Figure 4.—
Homozygous mutant adults live up to 3 weeks, but have decreased fertility. (A–C) Decreased life span of the adult dVMATP1 mutant, compared to the control w1118CS10 (indicated as “w−; +/+”). (A and B) Survival curves of the dVMATP1 homozygotes (P/P) are shown (4–5 replicates of 20 flies at 25°). A similar decrease in average life span is seen in A homozygous females (−24%, 5 internal replicates of 20 flies, Wilcoxon-rank test comparing the survival curves P < 0.023), and in B homozygous males (−31%, Wilcoxon-rank test P < 0.017). (C) Female dVMATP1 heterozygotes show a decrease in life span when tested at either 25° (−27% ± 8, three independent experiments with three to four internal replicates of 20–40 flies, Student's t-test comparing average life span to controls, *P < 0.024) or 29° (−27% ± 2, two to three independent experiments with four internal replicates of 40 flies, Student's t-test, ***P < 0.0001) as compared to the control line. Male heterozygous mutants do not show a decrease in life span at either 25° or 29°. (D and E) Decreased fertility in homozygous dVMAT mutants and mutants over deficiency and rescue by UAS-dVMAT-A cDNA. For each cross, individual flies of the indicated genotype were mated with two to three CS control flies (+/+) of the opposite sex for 5 days. Columns indicate the percentage of individual crosses yielding adult progeny. The number of individual crosses made is indicated in each column. (D) Homozygote female mutants are infertile: homozygous dVMATP1 females mated to CS males did not yield any progeny in 89 testcrosses. A few vials with progeny were seen using dVMATΔ14 homozygotes (D14) and mutants over deficiency (P/CX1, P/MK2, and D14/CX1). Fertility of the genetically rescued females (P/P; rescue/+) differed from all the mutant lines (P/P, D14, P/CX1, P/MK2, D14/CX1, one-way ANOVA P < 0.0001, Bonferroni post-test as indicated on the graph, ***P < 0.001). The fertility of the rescue line did not differ from controls. (E) Male dVMAT homozygotes show reduced fertility, with only ∼20% of the crosses for P/P or D14/D14 males to CS females yielding progeny. The fertility of genetically rescued males (dVMATP1/dVMATP1; da-GAL4, UAS-DVMAT-A/+, indicated as “P/P; rescue/+”) is significantly higher than all of the mutant lines including P/P, D14, P/CX1, P/MK2, D14/CX1, (Bonferroni post-test, ***P < 0.001) but does not differ from either CS controls, dVMAT heterozygotes, heterozygous deficiencies (CX1/+ and MK2/+), or CS flies expressing the rescue transgenes (da-GAL4, UAS-DVMAT-A/+ indicated as “rescue/+”).