Updated project metadata. FAM134B is a reticulon-homology domain (RHD)-containing protein that participates in membrane-shaping of the endoplasmic reticulum (ER)8 13. It also functions as a mammalian ER-phagy receptor, mediating the fragmentation and selective degradation of ER sheets in multiple cell types8. However, little is known about the molecular and biophysical mechanisms that control and/or switch between these two FAM134B functions.