8EDV

Mitoguardin homolog (MIGA) delta TM residues 106-496 from Caenorhabditis elegans bound to modelled lipid phosphatidylethanolamine

Summary for 8EDV

• Entry DOI: 10.2210/pdb8edv/pdb
• Descriptor: MItoGuArdin homolog, DI-PALMITOYL-3-SN-PHOSPHATIDYLETHANOLAMINE (2 entities in total)
• Functional Keywords: lipid transport, mitochondria, lipid droplets
• Biological source: Caenorhabditis elegans
• Total number of polymer chains: 4
• Total formula weight: 183424.49

Authors

Hong, Z.,Adlakha, J.,Reinisch, K.M. (deposition date: 2022-09-06, release date: 2022-10-12, Last modification date: 2024-04-03)

Primary citation

Hong, Z.,Adlakha, J.,Wan, N.,Guinn, E.,Giska, F.,Gupta, K.,Melia, T.J.,Reinisch, K.M.
Mitoguardin-2-mediated lipid transfer preserves mitochondrial morphology and lipid droplet formation.
J.Cell Biol., 221:-, 2022

PubMed Abstract: Lipid transport proteins at membrane contacts, where organelles are closely apposed, are critical in redistributing lipids from the endoplasmic reticulum (ER), where they are made, to other cellular membranes. Such protein-mediated transfer is especially important for maintaining organelles disconnected from secretory pathways, like mitochondria. We identify mitoguardin-2, a mitochondrial protein at contacts with the ER and/or lipid droplets (LDs), as a lipid transporter. An x-ray structure shows that the C-terminal domain of mitoguardin-2 has a hydrophobic cavity that binds lipids. Mass spectrometry analysis reveals that both glycerophospholipids and free-fatty acids co-purify with mitoguardin-2 from cells, and that each mitoguardin-2 can accommodate up to two lipids. Mitoguardin-2 transfers glycerophospholipids between membranes in vitro, and this transport ability is required for roles both in mitochondrial and LD biology. While it is not established that protein-mediated transfer at contacts plays a role in LD metabolism, our findings raise the possibility that mitoguardin-2 functions in transporting fatty acids and glycerophospholipids at mitochondria-LD contacts.

PubMed: 36282247
DOI: 10.1083/jcb.202207022

Experimental method

X-RAY DIFFRACTION (3.3 Å)