Lipid droplets degradation mechanisms from microalgae to mammals, a comparative overview
Résumé
Lipid droplets (LDs) are organelles composed of a hydrophobic core (mostly triacylglycerols and steryl esters) delineated by a lipid monolayer and found throughout the tree of life. LDs were seen for a long time as simple energy storage organelles but recent works highlighted their versatile roles in several fundamental cellular processes, particularly during stress response. LDs biogenesis occurs in the ER and their number and size can be dynamically regulated depending on their function, e.g. during development or stress. Understanding their biogenesis and degradation mechanisms is thus essential to better apprehend their roles. LDs degradation can occur in the cytosol by lipolysis or after their internalization into lytic compartments (e.g. vacuoles or lysosomes) using diverse mechanisms that depend on the considered organism, tissue, developmental stage or environmental condition. In this review, we summarize our current knowledge on the different LDs degradation pathways in several main phyla of model organisms, unicellular or pluricellular, photosynthetic or not (budding yeast, mammals, land plants and microalgae). We highlight the conservation of the main degradation pathways throughout evolution, but also the differences between organisms, or inside an organism between different organs. Finally, we discuss how this comparison can help to shed light on relationships between LDs degradation pathways and LDs functions.
Mots clés
fatty acid
LD
Lipid droplet
MAG
monoacylglycerol
mTOR
mechanistic target of rapamycin
PtdIns
Lipid droplets Lipolysis Lipophagy AMPK
Adenosine monophosphate-activated protein kinase (AMPK) CE
cholesteryl ester CMA
chaperone-mediated autophagy DAG
diacylglycerol ER
endoplasmic reticulum ESCRT
endosomal sorting complex required for transport FA
fatty acid LD
Lipid droplet MAG
monoacylglycerol mTOR
mechanistic target of rapamycin PtdIns
Adenosine monophosphate-activated protein kinase (AMPK)
CE
cholesteryl ester
CMA
chaperone-mediated autophagy
DAG
diacylglycerol
ER
endoplasmic reticulum
ESCRT
endosomal sorting complex required for transport
FA
Domaines
Biologie cellulaireOrigine | Publication financée par une institution |
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licence |