Enables DNA-binding transcription factor activity, RNA polymerase II-specific and RNA polymerase II cis-regulatory region sequence-specific DNA binding activity. Involved in several processes, including animal organ development; circulatory system development; and positive regulation of cell differentiation. Acts upstream of or within several processes, including animal organ development; epithelial cell differentiation; and regulation of transcription by RNA polymerase II. Located in cytoplasm and nucleus. Is expressed in several structures, including alimentary system; branchial arch; cardiovascular system; central nervous system; and eye. Used to study dilated cardiomyopathy and obesity. Orthologous to human PROX1 (prospero homeobox 1). [provided by Alliance of Genome Resources, Apr 2022]