Mechanism of branching morphogenesis inspired by diatom silica formation

Research output: Contribution to journalResearch articleContributedpeer-review

Abstract

The silica-based cell walls of diatoms are prime examples of genetically controlled, species-specific mineral architectures. The physical principles underlying morphogenesis of their hierarchically structured silica patterns are not understood, yet such insight could indicate novel routes toward synthesizing functional inorganic materials. Recent advances in imaging nascent diatom silica allow rationalizing possible mechanisms of their pattern formation. Here, we combine theory and experiments on the model diatom Thalassiosira pseudonana to put forward a minimal model of branched rib patterns-a fundamental feature of the silica cell wall. We quantitatively recapitulate the time course of rib pattern morphogenesis by accounting for silica biochemistry with autocatalytic formation of diffusible silica precursors followed by conversion into solid silica. We propose that silica deposition releases an inhibitor that slows down up-stream precursor conversion, thereby implementing a self-replicating reaction-diffusion system different from a classical Turing mechanism. The proposed mechanism highlights the role of geometrical cues for guided self-organization, rationalizing the instructive role for the single initial pattern seed known as the primary silicification site. The mechanism of branching morphogenesis that we characterize here is possibly generic and may apply also in other biological systems.

Details

Original languageEnglish
Article numbere2309518121
JournalProceedings of the National Academy of Sciences of the United States of America : PNAS
Volume121
Issue number10
Publication statusPublished - 5 Mar 2024
Peer-reviewedYes

External IDs

Scopus 85186278325
PubMed 38422023

Keywords

Keywords

  • Morphogenesis, Silicon Dioxide/chemistry, Diatoms/chemistry