The synapsins and the regulation of synaptic function

Synapsins I and II are a family of synaptic vesicle†associated phosphoproteins involved in the short†term regulation of neurotransmitter release. In this review, we discuss a working model for the molecular mechanisms by which the synapsins act. We propose that synapsin I links synaptic vesicles to actin filaments in the presynaptic nerve terminal and that these interactions are modulated by the reversible phosphorylation of synapsin I through various signal transduction pathways. The high degree of homology between the synapsins suggests that some of the functional properties of synapsin I are also shared by synapsin II. Copyright © 1990 Cambridge University Press