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. 1993 May 25;21(10):2363–2367. doi: 10.1093/nar/21.10.2363

DNA sequence determinants of LexA-induced DNA bending.

R Lloubès 1, C Lazdunski 1, M Granger-Schnarr 1, M Schnarr 1
PMCID: PMC309533  PMID: 8506133

Abstract

The LexA repressor from Escherichia coli induces DNA bending upon interaction with the two overlapping operators which regulate the transcription of the colicin A encoding gene caa. Both caa operators harbor T-tracts adjacent to their recognition motifs. These tracts have been suggested to be especially favorable for the promotion of LexA-induced DNA bending. Here we show that this is indeed the case, since disruption of the TTTT-tract adjacent to operator O1 by the replacement of the two central thymine bases by AA, GA or CG markedly reduces LexA-induced DNA bending. Simple A.T-richness in this position is thus not sufficient to promote full LexA-induced bending, albeit a TAAT sequence is always more efficient to promote bending than those sequences containing one or two C/G base pairs.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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