The Inner Nuclear Membrane Is a Metabolically Active Territory that Generates Nuclear Lipid Droplets
| Autor: | Romanauska, Anete, Köhler, Alwin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Cell Nucleus
Lipin diacylglycerol Nuclear Envelope lipid sensors Membrane Proteins Phosphatidic Acids Lipid Droplets Saccharomyces cerevisiae Lipids Article inner nuclear membrane Diglycerides Membrane Lipids endoplasmic reticulum phosphatidic acid nuclear lipid droplets lipid metabolism lipids (amino acids peptides and proteins) Seipin transcription factor |
| Zdroj: | Cell |
| ISSN: | 1097-4172 0092-8674 |
| Popis: | Summary The inner nuclear membrane (INM) encases the genome and is fused with the outer nuclear membrane (ONM) to form the nuclear envelope. The ONM is contiguous with the endoplasmic reticulum (ER), the main site of phospholipid synthesis. In contrast to the ER and ONM, evidence for a metabolic activity of the INM has been lacking. Here, we show that the INM is an adaptable membrane territory capable of lipid metabolism. S. cerevisiae cells target enzymes to the INM that can promote lipid storage. Lipid storage involves the synthesis of nuclear lipid droplets from the INM and is characterized by lipid exchange through Seipin-dependent membrane bridges. We identify the genetic circuit for nuclear lipid droplet synthesis and a role of these organelles in regulating this circuit by sequestration of a transcription factor. Our findings suggest a link between INM metabolism and genome regulation and have potential relevance for human lipodystrophy. Graphical Abstract Highlights • INM is metabolically active and stores lipids via nuclear lipid droplets (nLDs) • Intranuclear lipid sensors detect DAG enrichment at INM and PA/DAG on nLDs • Nutrients and Opi1 transcriptional circuit regulate nLD synthesis • Lipodystrophy-related Seipin promotes formation of INM-nLD membrane bridges Active lipid metabolism and a distinct lipid composition of the inner nuclear membrane allow cells to produce nuclear lipid droplets. |
| Databáze: | OpenAIRE |
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