ESCRT-III-like proteins in bacteria: their role in membrane stress and repair
Membrane remodelling and repair in response to cellular stress is a fundamental requirement for all life. This process is mediated by protein families including Vipp1 (cyanobacteria), PspA (bacteria), and ESCRT-III (eukaryotes). In this talk, we will explore the structural and evolutionary evidence that shows these proteins to be homologous, suggesting a common origin predating the last universal common ancestor (LUCA). Cryo-EM and atomic force microscopy (AFM) are combined to reveal the remarkable capabilities of Vipp1 to build highly dynamic structures including, rings, sheets and spirals around membrane. Collectively, our data suggests a mechanism for Vipp1-mediated membrane stress response and repair in cyanobacteria and chloroplasts. It also has implication for how other homologues such as PspA, or the antibiotic induced LiaH, mitigate membrane stress across bacteria.