Figure 2.

dsf behavioral phenotypes. The genotypes examined are (genotype 1) wild type (+/+), (genotype 2) dsf/+, (genotype 3) Df/+, (genotype 4) dsf/dsf, and (genotype 5) dsf/Df. (A) dsf females resist male courtship. Individual aged virgin females of the genotypes shown were paired with wild-type (Canton-S) males, and the time from the initiation of singing to copulation was measured. +/+, n = 30; dsf/+, n = 14; Df/+, n = 9; dsf/dsf, n = 19; and dsf/Df, n = 18. Mutants are significantly different from wild type (dsf/dsf, P < 0.0001; dsf/Df, P < 0.0001). (B and C) dsf females resist during copulation, as judged by excess movement during copulation. (B) The number of times the mating pair made a 180° turn was determined from the videotapes. +/+, n = 15; dsf/dsf, n = 11, P = 0.0037; and dsf/Df, n = 14, P = 0.0004. (C) The number of times the mating pair crossed a predetermined center line of the chamber was scored from the same videotapes as in B. +/+, n = 15; dsf/dsf, n = 11, P = 0.0009; and dsf/Df, n = 14, P = 0.0072. (D) Three homozygous dsf males forming a short courtship chain, including a copulation attempt by the middle male. Both homozygous dsf and dsf/deletion males demonstrate this phenotype but with incomplete penetrance. dsf males spend a substantial amount of time orienting and following other males, but dsf chains contain few individuals and are not continued over extended periods of time, probably due to the robust rejection response exhibited by dsf males. dsf males court wild-type males, but are not themselves courted by wild-type males. (E) dsf males are delayed in copulation. Single males of the genotypes shown were paired with aged wild-type (Canton-S) virgin females. The time from initiation of courtship to copulation was measured. +/+, n = 30; dsf/+, n = 13; Df/+, n = 10; dsf/dsf, n = 13, P < 0.0001; and dsf/Df, n = 17, P = 0.0003. (F) Abdominal curling is altered in dsf males. Courtship events involving males of the genotypes shown, and wild-type (Canton-S) females were recorded on videotape. The magnitude of abdominal bending for each observable bend was determined from the videotaped images, with ≤45° being the minimal bend observable and 180° being the maximum magnitude bend observable. Bending at 180° is necessary to achieve the genital–genital contact associated with copulation. Intermediate bending categories (data not shown) have generally intermediate percentages of total bends.