response while leaving short-term responses to a stimulus intact). Such 
agents might target one of the later elements in the signal transduction 
cascade between the stimulus and the CIE gene promoter. For instance, it 
has been shown that certain types of benzodiazepines can greatly augment 
the IE response, whereas calcium channel blockers and calmodulin antagonists 
suppress it (Curran and Morgan 1985; Morgan and Curran 1986; reviewed in 
Morgan and Curran 1 991 a, 1 991 b). Other agents might target the CIE gene 
product by, for example, impeding their binding to DNA or a partner protein or 
modifying posttranslational events (Curran and Morgan 1986). The use of 
transdominant suppressor molecules in transgenic mice might provide such 
an avenue. Until such issues are clarified, the precise role that the CIE genes 
fulfill and the utility of regulating their expression and function in vivo will remain 
an open question. 
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