Enables RNA polymerase II transcription regulatory region sequence-specific DNA binding activity. Involved in negative regulation of transcription by RNA polymerase II. Predicted to be located in several cellular components, including growth cone; neuronal cell body; and nuclear body. Predicted to be part of ribonucleoprotein complex. Predicted to be active in cytoplasm and nucleus. Human ortholog(s) of this gene implicated in Charcot-Marie-Tooth disease axonal type 2S and distal spinal muscular atrophy 1. Orthologous to human IGHMBP2 (immunoglobulin mu DNA binding protein 2). [provided by Alliance of Genome Resources, Apr 2022]