Patent ID: 6972193

Claim:
A nucleic acid composition comprising at least two genetic constructs, each encoding a chimeric protein, (a) a first construct encoding a first chimeric protein comprising at least one ligand-binding domain and a transcriptional activation domain which is heterologous thereto, and, (b) a second construct encoding a second chimeric protein comprising at least one ligand-binding domain which may be the same or different from a ligand binding domain of the first chimeric protein, and a DNA binding domain which is heterologous thereto, wherein the first and second of said chimeric proteins together (i) bind to a ligand to form a ligand cross-linked protein complex, and (ii) in a ligand dependent manner, activate transcription of a gene having a transcriptional regulatory element to which the DNA binding domain binds, and wherein the ligand-binding domain of at least one of the chimeric proteins is an FKBP domain.