Figure 3. UNC-86 is a master regulator of the HSN transcription factor combination.

(A) Expression of the HSN TFs in different mutant backgrounds. All scorings were performed at adult stages except for HLH-3, where early L4 larvae were scored. Embryonic HLH-3 expression is unaffected in unc-86 mutants (data not shown). Graphs show the percentage of TF expression in mutant animals relative to wild type expression. n > 100 cells per condition, Fisher's exact test, *: p-value<0.05, See Source data 1 for raw data and exact p-values. (B) Summary of relationships among the HSN TF combination, black arrows mean strong effect (more than 50% loss of expression) and grey arrows depicts the rest of significant defects. (C) Loss-of-function (RNAi) experiments after HSN differentiation show that AST-1, UNC-86, SEM-4, EGL-46 and EGL-18 are required to maintain proper tph-1::yfp and cat-1::MDM2::gfp (unstable GFP) reporter expression. Worms were also scored prior to RNAi treatment to confirm correct HSN differentiation before starting the experiment. n > 100 cells per condition, Fisher's exact test, *: p-value <0.05. See Source data 1 for raw data and Figure 3—figure supplement 1 for maintenance analysis with temperature-sensitive alleles.

Figure 3—figure supplement 1. AST-1, UNC-86 and SEM-4 are required to maintain the HSN differentiated state.

Three temperature-sensitive alleles ast-1(ot417), unc-86(n848) and sem-4(n2654) were used to perform temperature shifts to restrictive temperatures after HSN has fully differentiated (young adult). Temperature shifts (red lines) lead to reporter expression defects. Red asterisks refer to the comparison between mutant values before and after the temperature shift and blue asterisks refer to the comparison at the same time point between shifted animals (red line) and animals kept at permissive temperature (blue line) (n > 100 cells per condition). Fisher's exact test, *: p-value<0.05. Related to Figure 3.