Figure 1.
Panel A: An illustration of the wild type ERMES complex. The complex includes Mmm1, Mdm12, Mdm34, and Mdm10, spanning the endoplasmic reticulum and outer mitochondrial membrane. Panel B: An illustration of Model 1, showing the lipid transporter Vps13 recruited to artificial ER-mitochondria contacts, with ChiMERA and Mcp1 present. Panel C: An illustration of Model 2, ChiMERA-integrated tethering requires Mdm12 and Mdm34 for structural stability, though their individual contributions to lipid flux remain redundant. Panel D: An illustration of Model 3, Mmm1 serves as the primary lipid transport protein, facilitated by external tethering. Mdm10 acts as the mitochondrial anchor for Mmm1, with ChiMERA integrated into the assembly to support overall stability.
Models for ChiMERA rescue of ERMES depletion. (A) Model of the heterotetrameric ERMES complex. (B) Model 1: The lipid transporter Vps13 is recruited to artificial ER–mitochondria contacts. (C) Model 2: Mdm12 and Mdm34 are essential for tethering but redundant with one another in lipid transport function. (D) Model 3: Mmm1 can function as the sole LTP if there is sufficient external tethering. Mdm10 supports lipid transfer by providing an anchoring point for Mmm1 to mitochondria.