Partial loss-of-function alleles of dlp and dally were used in ethanol behavioral assays because they were less afflicted with the developmental defects and lethality caused by strong loss-of-function alleles. Stocks containing partial loss-of-function alleles, either dlpf03537 or dallyMB950, were first outcrossed onto the Berlin genetic background to normalize the genetic background between experimental and control flies. Each allele contains a transposon inserted into the first intron (Figure 2, A and E). dlpf03537 was found to be weakly viable and sterile as a homozygote but without overt morphological or behavioral phenotypes. Transcript levels of dlp in fly heads were reduced by 40% in dlpf03537 heterozygotes (P = 0.0363, n = 3 replicates, two-sample t-test); dlpf03537 failed to complement dlp1 lethality, strong evidence that dlpf03537 is a dlp allele. dallyMB950 was found to be homozygous viable and fertile, and it also had no overt morphological or behavioral phenotypes. Heads of homozygous dallyMB950 flies were shown to have a 27% reduction in dally transcript (P = 0.0218, n = 5 replicates, two-sample t-test), but dallyMB950 complemented the sterility and wing vein morphology phenotypes
