Probable transcription factor (PubMed:7956818, PubMed:24885717). Required to specify the fates of hypodermal and neuron-associated support cells (PubMed:7956818). Functions during vulval development, playing a role in vulval precursor cell fate specification (PubMed:11063687, PubMed:24885717). Positively modulates expression of homeobox protein lin-39, perhaps by binding to regulatory regions of the lin-39 gene, acting in the vulval lineage (PubMed:24885717). Expressed in somatic gonads and germline precursors until the 50-cell stage. After the 100-cell stage, expression is seen in differentiating hypodermal and support cells (at protein level). Expressed throughout development from embryos to adults. RNAi-mediated knockdown results in embryonic lethality (PubMed:30921322). This is rescued by RNAi-mediated knockdown of rsd-6, and nrde-2 (PubMed:30921322). RNAi-mediated knockdown at the larval L1 stage causes a weak but significant decrease in expression of lin-39 (PubMed:24885717). Knockdown in mothers caused lower levels of lin-39 expression in the P blastomere of embryos (PubMed:24885717). Knockdown in L1 stage larvae, in a lin-39 mutant background, causes abnormal fusion of vulval precursor cells at larval stage L2 (PubMed:24885717).