Transcription factor AP-2 alpha: The TFAP2A gene provides instructions for making a protein called transcription factor AP-2 alpha (AP-2α).
The TFAP2A gene provides instructions for making a protein called transcription factor AP-2 alpha (AP-2α). As its name suggests, this protein is a transcription factor, which means it attaches (binds) to specific regions of DNA and helps control the activity of particular genes. Transcription factor AP-2α is one of a group of related proteins called AP-2 transcription factors. These proteins regulate genes that help control cell division and the self-destruction (apoptosis) of cells that are no longer needed.
Transcription factor AP-2α is involved in development before birth. In particular, this protein is active in the neural crest, which is a group of cells in the early embryo that give rise to many tissues and organs. Among the embryonic structures formed from neural crest cells are the branchial arches, which develop into the bones and other tissues of the head and neck. The TFAP2A gene appears to be especially important for the development of tissues derived from the first and second branchial arches.
Mutations in the TFAP2A gene cause a condition called branchio-oculo-facial syndrome, which is characterized by skin anomalies on the neck, malformations of the eyes and ears, and distinctive facial features. Most TFAP2A gene mutations involved in this condition change single protein building blocks (amino acids) in the transcription factor AP-2α protein. These changes tend to occur in a region of the protein that enables it to bind to DNA. Although the effect of the amino acid changes on transcription factor AP-2α is unknown, the protein's DNA binding function is likely impaired. Without this function, the protein cannot control the activity of genes during development. TFAP2A gene mutations disrupt the development of structures derived from the branchial arches, which results in the characteristic features of branchio-oculo-facial syndrome.