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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 in coloration and vision. However, little is known about how organisms regulate crystallization to produce optically useful morphologies which express highly reflective crystal faces. Guanine crystals form inside iridosome vesicles within chromatophore cells called iridophores. By following iridosome formation in developing scallop eyes, we show that pre-assembled, fibrillar sheets provide an interface for nucleation and direct the orientation of the guanine crystals. The macromolecular sheets cap the (100) faces of immature guanine crystals, inhibiting growth along the π-stacking growth direction. Crystal growth then occurs preferentially along the sheets to generate highly reflective plates. Despite their different physical properties, the morphogenesis of iridosomes bears a striking resemblance to melanosome morphogenesis in vertebrates, where amyloid sheets template melanin deposition. The common control mechanisms for melanin and guanine formation inspire new approaches for manipulating the morphologies and properties of molecular materials.

SUBMITTER: Wagner A

PROVIDER: S-EPMC9898273 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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

Wagner Avital A Upcher Alexander A Maria Raquel R Magnesen Thorolf T Zelinger Einat E Raposo Graça G Palmer Benjamin A BA

Nature communications 20230203 1

Animals precisely control the morphology and assembly of guanine crystals to produce diverse optical phenomena in coloration and vision. However, little is known about how organisms regulate crystallization to produce optically useful morphologies which express highly reflective crystal faces. Guanine crystals form inside iridosome vesicles within chromatophore cells called iridophores. By following iridosome formation in developing scallop eyes, we show that pre-assembled, fibrillar sheets prov ...[more]

PMID: 36737617

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Dataset Information

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

Publications

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

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