α complementation in the Cre recombinase enzyme

Abstract

The Cre-loxP system is increasingly exploited for spatial and temporal gene inactivation. Here we present a novel approach to achieve this goal of selective gene inactivation. Following the model of α complementation in the β-galactosidase enzyme, where the enzyme is split into independent polypeptides which are able to associate and maintain the enzymatic activity, we divided the Cre recombinase into two independent polypeptides (one containing the NH2 terminus (α) and a second one containing the COOH-terminus (α)). Individually, the two polypeptides have no detectable activity. However, when coexpressed the polypeptides are able to associate, giving rise to Cre enzymatic activity, which op..