Figure 4.

Mutation of cato results in duplicated v'ch1 neurons. (A) Schematic of cato genomic region showing the location of the P-element and excision deletions. (B-E) Expression of Cato protein (green) is absent or strongly reduced in cato mutant embryos (Ase expression shown in magenta) (B, B') Heterozygous cato⁵¹³/CyO embryo. (C, C') Homozygous cato⁵¹³/cato⁵¹³ embryo. (D, D') Heterozygous cato⁵³⁶/CyO embryo. (E, E') Homozygous cato⁵³⁶/cato⁵³⁶ embryo. (F-K) Late stage embryos stained with 22C10 (green) for sensory neurons and anti-Cpo (magenta) for nuclei of neurons and support cells. Cells of the v'ch1 chordotonal organ are indicated: n = duplicated v'ch1 neurons; sc = unduplicated scolopale cells; ca = unduplicated cap cells. (F) Heterozygous cato⁵³⁶/CyO embryo, showing wild-type 22C10 pattern. (G, H) Homozygous cato⁵³⁶/cato⁵³⁶ embryos, showing duplicated v'ch1 neurons (n1, n2). In (H) several confocal sections are shown. (I) Hemizygous cato⁵¹³/Df(2L)Jp7 embryo, showing duplicated v'ch1 neurons. (J) Homozygous dap⁴/dap⁴ embryo stained with 22C10, showing duplicated v'ch1 neurons. Selected other neurons are labelled, and show no obvious duplication. (K) Double homozygous dap⁴cato⁵³⁶/dap⁴cato⁵³⁶ embryos stained with 22C10, showing similar phenotype to each single mutant in which v'ch neurons are duplicated but not adjacent neurons. (L) Schematic summary of the proposed neuronal duplication phenotype.