SOS box

SOS box is the operator to which the LexA repressor binds to repress the transcription of SOS-induced proteins. SOS boxes are found near the promoter of various genes.^[1]

LexA binds to an SOS box in the absence of DNA damage. In the presence of DNA damage the binding of LexA is inactivated by the RecA activator. SOS boxes differ in DNA sequences and binding affinity towards LexA from organism to organism.^[2] Furthermore, SOS boxes may be present in a dual fashion, which indicates that more than one SOS box can be within the same promoter.^[3]

Examples

Phylogenetic Clade	Sequence	Reference
Alphaproteobacteria	GAAC(N)7GAAC GTTC(N)7GTTC	[4][5]
Betaproteobacteria Gammaproteobacteria	CTGT(N)8ACAG	[6]
Deltaproteobacteria	CTRHAMRYBYGTTCAGS	[7]
Gram-positive bacteria	CGAACRNRYGTTYC	[8][9]
Cyanobacteria	RGTAC(N)3DGTWCB	[10]

See Nucleic acid nomenclature for an explanation of non-GATC nucleotide letters.

See also

• SOS response

References

1. Henkin, Tina M.; Peters, Joseph E. (2020). Snyder and Champness molecular genetics of bacteria (Fifth ed.). Hoboken, NJ : Washington, D.C: John Wiley & Sons, Inc. p. 409. ISBN 9781555819750.
2. Walker, Graham C. (October 1995). "SOS-regulated proteins in translesion DNA synthesis and mutagenesis". Trends in Biochemical Sciences. 20 (10): 416–20. doi:10.1016/s0968-0004(00)89091-x. PMID 8533155.
3. Gillor, Osnat; Vriezen, Jan A. C.; Riley, Margaret A. (Jun 2008). "The role of SOS boxes in enteric bacteriocin regulation". Microbiology. 154 (6): 1783–1792. doi:10.1099/mic.0.2007/016139-0. PMC 2729051. PMID 18524933.
4. Fernández de Henestrosa, Antonio R.; Rivera, Eusebi; Tapias, Angels; Barbé, Jordi (June 1998). "Identification of the Rhodobacter sphaeroides SOS box". Molecular Microbiology. 28 (5): 991–1003. doi:10.1046/j.1365-2958.1998.00860.x. PMID 9663685.
5. Tapias, A.; Barbé, J. (August 1999). "Regulation of divergent transcription from the uvrA-ssb promoters in Sinorhizobium meliloti". Molecular and General Genetics MGG. 262 (1): 121–130. doi:10.1007/s004380051066. PMID 10503543. S2CID 2373618.
6. Erill, Ivan; Escribano, Marcos; Campoy, Susana; Barbé, Jordi (22 November 2003). "In silico analysis reveals substantial variability in the gene contents of the gamma proteobacteria LexA-regulon". Bioinformatics. 19 (17): 2225–2236. doi:10.1093/bioinformatics/btg303. PMID 14630651.
7. Campoy, Susana; Fontes, Marta; Padmanabhan, S.; Cortés, Pilar; Llagostera, Montserrat; Barbé, Jordi (August 2003). "LexA-independent DNA damage-mediated induction of gene expression in Myxococcus xanthus". Molecular Microbiology. 49 (3): 769–781. doi:10.1046/j.1365-2958.2003.03592.x. PMID 12864858.
8. Winterling, Kevin W.; Chafin, David; Hayes, Jeffery J.; Sun, Ji; Levine, Arthur S.; Yasbin, Ronald E.; Woodgate, Roger (15 April 1998). "The Bacillus subtilis DinR Binding Site: Redefinition of the Consensus Sequence". Journal of Bacteriology. 180 (8): 2201–2211. doi:10.1128/JB.180.8.2201-2211.1998. PMC 107149. PMID 9555905.
9. Davis, Elaine O.; Dullaghan, Edith M.; Rand, Lucinda (15 June 2002). "Definition of the Mycobacterial SOS Box and Use To Identify LexA-Regulated Genes in Mycobacterium tuberculosis". Journal of Bacteriology. 184 (12): 3287–3295. doi:10.1128/JB.184.12.3287-3295.2002. PMC 135081. PMID 12029045.
10. Mazón, G.; Lucena, J. M.; Campoy, S.; Fernández de Henestrosa, A. R.; Candau, P.; Barbé, J. (February 2004). "LexA-binding sequences in Gram-positive and cyanobacteria are closely related". Molecular Genetics and Genomics. 271 (1): 40–49. doi:10.1007/s00438-003-0952-x. PMID 14652736. S2CID 9219764.