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Structure and function of lipid droplet assembly complexes.

ABSTRACT: Cells store lipids as a reservoir of metabolic energy and membrane component precursors in organelles called lipid droplets (LDs). LD formation occurs in the endoplasmic reticulum (ER) at LD assembly complexes (LDAC), consisting of an oligomeric core of seipin and accessory proteins. LDACs determine the sites of LD formation and are required for this process to occur normally. Seipin oligomers form a cage-like structure in the membrane that may serve to facilitate the phase transition of neutral lipids in the membrane to form an oil droplet within the LDAC. Modeling suggests that, as the LD grows, seipin anchors it to the ER bilayer and conformational shifts of seipin transmembrane segments open the LDAC dome toward the cytoplasm, enabling the emerging LD to egress from the ER.

SUBMITTER: Walther TC

PROVIDER: S-EPMC10853036 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Structure and function of lipid droplet assembly complexes.

Walther Tobias C TC Kim Siyoung S Arlt Henning H Voth Gregory A GA Farese Robert V RV

Current opinion in structural biology 20230505

Cells store lipids as a reservoir of metabolic energy and membrane component precursors in organelles called lipid droplets (LDs). LD formation occurs in the endoplasmic reticulum (ER) at LD assembly complexes (LDAC), consisting of an oligomeric core of seipin and accessory proteins. LDACs determine the sites of LD formation and are required for this process to occur normally. Seipin oligomers form a cage-like structure in the membrane that may serve to facilitate the phase transition of neutral ...[more]

PMID: 37150040

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