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Abstract Plasmodesmata (PD) are highly specialized, nanoscopic pores that traverse the cell wall to connect the cytoplasm of adjacent plant cells, enabling direct cell‐to‐cell communication. PD provides the continuity of three key cellular components: the plasma membrane, the endoplasmic reticulum (ER), and the cytosol. The compressed ER within PD is known as the desmotubule. PD mediates the intercellular trafficking of ions, metabolites, hormones, proteins, and RNA molecules between adjacent cells. Although several methods have been developed to quantify PD‐mediated molecular trafficking, it remains a technical challenge. Among these, PD‐mediated movement of fluorescent proteins is one of the most commonly used approaches. Here we present a microparticle bombardment method using a biolistic particle delivery system to investigate the PD‐mediated movement of fluorescent proteins. We equipped the delivery system with a flow guiding barrel to improve bombardment efficiency and consistency. We demonstrated the effects of gold particle aggregation and plant age on transformation efficiency and protein movement inArabidopsis. We also showed the feasibility of the method in determining PD‐mediated movement in tomato, pepper, and soybean. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Microparticle bombardment assay for measuring plasmodesmata‐mediated trafficking
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New insights into plasmodesmata: complex ‘protoplasmic connecting threads’
Abstract Intercellular communication in plants, as in other multicellular organisms, allows cells in tissues to coordinate their responses for development and in response to environmental stimuli. Much of this communication is facilitated by plasmodesmata (PD), consisting of membranes and cytoplasm, that connect adjacent cells to each other. PD have long been viewed as passive conduits for the movement of a variety of metabolites and molecular cargoes, but this perception has been changing over the last two decades or so. Research from the last few years has revealed the importance of PD as signaling hubs and as crucial players in hormone signaling. The adoption of advanced biochemical approaches, molecular tools, and high-resolution imaging modalities has led to several recent breakthroughs in our understanding of the roles of PD, revealing the structural and regulatory complexity of these ‘protoplasmic connecting threads’. We highlight several of these findings that we think well illustrate the current understanding of PD as functioning at the nexus of plant physiology, development, and acclimation to the environment.
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- Award ID(s):
- 2210127
- PAR ID:
- 10596579
- Editor(s):
- Lunn, John
- Publisher / Repository:
- Oxford University Press on behalf of the Society for Experimental Biology
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 75
- Issue:
- 18
- ISSN:
- 0022-0957
- Page Range / eLocation ID:
- 5557 to 5567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1093/jxb/erae307
