EFFECTS OF SINGLE P-ELEMENT INSERTIONS ON OLFACTORY BEHAVIOR IN DROSOPHILA-MELANOGASTER

Single P-element (P[lArB]) insertional mutagenesis of an isogenic stra in was used to identify autosomal loci affecting odor-guided behavior of Drosophila melanogaster. The avoidance response to benzaldehyde of 379 homozygous P[lArB] element-containing insert lines was evaluated q uantitatively. Fourteen smell impaired (smi) lines were identified in which P[lArB] element insertion caused different degrees of hyposmia i n one or both sexes. The smi loci map to different cytological locatio ns and probably are novel olfactory genes. Enhancer trap analysis of t he smi lines indicates that expression of at least 10 smi genes is con trolled by olfactory tissue-specific promoter/enhancer elements.