Plasticity in protein-DNA recognition: lac repressor interacts with its natural operator 01 through alternative conformations of its DNA-binding domain.

ABSTRACT: The lac repressor-operator system is a model system for understanding protein-DNA interactions and allosteric mechanisms in gene regulation. Despite the wealth of biochemical data provided by extensive mutations of both repressor and operator, the specific recognition mechanism of the natural lac operators by lac repressor has remained elusive. Here we present the first high-resolution structure of a dimer of the DNA-binding domain of lac repressor bound to its natural operator 01. The global positioning of the dimer on the operator is dramatically asymmetric, which results in a different pattern of specific contacts between the two sites. Specific recognition is accomplished by a combination of elongation and twist by 48 degrees of the right lac subunit relative to the left one, significa

SUBMITTER: Kalodimos CG 

PROVIDER: S-EPMC126071 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature