... to somatic motoneurons of the abducens nucleus. In r6, the absence of any combination of the Hox3 paralogous genes results in ectopic expression of the r4-specific determinant Hoxb1 . This ectopic expression in turn results in the differentiation of r4-like facial branchiomotoneurons within this rhombomere...

... and crustaceans, consistent with the proposed intermediate phylogenetic position of the Myriapoda. Second, we found two ‘extra’ Hox genes in the centipede compared with those in Drosophila . Based on its pattern of expression, Hox3 appears to have a typical Hox-like role in the centipede, suggesting...