In vertebrates, the genes encoding the class of transcription factors called homeobox genes are found in clusters named A, B, C, and D on four separate chromosomes. Expression of these proteins is spatially and temporally regulated during embryonic development. This gene is part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation. For example, the encoded protein represses the transcription of differentiation-specific genes during keratinocyte proliferation, but this repression is then overcome by differentiation signals. This gene is highly similar to the antennapedia (Antp) gene of Drosophila. (provided by RefSeq)
Homeobox A5 (HOXA5) mediates organogenesis and development of mammary glands, lungs, digestive tract and thyroid. It is essential for ovary homeostasis. Mutation in HOXA5 gene hampers organogenesis as it affects axial specification in the cervico-thoracic level. HOXA5 has been shown to play an important role in breast tumorigenesis. It also regulates hematopoiesis by interacting with pleiotrophin (PTN).
