Enables DNA-binding transcription activator activity, RNA polymerase II-specific and sequence-specific DNA binding activity. Involved in positive regulation of transcription by RNA polymerase II. Acts upstream of or within neuromuscular synaptic transmission; peripheral nervous system development; and regulation of T cell differentiation. Predicted to be located in nucleoplasm. Is expressed in genitourinary system; limb mesenchyme; limb musculature; tooth; and vibrissa. Orthologous to human EGR3 (early growth response 3). [provided by Alliance of Genome Resources, Apr 2022]