Studies of learning in marine invertebrates have yielded new information, implicating protein kinase C and calmodulin‐dependent protein kinase as critical components in pathways for learning and memory that are shared with higher vertebrates. Recent advances correlating in vitro biochemical and biophysical measurements with in vivo learning have begun to elaborate the roles in memory storage for these two kinases, their substrates, and signaling proteins such as calexcitin and calmodulin. Other studies have implicated transcription factors associated with kinases such as the (...) cyclic AMP response element binding protein (CREB). These experiments have resulted in a greater understanding of the role of second messengers, principally calcium and cyclic AMP (cAMP), as vehicles for transforming memory‐specific effects occurring at the membrane into permanent DNA‐mediated cellular and structural changes. (shrink)

Changes in several distinct types of neuronal proteins are now known to be associated with learning. In this review, we will summarize the properties of these proteins and relate these properties to prominent theories of the biochemical basis of memory.