Reducing the Dscam1 diversity affects fly viability and locomotion ability.

See also S2 and S3 Figs. (A-C) Survival rates at each development stage in the wild-type and mutants with reduced numbers of exon 4 (A), exon 6 (B), or exon 9 (C). The number of remaining variable exons is shown on the right. (D) Survival rates plotted against the remaining numbers of variable exon 4s, exon 6s, and exon 9s. Survival rates positively correlated with the number of variable exons, and the best-fitting Hill function corresponds to a sigmoidal curve. The Hill coefficient (h) is the sensitivity parameter. The dotted lines represent the spectra of phenotypic variations, i.e., the variation range of phenotype defects among different mutants with the same degree of Dscam1 diversity. The minimum phenotypic defects are shown by the upper dashed line, and the lower dashed line shows the maximum phenotypic defects. (E) Survival rates as a function of the number of ectodomain isoforms. The survival phenotype was more sensitive to exon 9 numbers (lower h) than to exon 4 and 6 numbers. (F) Locomotion ability of the fly adults correlated with the number of variable exons 6 and 9. Reducing to a single exon 4 did not affect the climbing ability of flies. (G) Locomotion ability of fly adults as a function of the number of the ectodomain isoforms. Data used to generate graphs can be found in S1 Data. Dscam1, Down syndrome cell adhesion molecule 1; WT, wild type.