The ER-PM interaction is essential for cytokinesis and recruits the actin cytoskeleton through the SCAR/WAVE complex

Xu, Zhijing; Zang, Jingze; Zhang, Xintong; Zheng, Qiwei; Li, Yifan; Field, Nadine; Fiserova, Jindriska; Hua, Bing; Qu, Xiaolu; Kriechbaumer, Verena; Deeks, Michael J.; Hussey, Patrick J.; Wang, Pengwei

Abstract

Plant cytokinesis requires coordination between the actin cytoskeleton, microtubules 32 and membranes to guide division plane formation and cell plate expansion; how these 33 regulatory factors are coordinated remains unknown. The actin cytoskeleton assembly 34 is controlled by several actin nucleation factors, such as the SCAR/WAVE complex, 35 which regulates actin nucleation and branching through the activation of the ARP2/3 36 complex. The activity of these actin regulatory proteins is likely influenced by 37 interactions with specific membranes; however, the molecular basis and the biological 38 relevance of SCAR-membrane interactions are also unclear. In this study, we 39 demonstrate that the ER-PM tethering protein VAP27-1 directly interacts with 40 SCAR2 at the ER membrane, and that they co-localise to guide cell plate orientation 41 during cell division. In the root meristem, both VAP27-1 and SCAR2 exhibit 42 polarised localisation at the cell plates, where the interaction between ER and PM is 43 abundant. VAP27-1 recruits SCAR2 to the cell division plane, where there is a high 44 concentration of actin filaments. In the vap27-1346 mutant, the densities of cortical 45 ER, SCAR2 and consequently actin filaments are significantly reduced at the cell 46 division plane, affecting cell plate orientation, cell division and root development. A 47 similar phenomenon is also observed in the scar1234 mutant, suggesting that VAP27 48 and SCAR proteins regulate cell division through a similar pathway. In conclusion, 49 our data reveal a plant-specific function of VAP27-regulated ER-PM interaction and 50 advance our understanding of plant ER-PM contact site and its role in cell division.

Citation

Xu, Z., Zang, J., Zhang, X., Zheng, Q., Li, Y., Field, N., Fiserova, J., Hua, B., Qu, X., Kriechbaumer, V., Deeks, M. J., Hussey, P. J., & Wang, P. (2025). The ER-PM interaction is essential for cytokinesis and recruits the actin cytoskeleton through the SCAR/WAVE complex. Proceedings of the National Academy of Sciences, 122(6), Article e2416927122. https://doi.org/10.1073/pnas.2416927122

• Journal Article Type: Article
• Acceptance Date: Dec 27, 2024
• Online Publication Date: Feb 6, 2025
• Publication Date: Feb 6, 2025
• Deposit Date: Jan 14, 2025
• Publicly Available Date: Feb 6, 2025
• Journal: Proceedings of the National Academy of Sciences
• Print ISSN: 0027-8424
• Electronic ISSN: 1091-6490
• Publisher: National Academy of Sciences
• Peer Reviewed: Peer Reviewed
• Volume: 122
• Issue: 6
• Article Number: e2416927122
• DOI: https://doi.org/10.1073/pnas.2416927122
• Public URL: https://durham-repository.worktribe.com/output/3333722