| DISC 1 has also been shown to interact with a number of proteins with neurobiological pedigrees , including Ndel 1 ( NUDEL ) , a key regulator of neuronal migration with endo oligopeptidase activity , and PDE4B , a phosphodiesterase that is critical for cyclic adenosine monophosphate signaling and that is directly linked to learning , memory , and mood . ^^^ |