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bioRxiv · 10.1101/2021.01.04.425110

FAM134B-RHD Protein Clustering Drives Spontaneous Budding of Asymmetric Membranes

Siggel, M.·Bhaskara, R. M.·Moesser, M. K.·Dikic, I.·Hummer, G.
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Abstract

Living cells constantly remodel the shape of their lipid membranes. In the endo-plasmic reticulum (ER), the reticulon homology domain (RHD) of the reticulophagy regulator 1 (RETR1/FAM134B) forms dense autophagic puncta that are associated with membrane removal by ER-phagy. In molecular dynamics (MD) simulations, we find that FAM134B-RHD spontaneously forms clusters, driven in part by curvature-mediated attraction. At a critical size, the FAM134B-RHD clusters induce the formation of membrane buds. The kinetics of budding depends sensitively on protein concentration and bilayer asymmetry. Our MD simulations shed light on the role of FAM134B-RHD in ER-phagy and show that membrane asymmetry can be used to modulate the kinetics barrier for membrane remodeling. Graphical TOC Entry O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

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Siggel, M., Bhaskara, R. M., Moesser, M. K., Dikic, I., Hummer, G.. 2021-01-04. FAM134B-RHD Protein Clustering Drives Spontaneous Budding of Asymmetric Membranes. https://doi.org/10.1101/2021.01.04.425110

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