Transcriptional regulator with a possible role in patterning of mesoderm during development. Predominantly in neural crest-derived mesenchyme and in lateral plate mesoderm. Prominent expression in frontonasal head mesenchyme and in the first and second pharyngeal arches and some of their derivatives. High expression is also seen in the tail and in many derivatives of the lateral plate mesoderm including the limbs, the body wall, and the genital tubercle. Expressed in embryos from 8 days of gestation onward. Belongs to the paired homeobox family.