Fig. 5.
Column-based flight assay used to measure the relative capacity of flies for flight. Flies are dropped from a vial into the center of an oil-coated cylinder. The falling flies fly from the center and are trapped in the oil. The distance that they fall is correlated with their capacity for flight (Benzer, 1973; Elkins et al., 1986; Green et al., 1986). The column was fractionated, top to bottom, into bins 5 cm in length. The abscissa represents the distance from the top of the column that the flies fell. The ordinate is the percentage of animals assayed. A, Theash218 chromosome was tested for its capacity to complement the flight defect associated with theslo4 mutant allele. Results from an assay performed using 952 w1118, 828slo4, and 733ash218/slo4transheterozygotes. B, Ability of theash218 chromosome to complement the flight defect associated with theslo1 mutant allele. Results from an assay performed using 1002 w1118, 903 w1118; st bar3slo1,and 369ash218/st bar3slo1 flies. Thew1118 stock carries a wild-type copy of the slowpoke gene and served at the positive control. Wild-type flies (squares) and theash218/slo4orash218/slo1transheterozygotes (triangles) accumulate near the top of the column. The slo4 orslo1 homozygotes (circles) accumulate deeper in the column. Flies that did not initiate flight are not counted and are trapped in a pool of oil at the bottom of the column.