Cell and tissue polarization is fundamental for plant growth and morphogenesis. The polar, cellular localization of Arabidopsis PIN‐FORMED (PIN) proteins is crucial for their function in directional auxin transport. The clustering of PIN polar cargoes within the plasma membrane has been proposed to be important for the maintenance of their polar distribution. However, the more detailed features of PIN clusters and the cellular requirements of cargo clustering remain unclear. Here, we characterized PIN clusters in detail by means of multiple advanced microscopy and quantification methods, such as 3D quantitative imaging or freeze‐fracture replica labeling. The size and aggregation types of PIN clusters were determined by electron microscopy at the nanometer level at different polar domains and at different developmental stages, revealing a strong preference for clustering at the polar domains. Pharmacological and genetic studies revealed that PIN clusters depend on phosphoinositol pathways, cytoskeletal structures and specific cell‐wall components as well as connections between the cell wall and the plasma membrane. This study identifies the role of different cellular processes and structures in polar cargo clustering and provides initial mechanistic insight into the maintenance of polarity in plants and other systems.
We thank Dr Ingo Heilmann (Martin‐Luther‐University Halle‐Wittenberg) for the XVE>>PIP5K1‐YFP line, Dr Brad Day (Michigan State University) for the ndr1‐1 mutant and the complementation lines, and Dr Patricia C. Zambryski (University of California, Berkeley) for the 35S::P30‐GFP line, the Bioimaging team (IST Austria) for assistance with imaging, group members for discussions, Martine De Cock for help in preparing the manuscript and Nataliia Gnyliukh for critical reading and revision of the manuscript. This project received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 742985) and Comisión Nacional de Investigación Científica y Tecnológica (Project CONICYT‐PAI 82130047). DvW received funding from the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme (FP7/2007‐2013) under REA grant agreement no. 291734.
Li H, von Wangenheim D, Zhang X, et al. Cellular requirements for PIN polar cargo clustering in Arabidopsis thaliana. New Phytologist. 2021;229(1):351-369. doi:10.1111/nph.16887
Li, H., von Wangenheim, D., Zhang, X., Tan, S., Darwish-Miranda, N., Naramoto, S., … Friml, J. (2021). Cellular requirements for PIN polar cargo clustering in Arabidopsis thaliana. New Phytologist. Wiley. https://doi.org/10.1111/nph.16887
Li, Hongjiang, Daniel von Wangenheim, Xixi Zhang, Shutang Tan, Nasser Darwish-Miranda, Satoshi Naramoto, Krzysztof T Wabnik, et al. “Cellular Requirements for PIN Polar Cargo Clustering in Arabidopsis Thaliana.” New Phytologist. Wiley, 2021. https://doi.org/10.1111/nph.16887.
H. Li et al., “Cellular requirements for PIN polar cargo clustering in Arabidopsis thaliana,” New Phytologist, vol. 229, no. 1. Wiley, pp. 351–369, 2021.
Li H, von Wangenheim D, Zhang X, Tan S, Darwish-Miranda N, Naramoto S, Wabnik KT, de Rycke R, Kaufmann W, Gütl DJ, Tejos R, Grones P, Ke M, Chen X, Dettmer J, Friml J. 2021. Cellular requirements for PIN polar cargo clustering in Arabidopsis thaliana. New Phytologist. 229(1), 351–369.
Li, Hongjiang, et al. “Cellular Requirements for PIN Polar Cargo Clustering in Arabidopsis Thaliana.” New Phytologist, vol. 229, no. 1, Wiley, 2021, pp. 351–69, doi:10.1111/nph.16887.
All files available under the following license(s):
Creative Commons Attribution 4.0 International Public License (CC-BY 4.0):
2021_NewPhytologist_Li.pdf 4.06 MB