Regulation of synaptic function by neurotrophic factors in vertebrates andinvertebrates: Implications for development and learning

Recent studies have demonstrated that neurotrophic factors contribute to th e molecular events involved. in synaptic plasticity, both during vertebrate development and in the mature nervous system. Although it is well establis hed that many of the cellular and molecular mechanisms underlying synaptic plasticity are conserved between invertebrates and vertebrates, there are, as yet, very few neurotrophic factors identified in invertebrate species. N onetheless, vertebrate neurotrophins can influence invertebrate neuronal gr owth and plasticity. In addition, homologs of neurotrophic factor receptors have been identified. in several invertebrate species. These studies may i ndicate that the roles of neurotrophins in both developmental and. adult pl asticity are highly conserved across diverse phyla.