Brain Sensory Organs of the Ascidian : Structure, Function and Developmental Mechanisms.

During evolution, new characters are designed by modifying pre-existing structures already present in ancient organisms. In this perspective, the Central Nervous System (CNS) of ascidian larva offers a good opportunity to analyze a complex phenomenon with a simplified approach. As sister group of vertebrates, ascidian tadpole larva exhibits a dorsal CNS, made up of only about 330 cells distributed into the anterior sensory brain vesicle (BV), connected to the motor ganglion (MG) and a caudal nerve cord (CNC) in the tail.

, a New Marker for the Nervous System of the Tunicate .

Establishment of presynaptic mechanisms by proteins that regulate neurotransmitter release in the presynaptic is considered a fundamental step in animal evolution. Rab3 interacting molecule-binding proteins (Rimbps) are crucial components of the presynaptic and key players in calcium homeostasis. Although involvement in these dynamics has been described in distantly related models such as fly and human, the role of this family in most invertebrates remains obscure.