Crucial role of zebrafish prox1 in hypothalamic catecholaminergic neurons development

Abstract

<p>Abstract</p> <p>Background</p> <p><it>Prox1</it>, the vertebrate homolog of <it>prospero </it>in <it>Drosophila melanogaster</it>, is a divergent homeogene that regulates cell proliferation, fate determination and differentiation during vertebrate embryonic development.</p> <p>Results</p> <p>Here we report that, in zebrafish, <it>prox1 </it>is widely expressed in several districts of the Central Nervous System (CNS). Specifically, we evidenced <it>prox1 </it>expression in a group of neurons, already positive for <it>otp1</it>, located in the hypothalamus at the level of the posterior tuberculum (PT). Prox1 knock-down determines the severe loss of hypothalamic catecholaminergic (CA) neurons, identified by tyrosine hydroxylase (TH) expression, and the synergistic <it>prox1/otp1 </it>overexpression induces the appearance of hypothalamic supernumerary TH-positive neurons and ectopic TH-positive cells on the yolk epitelium.</p> <p>Conclusion</p> <p>Our findings indicate that <it>prox1 </it>activity is crucial for the proper development of the <it>otp1</it>-positive hypothalamic neuronal precursors to their terminal CA phenotype.</p