Lipid signalling

The oxysterol-binding protein-related protein 4 (ORP4L) is expressed in T-cell acute lymphoblastic leukemia and is required for leukemogenesis. Here the authors show that ORP4L orchestrates the transport of the phospholipid PI(4)P from Golgi to the plasma membrane, contributing to PI3K/AKT hyperactivation and T-cell leukemogenesis.

Dysregulation of plasmalogen metabolism in adipose tissue is associated with metabolic diseases. Here the authors characterize the role of adipocyte TMEM86A as a lysoplasmalogenase and show its deletion is protective against high fat diet induced metabolic disease, an effect that can be recapitulated by plasmenyl lysophosphatidylethanolamine 18:0 supplementation.

β-Adrenergic signaling is a core regulator of brown adipocyte function. Here, the authors provide unbiased insight into the transcriptional network controlled by lipolysis in brown adipocytes, showing that lipolysis is required for much of the thermogenic gene program activated by β-adrenergic signals.

Arya et al. identify a pathway for exosome generation in immune cells that originates at the nuclear envelope and is facilitated by nSMase1-mediated generation of ceramide.

The authors propose a new role for ADAR1, an RNA editing enzyme, in nonalcoholic fatty liver disease (NAFLD). Overexpression of ADAR1 ameliorates high-fat diet-induced liver injury and significantly abolishes NLRP3 inflammasome activation in THP-1 cells. Inhibition of ADAR1 expression causes a dramatic enhancement in NLRP3 inflammasome activation. Therefore, ADAR1 is a potential NAFLD suppressor through regulation of NLRP3 inflammasomes.

Phosphoinositides are signalling, membrane lipids derived from phosphatidylinositol, whose intracellular distribution and interconversion via phosphoinositide kinases and phosphatases is tightly coupled to membrane dynamics. Accordingly, phosphoinositides are now recognized as key regulators of endocytic and exocytic traffic, the autolysosomal system, and membrane contact site organization and function.