THE ROLE OF GLWAMIDES IN METAMORPHOSIS OF HYDRACTINIA-ECHINATA

The metamorphosis of many marine invertebrate larvae is induced by env ironmental signals. Upon reception of the cues, internal signals have to be set in motion to convey information to all cells of the larvae. For hydrozoan larvae it was hypothesised that ectodermal neurosensory cells at the anterior part are those cells receptive of the inducer. R ecently, it was shown that novel peptides with a common GLWamide termi nus are found in Cnidaria. These peptides are located in a specific su bset of the anterior sensory cells. It was hypothesised that the neuro peptides represent an internal signal coordinating the metamorphic pro cess. In the current study we present further evidence for this hypoth esis. Induction of metamorphosis is very specific for the GLWamide ter minus and amidation is essential. The potency to metamorphose is stron gly correlated with the presence of GLWamide-immunoreactive cell bodie s. Our data fit our hypothesis about a very important role of GLWamide s in the initiation of the morphogenetic processes very well.