Probable ligand-activated transcriptional activator. Acts as a transcriptional regulator in GABAergic motor neuron cell fate specification and development. Promotes cell-type-specific expression of guanylate cyclase genes that have key roles in aggregation behavior and hyperoxia avoidance. Has no role in carbon dioxide avoidance. Interacts with daf-21/hsp90. Interacts with aha-1. Expressed in many distinct neuronal cells including RMED, RMEV, RMEL and RMER. Functions in URX neurons to promote aggregation behavior. Expressed during embryonic and larval development. Defects in neuronal differentiation, axon branching, aberrant cell migration and abnormal aggregation behavior on lawns of bacterial food.