Macromolecular sheets direct the morphology and orientation of plate-like biogenic guanine crystals

Abstract

Animals precisely control the morphology and assembly of guanine crystals to produce diverse optical phenomena but little is known about how organisms regulate crystallization to produce optically useful morphologies. Here, the authors demonstrate that pre-assembled, fibrillar sheets in developing scallop eyes template nucleation and direct the growth and orientation of plate-like guanine crystals showing a striking resemblance to melanosome morphogenesis.