Xdtx1, a Xenopus Deltex homologue expressed in differentiating neurons and in photoreceptive organs

Abstract

We report the isolation of Xdtx1, a Xenopus homologue of the Drosophila Deltex gene. Starting from tailbud stage, Xdtx1 transcripts are detected in the olfactory bulbs, pineal complex and along the neural tube according to an antero-posterior gradient showing a gap at the midbrain-hindbrain boundary. At tadpole stage, Xdtx1 expression is activated in the differentiating retina, where it is also found in the neuronal fibres of the outer and inner plexiform layers, while its expression in the pineal complex becomes restricted to the photosensitive frontal organ. Differently from other vertebrate Deltex homologues, Xdtx1 is exclusively expressed in regions undergoing neuronal differentiation as shown by complementarity with X-Notch-1 expression.