Plants in the expansion era: recent advances in expansion microscopy in plant systems

Expansion microscopy is an imaging method that overcomes the resolution barriers of traditional diffraction-limited light microscopes via isotropic physical expansion of biological cells, tissues, and organisms. This technique enhances the ability to visualize proteins, nucleic acids, and other biomolecules at nanoscale resolutions. While this approach has predominantly been applied to biomedical applications, workflows for plant systems have emerged. Here we review the development of expansion microscopy methods for the plant kingdom. These advances range from isolated organelles, single cells, and unicellular organisms to whole organs, embryos, and reproductive tissues. We highlight the unique advantages and findings from individual techniques and provide a perspective of potential directions that expansion microscopy can be applied to answer important plant research questions.