Evidence map›Paper›PMID 36251923›Full record

ArticleAdvanced science (Weinheim, Baden-Wurttemberg, Germany)2022

Gradients of Orientation, Composition, and Hydration of Proteins for Efficient Light Collection by the Cornea of the Horseshoe Crab.

Oliver Spaeker, Gavin J Taylor, Bodo D Wilts, Tomáš Slabý, Mohamed Ashraf Khalil Abdel-Rahman, Ernesto Scoppola, Clemens N Z Schmitt, Michael Sztucki, Jiliang Liu, Luca Bertinetti and 4 more

Open access · goldAbstract read
In one paragraph

Article in Advanced science (Weinheim, Baden-Wurttemberg, Germany), 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
1.3field-weighted citation impact, top 18% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 8 citations in OpenAlex.

  1. A Bio-Inspired Perspective on Materials Sustainability.Advanced materials (Deerfield Beach, Fla.) · 2025
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors at 6 institutions in 5 countries.

Oliver SpaekerDepartment of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Gavin J TaylorInstitute for Globally Distributed Open Research and Education (IGDORE), Ribeirão Preto, 14091-310, Brazil.
Bodo D WiltsChemistry and Physics of Materials, University of Salzburg, Jakob-Haringer-Str. 2a, Salzburg, 5020, Austria.
Tomáš SlabýTELIGHT, Libušina třída 21, Brno, 623 00, Czech Republic.
Mohamed Ashraf Khalil Abdel-RahmanTELIGHT, Libušina třída 21, Brno, 623 00, Czech Republic.
Ernesto ScoppolaDepartment of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Clemens N Z SchmittDepartment of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Michael SztuckiEuropean Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, CS 40220, Grenoble Cedex 9, 38043, France.
Jiliang LiuEuropean Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, CS 40220, Grenoble Cedex 9, 38043, France.
Luca BertinettiB CUBE - Center for Molecular Bioengineering, Technische Universität Dresden, 01307, Dresden, Germany.
Wolfgang WagermaierDepartment of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Gerhard ScholtzHumboldt-University Berlin, Institute of Biology, Philippstraße 13, 10115, Berlin, Germany.
Peter FratzlDepartment of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Yael PolitiB CUBE - Center for Molecular Bioengineering, Technische Universität Dresden, 01307, Dresden, Germany.ORCID 0000-0002-2872-8277
Max Planck Institute of Colloids and Interfaces · DEEuropean Synchrotron Radiation Facility · FRTechnische Universität Dresden · DEHumboldt-Universität zu Berlin · DEInstitute for Globally Distributed Open Research and Education · SEUniversity of Fribourg · CH

Funding

German Research Foundation 286895536
6 · The paper itself

Abstract

The lateral eyes of the horseshoe crab, Limulus polyphemus, are the largest compound eyes within recent Arthropoda. The cornea of these eyes contains hundreds of inward projecting elongated cuticular cones and concentrate light onto proximal photoreceptor cells. Although this visual system has been extensively studied before, the precise mechanism allowing vision has remained controversial. Correlating high-resolution quantitative refractive index (RI) mapping and structural analysis, it is demonstrated how gradients of RI in the cornea stem from structural and compositional gradients in the cornea. In particular, these RI variations result from the chitin-protein fibers architecture, heterogeneity in protein composition, and bromine doping, as well as spatial variation in water content resulting from matrix cross-linking on the one hand and cuticle porosity on the other hand. Combining the realistic cornea structure and measured RI gradients with full-wave optical modeling and ray tracing, it is revealed that the light collection mechanism switches from refraction-based graded index (GRIN) optics at normal light incidence to combined GRIN and total internal reflection mechanism at high incident angles. The optical properties of the cornea are governed by different mechanisms at different hierarchical levels, demonstrating the remarkable versatility of arthropod cuticle.

Indexed as

Horseshoe CrabsProteinsAnimalsCorneaPhotoreceptor CellsVision, OcularProteinsbiomaterialschitin-based materialsoptical materialsoptical modelingprotein compositionstructure-function relationshipsvision

Identifiers

PMID36251923
PMCPMC9685478
OpenAlexW4306646174

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.