Patent ID: 8497093

Claim:
A method of modulating the expression of a gene in a host cell comprising the gene to be modulated, the method comprising: (a) introducing into the host cell a gene expression modulation system comprising (i) a first gene expression cassette comprising a polynucleotide sequence that encodes a first polypeptide comprising a leafhopper ecdysone receptor ligand binding domain, wherein said first polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 2, amino acids 1-5 of SEQ ID NO 2, amino acids 6-71 of SEQ ID NO: 2, amino acids 72-149 of SEQ ID NO: 2, amino acids 150-370 of SEQ ID NO: 2, acids 6-370 of SEQ ID NO: 2, amino acids 72-370 of SEQ ID NO: 2 and amino acids 140-370 of SEQ ID NO 2; and (ii) a second gene expression cassette comprising a polynucleotide sequence that encodes a second polypeptide comprising a nuclear receptor ligand binding domain; and (b) introducing into the host cell a ligand that binds to the leafhopper ecdysone receptor ligand binding domain, wherein one of the first gene expression cassette or the second gene expression cassette comprises a polynucleotide sequence encoding a DNA-binding domain that recognizes a response element associated with a gene of interest, wherein the first gene expression cassette or the second gene expression cassette that does not comprise a polynucleotide sequence encoding the DNA-binding domain comprises a polynucleotide sequence encoding a transactivation domain, wherein the ligand binding domain in the first polypeptide and the ligand binding domain in the second polypeptide are different and dimerize, and wherein the gene that is expressed is a component of a chimeric gene comprising: (i) a response element to which the DNA-binding domain binds; (ii) a promoter that is activated by the transactivation domain; and (iii) the gene that is expressed.