Regulation of human FcepsilonRI beta chain gene expression by Oct-1.

The beta chain, a component of the high-affinity receptor for IgE (FcepsilonRI), plays an important role in IgE-mediated allergic reaction. The beta chain accelerates the function of FcepsilonRI by amplification of its surface expression and of signal transduction in effector cells such as mast cells and basophils. Two regulatory regions, +60/+66 and +70/+76, for the human beta chain gene that are required for the cell-type-specific transcriptional activation were identified by transient reporter assay. Electrophoretic mobility shift assay demonstrated that Oct-1 binds both the regions, among which the +70/+76 Oct-1 motif was critical for the transactivation of the beta promoter responsive to Oct-1 overexpression. Regulation of beta chain gene expression is discussed.