Functional organization of 3D plant thylakoid membranes as seen by high resolution microscopy.

Abstract

In the field of photosynthesis, only a limited number of approaches of super-resolution fluorescence microscopy can be used, as the functional architecture of the thylakoid membrane in chloroplasts is probed through the natural fluorescence of chlorophyll molecules. In this work, we have used a custom-built fluorescence microscopy method called Single Pixel Reconstruction Imaging (SPiRI) that yields a 1.4 gain in lateral and axial resolution relative to confocal fluorescence microscopy, to obtain 2D images and 3D-reconstucted volumes of isolated chloroplasts, obtained from pea (Pisum sativum), spinach (Spinacia oleracea) and Arabidopsis thaliana. In agreement with previous studies, SPiRI images exhibit larger thylakoid grana diameters when extracted from plants under low-light regimes. The three-dimensional thylakoid architecture, revealing the complete network of the thylakoid membrane in intact, non-chemically-fixed chloroplasts can be visualized from the volume reconstructions obtained at high resolution. From such reconstructions, the stromal connections between each granum can be determined and the fluorescence intensity in the stromal lamellae compared to those of neighboring grana.

Plant phenotyping relevance

植物葉緑体のチラコイド膜構造を高解像度・3D画像から抽出するカスタム蛍光顕微鏡法を開発・適用しており、植物形態・細胞内構造の表現型取得が中心である。

Code and data availability

The paper's phenotyping assets (SPiRI fluorescence microscopy images, 3D chloroplast volume reconstructions, grana diameter measurements, and custom R scripts for background removal) are not publicly deposited. The authors state data are available only on request; no public repository, code URL, or dataset identifier (

No evidence-backed public reproduction asset is currently recorded.