Bacterial Vipp1 and PspA are members of the ancient ESCRT-III membrane-remodelling superfamily

Published: Aug. 14, 2020, 10:02 a.m.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.13.249979v1?rss=1 Authors: Liu, J., Tassinari, M., Souza, D. P., Naskar, S., Noel, J. K., Bohuszewicz, O., Buck, M., Williams, T. A., Baum, B., Low, H. H. Abstract: Membrane remodelling and repair are essential for all cells. Proteins that perform these functions include Vipp1/IM30 in photosynthetic plastids, PspA in bacteria, CdvB in TACK archaea and ESCRT-III in eukaryotes. Here, we show that these protein families are homologous and share a common evolutionary origin. Using cryo-electron microscopy we present structures for Vipp1 rings over a range of symmetries. Each ring is built from rungs that stack and spontaneously self-organise to form domes. Rungs are assembled from a polymer that is strikingly similar in structure to ESCRT-III. A tilt between rungs generates the dome-shaped curvature with constricted open ends and an inner membrane-binding lumen. Overall, our results reveal conserved mechanistic principles that underlie Vipp1, PspA and ESCRT-III dependent membrane remodelling across all domains of life. Copy rights belong to original authors. Visit the link for more info