Fig. 1: Endogenous lin-39::zf1::gfp expression pattern and conditional lin-39 depletion.

(A) Expression pattern of the endogenous zh120(lin-39::zf1::gfp) reporter at different stages of vulval development (see Supplementary Movie S1). Mid-sagittal DIC images overlaid with LIN-39::ZF1::GFP (green), with the separate GFP channel below. Animals were between the Pn.p (early L3) and the “Christmas tree” (L4.4) stage³² after the completion of the vulval cell divisions. The 1° and 2° vulval cells are indicated with arrowheads or lines. Arrowheads in the L4.4 animal indicate the VulA cells where LIN-39::ZF1::GFP expression persisted until late L4. At least 20 animals were examined for each of the stages shown. (B) Conditional lin-39 depletion. Left: Control lin-39(zh120); swIs79[ajm-1::gfp] L4 larva not carrying the [hs-16p::zif-1] array but subjected to a heat-shock in late L2 and grown on control RNAi plates. Right: lin-39(zh120); swIs79[ajm-1::gfp]; zh616[hs-16p::zif-1] L4 larvae subjected to an L2 heat shock and grown on lin-39 dsRNA bacteria, as illustrated in Supplementary Fig. 1B. Mid-sagittal DIC images overlaid with the LIN-39::ZF1::GFP and AJM-1::GFP (green), with the separate GFP channel below. VPC nuclei in the DIC images are marked by asterisks, VulA cells and cell junctions with yellow arrowheads (see Supplementary Fig. 1C for individual z-sections). The corresponding cell lineages are indicated underneath. (C) Quantification of vulval cell proliferation after conditional lin-39 depletion. All conditions included an L2 heat shock. Bars show the average cell numbers, error bars the standard deviations, and dots the individual values for the four indicated conditions. Two independent [hs-16p::zif-1] arrays (zhEx 616.1&616.2) were used. The numbers of animals scored are indicated in brackets. Statistical significance was determined with a Kruskal-Wallis non-parametric test followed by Dunn’s multiple comparison correction and is indicated with **** for p = 1e-11 and * for p < 0.0382. Scale bars are 20 µm. Source data are provided as a Source Data file.