Transcription factor that is required for cell fate of coelomocytes which are non-muscle mesodermal cells (PubMed:20335356). Acts in concert with, and by activating expression of, the homeodomain gene ceh-34 (PubMed:20335356). Binds to the sequence motif 5'-ATAAA[T/C]A-3' (PubMed:20335356). Expression begins during embryogenesis and persists in a small number of cells throughout larval development (at protein level) (PubMed:20335356). Expressed transiently in the postembryonic non-gonadal mesoderm (M lineage), first detected in M.dlp and M.drp as they begin to divide (PubMed:20335356). Embryonic lethality; those few animals that survive to adulthood lack functional embryonic and M lineage (mesoblast-cell) derived coelomocytes (CCs) (PubMed:20335356). RNAi-mediated knockdown abolishes expression of ceh-34 in the M lineage (PubMed:20335356).