Transcription factor which plays a role in hair follicle differentiation. Regulates FOXQ1 expression and that of other hair-specific genes. Expressed in differentiating keratinocytes. In the hair follicle lower matrix, expressed in all 3 hair shaft-forming compartments, i.e. cuticle, cortex and medulla. Expression stops sharply at the boundary with the germinal matrix compartment. Belongs to the Abd-B homeobox family.