The cyclic G dependent protein kinase gene is identified in both comparisons. This gene is widely and multifocally expressed in brain in cells including neurons [43]. Proper PRKG1 expression is important for proper brain development [44]. Variants in this gene can lead to marked differences in behaviors of drosophila [45]. Nitric oxide can dramatically modulate brain cGMP systems, suggesting that these systems may provide some of the primary targets for the products of nitric oxide synthases (NOS). Mnemonic and addictive functions can each be altered by changes in cGMP-dependent protein kinase and/or NOS [46-48].
