UC Irvine

In nature, cephalopods’ astounding camouflage abilities are enabled by their sophisticated skin, that contains multiple types of cells acting as active optical elements, which can be actuated to enable the tunable optical properties of the skin, due to the presence of stimuli-responsive protein reflectin. First, we genetically engineer human cells to produce reflectin transiently and natively and extensively characterize those cells with three-dimensional holotomography, while demonstrating the potential of reflectin-based subcellular structures as high refractive index biomolecular reporters. Next, we establish chemical and electrical stimulation of our engineered human cells to alter the internal arrangements of reflectin-based structures and characterize such alterations with three-dimensional holotomography, while demonstrating the modeled optical properties of stimulated cells. Last, we extract single cells from squid skin tissue and characterize their subcellular structures with three-dimensional holotomography, while demonstrating the significance of subcellular morphological features for squid skin structural coloration. In summary, we enable a robust approach to systematically characterize engineered human single cells with three-dimensional holotomography, establish tunable optical properties of human cells and using three-dimensional data predict their optical properties, and determine the three-dimensional subcellular characteristics of squid skin cells that are responsible for their structural coloration.