Homeobox protein Nkx2.2 contains a homeobox domain and may be involved in the morphogenesis of the central nervous system. It is a transcription factor that plays a critical role in the control of cell fate specification and differentiation in many tissues. In the developing central nervous system, this developmentally important transcription factor functions as a transcriptional repressor that governs oligodendrocyte （OL） differentiation and myelin gene expression.