Lipin proteins and glycerolipid metabolism: Roles at the ER membrane and beyond

摘要

Abstract The regulation of glycerolipid biosynthesis is critical for homeostasis of cellular lipid stores and membranes. Here we review the role of lipin phosphatidic acid phosphatase enzymes in glycerolipid synthesis. Lipin proteins are unique among glycerolipid biosynthetic enzymes in their ability to transit among cellular membranes, rather than remain membrane tethered. We focus on the mechanisms that underlie lipin protein interactions with membranes and the versatile roles of lipins in several organelles, including the endoplasmic reticulum, mitochondria, endolysosomes, lipid droplets, and nucleus. We also review the corresponding physiological roles of lipins, which have been uncovered by the study of genetic lipin deficiencies. We propose that the growing body of knowledge concerning the biochemical and cellular activities of lipin proteins will be valuable for understanding the physiological functions of lipin proteins in health and disease. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Highlights ? Lipin phosphatidate phosphatases are key enzymes in de novo glycerolipid biosynthesis. ? Lipins associate with phosphatidic acid in membranes in diverse cellular compartments. ? Lipin proteins act at the ER membrane, nucleus, mitochondria and autophagososme. ? Lipins are regulated via transcription, mRNA splicing, and protein modifications. ? Mendelian diseases are associated with mutations in LPIN1 and LPIN2 genes. ]]>