pdDronpa1.2 is a photodissociable protein that can be reversibly switched between a green fluorescent dimeric state and a non-fluorescent monomeric state: exposure to light of 500nm quenches the fluorescence and dissociates the dimeric form to a monomeric state, while irradiation at 400nm restores the dimeric state and fluorescence. pdDronpa1.2 was derived by mutagenesis from Dronpa, containing the additional mutations M40I, V60A, D121R, V123T, K145N and N158I (PMID:28232577).