transcription repression PubMed
  • SinR: transcription repression PubMed
  • Rok: transcription repression PubMed
  • AbrB: transcription repression PubMed

• Additional information:

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:

• GFP fusion:

• two-hybrid system:

• Antibody:

References

Reviews

Daniel Schultz, Peter G Wolynes, Eshel Ben Jacob, José N Onuchic
Deciding fate in adverse times: sporulation and competence in Bacillus subtilis.
Proc Natl Acad Sci U S A: 2009, 106(50);21027-34
[PubMed:19995980] [WorldCat.org] [DOI] (I p)

Original Publications

Wiep Klaas Smits, Alan D Grossman
The transcriptional regulator Rok binds A+T-rich DNA and is involved in repression of a mobile genetic element in Bacillus subtilis.
PLoS Genet: 2010, 6(11);e1001207
[PubMed:21085634] [WorldCat.org] [DOI] (I e)

Wiep Klaas Smits, Tran Thu Hoa, Leendert W Hamoen, Oscar P Kuipers, David Dubnau
Antirepression as a second mechanism of transcriptional activation by a minor groove binding protein.
Mol Microbiol: 2007, 64(2);368-81
[PubMed:17493123] [WorldCat.org] [DOI] (P p)

Hédia Maamar, David Dubnau
Bistability in the Bacillus subtilis K-state (competence) system requires a positive feedback loop.
Mol Microbiol: 2005, 56(3);615-24
[PubMed:15819619] [WorldCat.org] [DOI] (P p)

Mark Albano, Wiep Klaas Smits, Linh T Y Ho, Barbara Kraigher, Ines Mandic-Mulec, Oscar P Kuipers, David Dubnau
The Rok protein of Bacillus subtilis represses genes for cell surface and extracellular functions.
J Bacteriol: 2005, 187(6);2010-9
[PubMed:15743949] [WorldCat.org] [DOI] (P p)

Virginie Molle, Masaya Fujita, Shane T Jensen, Patrick Eichenberger, José E González-Pastor, Jun S Liu, Richard Losick
The Spo0A regulon of Bacillus subtilis.
Mol Microbiol: 2003, 50(5);1683-701
[PubMed:14651647] [WorldCat.org] [DOI] (P p)

Noel Baichoo, Tao Wang, Rick Ye, John D Helmann
Global analysis of the Bacillus subtilis Fur regulon and the iron starvation stimulon.
Mol Microbiol: 2002, 45(6);1613-29
[PubMed:12354229] [WorldCat.org] [DOI] (P p)

Tran Thu Hoa, Pablo Tortosa, Mark Albano, David Dubnau
Rok (YkuW) regulates genetic competence in Bacillus subtilis by directly repressing comK.
Mol Microbiol: 2002, 43(1);15-26
[PubMed:11849533] [WorldCat.org] [DOI] (P p)