Many cephalopod species employ iridescence both as a means of camouflage and communication. In particular, members of the recently evolved Loliginid squid family display a mode of tunable iridescence that draws interest as a possible model for biologically inspired dynamically tunable photonic devices. This dynamic tunability is mediated by charge neutralization-induced secondary folding and hierarchical assembly of the intrinsically unstructured cationic reflectin proteins. Reflectins are found within the lamellae of specialized Bragg reflector cells, which tunably reflect light across the visible spectrum. In order to understand the mechanisms controlling the tunable assembly of the reflectins, we studied assembly of wild type and mutant recombinant Doryteuthis opalescens reflectin A1 as a function of pH using dynamic light scattering (DLS) and native tryptophan fluorescence. Additionally, we have begun investigations into liquid-liquid phase separation as an avenue to reflectin assembly in vivo. To better investigate and understand this mechanism, we used cryo-TEM and bright field microscopy to visualize reflectin assemblies under near physiological conditions. These experiments have revealed relationships between reflectin assembly and neutralization of protein net charge density, and screening of electrostatic interactions as drivers of secondary folding and hierarchical assembly. These results further elucidate the fundamental mechanisms of protein assembly governing complex physiological processes, and suggest new pathways for the development of biologically inspired photonic devices.