title: Comparative gene identification-58/α/β hydrolase domain 5: more than just an adipose triglyceride lipase activator?
abstract: OBJECTIVE
  Comparative gene identification-58 (CGI-58) is a lipid droplet-associated protein that controls intracellular triglyceride levels by its ability to activate adipose triglyceride lipase (ATGL). Additionally, CGI-58 was described to exhibit lysophosphatidic acid acyl transferase (LPAAT) activity. This review focuses on the significance of CGI-58 in energy metabolism in adipose and nonadipose tissue.
  
  
  RESULTS
  Recent studies with transgenic and CGI-58-deficient mouse strains underscored the importance of CGI-58 as a regulator of intracellular energy homeostasis by modulating ATGL-driven triglyceride hydrolysis. In accordance with this function, mice and humans that lack CGI-58 accumulate triglyceride in multiple tissues. Additionally, CGI-58-deficient mice develop an ATGL-independent severe skin barrier defect and die soon after birth. Although the premature death prevented a phenotypical characterization of adult global CGI-58 knockout mice, the characterization of mice with tissue-specific CGI-58 deficiency revealed new insights into its role in neutral lipid and energy metabolism. Concerning the ATGL-independent function of CGI-58, a recently identified LPAAT activity for CGI-58 was shown to be involved in the generation of signaling molecules regulating inflammatory processes and insulin action.
  
  
  CONCLUSIONS
  Although the function of CGI-58 in the catabolism of cellular triglyceride depots via ATGL is well established, further studies are required to consolidate the function of CGI-58 as LPAAT and to clarify the involvement of CGI-58 in the metabolism of skin lipids.
authors.affiliation: Institute of Molecular Biosciences, University of Graz, Graz, Austria.
authors.forename: Kathrin A
authors.initials: KA
authors.lastname: Zierler
authors.forename: Rudolf
authors.initials: R
authors.lastname: Zechner
authors.forename: Guenter
authors.initials: G
authors.lastname: Haemmerle
mesh_terms: D051103:1-Acylglycerol-3-Phosphate O-Acyltransferase / Q000737:chemistry* / Q000378:metabolism*; D000273:Adipose Tissue / Q000201:enzymology*; D000818:Animals; D004789:Enzyme Activation; D006801:Humans; D008049:Lipase / Q000378:metabolism*; D008066:Lipolysis; D017434:Protein Structure, Tertiary
chemical_list: D051103:1-Acylglycerol-3-Phosphate O-Acyltransferase; D008049:Lipase