Predicted to enable DNA-binding transcription repressor activity, RNA polymerase II-specific and RNA polymerase II transcription regulatory region sequence-specific DNA binding activity. Predicted to be involved in negative regulation of transcription by RNA polymerase II and regulation of cell cycle. Predicted to act upstream of or within labyrinthine layer blood vessel development; labyrinthine layer morphogenesis; and regulation of transcription by RNA polymerase II. Predicted to be located in cytoplasm and nuclear speck. Orthologous to human ESX1 (ESX homeobox 1). [provided by Alliance of Genome Resources, Apr 2022]