Membrane invaginations facilitate reversible water flux driving tunable iridescence in a dynamic biophotonic system

Daniel G. DeMartini, Daniel V. Krogstad, Daniel E. Morse

Research output: Contribution to journalArticle

Abstract

Squids have used their tunable iridescence for camouflage and communication for millions of years; materials scientists have more recently looked to them for inspiration to develop new "biologically inspired" adaptive optics. Iridocyte cells produce iridescence through constructive interference of light with intracellular Bragg reflectors. The cell's dynamic control over the apparent lattice constant and dielectric contrast of these multilayer stacks yields the corresponding optical control of brightness and color across the visible spectrum. Here, we resolve remaining uncertainties in iridocyte cell structure and determine how this unusual morphology enables the cell's tunable reflectance. We show that the plasma membrane periodically invaginates deep into the iridocyte to form a potential Bragg reflector consisting of an array of narrow, parallel channels that segregate the resulting high refractive index, cytoplasmic protein-containing lamellae from the low-index channels that are continuous with the extracellular space. In response to control by a neurotransmitter, the iridocytes reversibly imbibe or expel water commensurate with changes in reflection intensity and wavelength. These results allow us to propose a comprehensive mechanism of adaptive iridescence in these cells from stimulation to color production. Applications of these findings may contribute to the development of unique classes of tunable photonic materials.

Original languageEnglish (US)
Pages (from-to)2552-2556
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume110
Issue number7
DOIs
StatePublished - Feb 12 2013

Keywords

  • Doryteuthis opalescens
  • Iridophore
  • Structural color

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Membrane invaginations facilitate reversible water flux driving tunable iridescence in a dynamic biophotonic system'. Together they form a unique fingerprint.

  • Cite this