Lac Repressor Binding to Synthetic DNAs of Defined Nucleotide Sequence

AUTOR(ES)

Riggs, A. D.

RESUMO

Binding of lac repressor to 20 synthetic DNAs of high molecular weight with defined repeating sequences was investigated by competition experiments. Although none of these DNAs binds repressor as tightly as does lac operator, most do bind to a measurable extent. Their affinity for repressor varies greatly and is a function of both nucleotide composition and sequence. Poly(dC-dC)·poly(dG-dC) competes for repressor 200-times less well than either poly(dA-dT)·poly(dA-dT) or poly(dT-dT-dG)·poly(dC-dA-dA). The other DNAs show a broad spectrum of affinities for repressor between these extremes. These results show that the lac repressor has affinity for, and can distinguish between, sequences distantly related to its operator.

Documentos Relacionados

• Studies of gene control regions. III. Binding of synthetic and modified synthetic lac operator DNAs to lactose repressor.
• Binding of E.coli lac repressor to non-operator DNA*
• Binding of synthetic lactose operator DNAs to lactose repressors*
• The Amino-Acid Sequence of lac Repressor
• lac repressor changes conformation upon binding to poly[dA-T)]