Screening Assay for Insecticides

A method for identifying an insecticidal active compound that reduces the activity of a G-protein coupled receptor (GPCR) with the activity of an octopamine receptor, which method comprises:

• a) assembling in a membrane a polypeptide with the activity of an octopamine receptor which is originally not present in said membrane;
• b) applying at one side of the membrane a compound suspected of having the ability to inhibit the activity of said polypeptide which is originally not present said membrane;
• c) determining the activity of said polypeptide;
• and
• d) identifying the compound applied in (b) that reduces the activity of said polypeptide as an insect-controlling compound,
• wherein the polypeptide has the activity of an octopamine receptor selected from the group consisting of oa2, Oamb, Oct-beta-2R and Oct-beta-3R, and such receptor is from a species selected from the group consisting of Drosophila melanogaster, Myzus persicae, and Tribolium castaneum.

A nucleic acid molecule selected from the group consisting of:

• a) a nucleic acid molecule encoding the polypeptide shown in 2, 6, 10, 14, 18, 22, 26, 30, 34,
• b) a nucleic acid molecule shown in SEQ ID NO:
• 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169 or 173;
• c) a nucleic acid molecule, which, as a result of the degeneracy of the genetic code, can be derived from a polypeptide sequence according to SEQ ID NO:
• 130, 134, 138, 142, 146, 150, 154, 158, 162, 166, 170 or 174;
• d) a nucleic acid molecule having at least 50% identity with the nucleic acid molecule of b);
• e) a nucleic acid molecule encoding a polypeptide having at least 50% identity with the amino acid sequence of the polypeptide encoded by the nucleic acid molecule of (a) to (c);
• f) a nucleic acid molecule which hybridizes with a nucleic acid molecule of (a) to (c) under stringent hybridization conditions;
• g) a nucleic acid molecule encoding a polypeptide which can be isolated with the aid of monoclonal or polyclonal antibodies made against a polypeptide encoded by one of the nucleic acid molecules of (a) to (e) and having the activity of an octopamine G-protein coupled receptor (GPCR) and the receptor is selected from the group consisting of oa2, Oamb, Oct-beta-2R and Oct-beta-3R, and such receptor is from a species selected from the group consisting of Drosophila melanogaster, Myzus persicae, and Tribolium castaneum;
• h) a nucleic acid molecule encoding a polypeptide comprising the consensus sequence as shown in SEQ ID NO:
• 177, 178 or 179, or one or more motifs selected from the group consisting of SEQ ID NO:
• 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225 and 226;
• i) nucleic acid molecule which comprises a polynucleotide, which is obtained by amplifying a cDNA library or a genomic library using the primers selected from the group consisting of SEQ ID NO:
• 131, 132;
• 135, 136;
• 139, 140;
• 143, 144;
• 147, 148;
• 151, 152;
• 155, 156;
• 159, 160;
• 163, 164;
• 167, 168;
• 171, 172, 175, and 176;
• and
• j) a nucleic acid molecule which is obtainable by screening a suitable nucleic acid library under stringent hybridization conditions with a probe comprising a complementary sequence of a nucleic acid molecule of (a) or (b) or with a fragment thereof, having at least 200 nucleotides of a nucleic acid molecule complementary to a nucleic acid molecule sequence characterized in (a) to (e).