Transcription factor that may regulate cell proliferation, migration and apoptosis. Involved in neural development and myogenesis. Transcriptional activator of MITF, acting synergistically with SOX10 (By similarity). Can bind to DNA as homodimer or a heterodimer with PAX7. Interacts with DAXX. Interacts with PAXBP1; the interaction links PAX3 to a WDR5-containing histone methyltransferase complex. Interacts with TBX18. Interacts with SOX10 (By similarity). Expressed during early neurogenesis. The Splotch (Sp) mouse mutant displays defects in neural tube closure in the form of exencephaly and spina bifida. The splotch-delayed (Spd) phenotype is less severe than the other Sp alleles. Belongs to the paired homeobox family.