a general model that accounts for dmpk oligomerization, processing, and regulation has been proposed. in this model, transient activation of kinase activity would occur in response to g protein second messengers, while longterm activation of dmpk could be mediated by a membrane associated protease that cleaves dmpk-1 to release cytosolic dmpk-2 in a persistently activated form. the persistent activation of serine/threonine kinases has been shown to play a role in the determination of cell fate as well as memory production in the nervous system. in this respect, dmpk may be similar to pka and pkc, two kinases that can be transiently activated in response to second messengers or persistently activated by proteolytic removal of an autoinhibitory domain. thus, this model suggests that the two endogenous dmpk forms may possess different activities, localizations, regulators, and substrates and perform distinct physiological functions.