Flowering plants require three different nuclei in the pollen to travel and the sperm cell nuclei must travel through the pollen tube to reach the plant ovule.  Our collaboration with Yi Zhang’s group at Beijing Normal University is now available online with Nature Plants.  This work describes two kinesins that are involved in transporting the sperm nuclei in the pollen tube, providing insight into how plants ensure efficient fertilization without free-swimming sperm.

Yan, Y., Dai, L., Wang, B., Wang, T., Sun, Z., Wang, Y., Xing, C., Zhou, J., Luo, X., Zhu, Y., McFarlane, H.E., Gong, Y., Zhang, X., Xu, B., Hu, Y., Ren, H., and Zhang, Y. 2025. Kinesin proteins HUG1 and HUG2 are essential for the formation and transportation of male germ units in Arabidopsis pollen tubes. Nature Plants, 11: 1489-1499.

DOI: https://doi.org/10.1038/s41477-025-02064-z

Microscopy is an essential tool for plant biologists, but new users may face many challenges when working with plant samples. A panel of experts from the Plant Cell Atlas, led by Imaging Committee co-chairs Dr. Kirk Czymmek at the Donald Danforth Plant Science Centre and Prof. Heather E. McFarlane at the University of Toronto, have put together a manual for best practices in plant fluorescence imaging and reporting. This paper offers guidance to new and intermediate microscope users with the goal of making published microscopy data better aligned with FAIR (findability, accessibility, interoperability, and reusability) principles.

Czymmek, K.J.#, Benitez-Alfonso, Y., Burch-Smith, T., Di Costanzo, L.F., Drakakaki, G., Facette, M., Kierzkowski, D., Klebanovych, A., Radin, I., Roychoudhry, S. and McFarlane, H.E.#, 2025. Best practices in plant fluorescence imaging and reporting: A primer. The Plant Cell, 37: koaf143.

DOI: https://doi.org/10.1093/plcell/koaf143

Why does our lab study cell wall signaling? Plant cell walls are a critical source for raw materials. They provide dietary fibre in our food, and can be processed into natural, vegan textiles (like cotton, linen, and rayon), vegan gelling/thickening agents (such as pectins), green replacements to single use plastics (wood, paper, or compostable bioplastics), or renewable biofuels. Cell walls are therefore important targets for biotechnology, but attempts to modify plant cell walls have exposed a critical gap in the knowledge: plant cell wall modification can trigger cell wall signaling, which can limit plant growth. In our newest paper in the Canadian Journal of Plant Science, MSc student Gauen Shin reviews what is known about cell wall signaling and what knowledge gaps remain to be closed by ongoing research.

Shin, G. & McFarlane, H.E.# (2025) “Understanding cell wall signaling to open new opportunities for modifying plant cell walls.” Canadian Journal of Plant Sciences 105: 1-8.

DOI: https://dx.doi.org/10.1139/cjps-2024-0215

McFarLab PhD student Fabrizio Chow and MSc student Eskandar Mohammad have recently published our method for screening mutants for cell wall secretion defects. The protocol included detailed procedures, as well as troubleshooting steps, and example results for anyone who wants to apply this method to study their own mutants. Check out the paper in STAR Protocols for more details:

Chow, F., Mohammad, E., and McFarlane, H.E. “Protocol for detecting intracellular aggregations in Arabidopsis thaliana cell wall mutants using FM4-64 staining” Cell Press STAR Protocols 6: 103665.

DOI: https://doi.org/10.1016/j.xpro.2025.103665

Many components of the plant cell wall are made inside the cell at the Golgi apparatus and must be secreted before they can be integrated into the plant cell wall. Our new paper in Developmental Cell shows that the plant cell wall polysaccharide xyloglucan requires side chains for effective secretion following its biosynthesis in the Golgi apparatus. We showed that production of side-chain-deficient xyloglucan causes intracellular aggregations of proteins and polysaccharides. These results highlight the importance of polysaccharide structure for efficient secretion to the cell wall. This work was led by recent McFarLab PhD awardee Natalie Hoffmann and demonstrates that some cell wall modifications may need to occur after polysaccharide synthesis and secretion, suggesting that cell wall-localized, polysaccharide-modifying enzymes might make exciting targets for biotechnology.

Free access to the article is temporarily provided via this link.

DOI: https://doi.org/10.1016/j.devcel.2024.06.006

Our recent paper in PNAS on pectin synthesis has been highlighted by the prestigious journal Nature Plants.

Trösch, R. (2024) Elmo meets Quasimodo. Nature Plants 10, 693. https://doi.org/10.1038/s41477-024-01715-x

When plants encounter cell wall stress, they must presumably fortify the plant cell wall by synthesizing and secreting additional cell wall components. Our new paper in The Journal of Experimental Botany directly tests this hypothesis using live cell imaging and electron microscopy of plant samples across a range of cell wall stresses. We found that changes to cell wall integrity results in a rebalancing of the endomembrane system to promote secretion over endocytic trafficking. This work was led by recent McFarLab PhD awardee Natalie Hoffmann, with important contributions by MSc student Eskandar Mohammad, and is part of the JXB Special Issue on Exocytosis.

Free access is temporarily provided by the journal here.

https://doi.org/10.1093/jxb/erae195

Our collaborative work with Prof. Staffan Person at the University of Copenhagen to which Eduardo made important contributions is now available online at PNAS.

Cell walls are essential to cell morphogenesis, to protect plants against environmental stress, and for an array of products in our daily life. Pectins are essential components of plant cell walls that govern important agricultural characteristics, such as plant growth and development, fruit ripening, and seed pod shattering. In this study, we outline how a family of unknown proteins function as a scaffold for key synthesis components of pectin, a central cell wall polymer. Our results thus define a robust pectin synthesis protein complex that is essential for the structure and function of Golgi and for plant tissue integrity. These results add critical information regarding pectin synthesis and cell wall metabolons.

https://doi.org/10.1073/pnas.2321759121