Paired box domain

Paired box (Pax) genes are a family of genes coding for tissue specific transcription factors containing a paired domain and usually a partial, or in the case of four family members (PAX3, PAX4, PAX6 and PAX7), a complete homeodomain. An octapeptide may also be present. Pax proteins are important in early animal development for the specification of specific tissues, as well as during epimorphic limb regeneration in animals capable of such.

Within the mammalian family, there are four well defined groups of Pax genes.

Orthologous genes exist throughout the Metazoa, including extensive study of the ectopic expression in Drosophila using murine Pax6.

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