Anti-C19ORF80 polyclonal antibody

The thyroid hormone, T-3, regulates cell growth, differentiation and development through binding to the nuclear thyroid hormone receptor (THR), a member of the steroid/TR superfamily of ligand-dependent transcriptional factors. T-3 modulates lipid metabolism in liver, although the detailed molecular mechanisms are unclear at present. Here, by a microarray analysis, we identified a novel chromosome 19 open reading frame 80 (C19orf80) which was activated by T-3. T-3 stimulation led to upregulation of both mRNA and protein levels of C19orf80. Immunofluorescence analysis revealed a vesicle-like pattern of C19orf80 around lipid droplets or within the lysosome-associated compartment in cells. Furthermore, T-3 treatment as well as C19orf80 overexpression specifically activated the autophagic response and lipid metabolism, as observed from lipidated LC3 (LC3-II) and levels of oxygen consumption rate, respectively. Reciprocally, knockdown of C19orf80 obstructed T-3-activated autophagy and lipolysis. Moreover, treatment with autolysosome maturation inhibitors, ammonium chloride and chloroquine, not only suppressed the T-3-activated autophagic process but also lipid metabolism. Our results collectively suggested that T-3 regulates lipid metabolism through a C19orf80-activated autophagic process.

The metabolic syndrome, a common disorder including glucose intolerance and dyslipidemia, poses a major public health issue. Patients with high blood lipids, such as triglycerides, are at high risk in developing atherosclerotic cardiovascular diseases. To identify genes involved in metabolism, we performed RNA-seq experiments on the liver and fat in mice treated with a high-fat diet or fasting, and identified Gm6484 (named Lipasin) as a novel nutritionally regulated gene. Human LIPASIN is liver specific, while the mouse one is enriched in the liver and fat, including both brown and white adipose tissues. Obesity increases liver Lipasin, whereas fasting reduces its expression in fat. ANGPTL3 (Angiopoietin-like 3) and ANGPTL4 are critical regulators of blood lipids. LIPASIN shares homology with ANGPTL3's N-terminal domain that is needed for lipid regulation, and with ANGPTL4's N-terminal segment that mediates lipoprotein lipase (LPL) binding. Lipasin overexpression by adenoviruses in mice increases serum triglyceride levels, and a recombinant Lipasin inhibits LPL activity. Therefore, a potential mechanism for Lipasin-mediated triglyceride elevation is through reduced triglyceride clearance by LPL inhibition. Lipasin is thus a novel nutritionally-regulated liver-enriched factor that plays a role in lipid metabolism. (c) 2012 Elsevier Inc. All rights reserved.