Deciphering the role of the hendecad-repeat coiled-coil domain of TRIM72 in membrane curvature recognition

RING-type E3 ubiquitin ligases are functional multidomain proteins involved in diverse eukaryotic cellular processes. A major subfamily of RING-type ligases is the tripartite motif (TRIM)-containing protein family, whose members contain RING, B-box, coiled-coil, and variable C-terminal domains. Although the roles of individual TRIM domains are well understood, the function of the coiled-coil domain remains unclear owing to its structural complexity. In this study, we investigated the structural details of the coiled-coil domain of TRIM72 to elucidate its role in facilitating interactions with both concave and convex membranes. Cooperative interactions of the coiled-coil/coiled-coil and B-box/B-box domains were found to drive oligomerization, aiding in the recognition of phospholipid layers by the PRYSPRY domains. These insights provide a fundamental basis for understanding TRIM family E3 ligases and highlight their conserved molecular architecture and pattern recognition capabilities through higher-order assembly.