Probable transcription factor that binds a motif with the core sequence 5'-C[ACT][TG]G-3'. Expressed in embryos, larvae and adults. RNAi-mediated knockdown results in defective cuticle development (PubMed:12888489). RNAi-mediated knockdown in L4 stage larvae has no effect, but upon reaching adulthood, over 95% of the embryos produced by these animals arrest and fail to hatch (PubMed:12888489). Development arrests at the three-fold stage, showing abnormal constrictions or puckering in the external cuticle and approximately 8% of embryos exhibit ruptures in their cuticles resulting in the extrusion of cells (PubMed:12888489). Belongs to the grh/CP2 family. Grainyhead subfamily.