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Open Access

Promoter analysis by saturation mutagenesis

Biological Procedures Online3:31064

Received: 30 August 2001

Accepted: 17 December 2001


Gene expression and regulation are mediated by DNA sequences, in most instances, directly upstream to the coding sequences by recruiting transcription factors, regulators, and a RNA polymerase in a spatially defined fashion. Few nucleotides within a promoter make contact with the bound proteins. The minimal set of nucleotides that can recruit a protein factor is called a cis-acting element. This article addresses a powerful mutagenesis strategy that can be employed to define cis-acting elements at a molecular level. Technical details including primer design, saturation mutagenesis, construction of promoter libraries, phenotypic analysis, data analysis, and interpretation are discussed.

Indexing terms

promoter regions (genetics)mutagenesispolymerase chain reaction