lexA [2017-8-11 16:0:3]

transcriptional repressor of the SOS regulon

locus: BSU17850

pI: 5.16

mw: 22.70 kDa

protein length: 205 aa

gene length: 615 bp

function: regulation of DNA damage repair

product: transcriptional repressor of the SOS regulon

essential: no

synonyms: dinR

Genomic Context

categories

• [category|SW 3|Information processing] → [category|SW 3.1|Genetics] → [category|SW 3.1.5|DNA repair/ recombination]
• [category|SW 3|Information processing] → [category|SW 3.1|Genetics] → [category|SW 3.1.5|DNA repair/ recombination] → [category|SW 3.1.5.6|Other proteins]
• [category|SW 3|Information processing] → [category|SW 3.4|Regulation of gene expression] → [category|SW 3.4.2|Transcription factors and their control] → [category|SW 3.4.2.5|Transcription factors/ other]

Gene

Coordinates: 1,917,639 → 1,918,256

The protein

Catalyzed reaction/ biological activity

• Represses ''[gene|DEFBDC2AB8E43FB06C65389160E8EACFE5FB9705|uvrB], [gene|DEB7605B4F6F5F365A49C1C15647F9767B01BF66|bstG], [gene|60344F56DEB167FA62C16E52E8238393CEE19312|tagC], [gene|A44D4677FB70BE8F554BF1001A500F817C7DA95F|recA]'' genes and itself by binding to the 14 bp palindromic sequence 5'-CGAACNNNNGTTCG-3'. In the presence of single-stranded DNA, [protein|A44D4677FB70BE8F554BF1001A500F817C7DA95F|RecA] interacts with [protein|D267AF38B0CF107042326E9B8F3DD3C9C85840E4|LexA] causing an autocatalytic cleavage which disrupts the DNA-binding part of [protein|D267AF38B0CF107042326E9B8F3DD3C9C85840E4|LexA], leading to derepression of the SOS regulon and eventually DNA repair. (according to Swiss-Prot)

Protein family

• peptidase S24 family (according to Swiss-Prot)

Structure

• [PDB|1JHH] (from ''E. coli'', S119A mutant, 33% identity, 52% similarity) [Pubmed|11551506]

Expression and Regulation

Operons

• genes: [gene|D267AF38B0CF107042326E9B8F3DD3C9C85840E4|lexA]
  description: [Pubmed|1657879]

  regulatory mechanism

  • [protein|D267AF38B0CF107042326E9B8F3DD3C9C85840E4|LexA]: repression, [Pubmed|2548995], in [regulon|D267AF38B0CF107042326E9B8F3DD3C9C85840E4|LexA regulon]
  • [protein|BEE6F16D6A5BBC7FED9E8EB5FA6A94BBF932BBDA|RocR]: autorepression, in [regulon|BEE6F16D6A5BBC7FED9E8EB5FA6A94BBF932BBDA|RocR regulon]

  regulation

  • induced upon DNA damage ([protein|search|LexA]) [Pubmed|1657879,8899710,16267290]

  additional information

  • A [protein|search|ncRNA] is predicted between '[protein|search|fosB]' and '[protein|search|lexA]' [PubMed|20525796]

References

Reviews

• 22933559,18726173

Original publications

• 8899710,9045831,9555905,8969214,1657879,16267290,11551506,16549676,20525796