Our research showed that the N-terminus of voltage-gated potassium channel subunits controls the assembly of these proteins into a functional channel. Recently, we have used this fact to regulate potassium channel expression in neurons in a light dependent manner. Structural modeling was used to insert a LOV domain next to the T1 domain to create Opto-Kv channels. LOV domains change their structure following absorption of blue wavelength photons. Using the design we developed, we could demonstrate light dependent regulation of voltage-gated potassium channel formation. In addition, we showed that insertion of a dominant negative pore mutation into these constructs results in a subunit (Opto-Kv(DN)) that knocks down wild type channel expression in a light dependent manner. Recently, we have found that these constructs can be used to regulate animal behavior.