Coordination of triacylglycerol and cholesterol homeostasis by DHR96 and the Drosophila LipA homolog magro

Cell Metab. 2012 Jan 4;15(1):122-7. doi: 10.1016/j.cmet.2011.11.011. Epub 2011 Dec 22.

Abstract

Although transintestinal cholesterol efflux has been identified as an important means of clearing excess sterols, the mechanisms that underlie this process remain poorly understood. Here, we show that magro, a direct target of the Drosophila DHR96 nuclear receptor, is required in the intestine to maintain cholesterol homeostasis. magro encodes a LipA homolog that is secreted from the anterior gut into the intestinal lumen to digest dietary triacylglycerol. Expression of magro in intestinal cells is required to hydrolyze cholesterol esters and promote cholesterol clearance. Restoring magro expression in the intestine of DHR96 mutants rescues their defects in triacylglycerol and cholesterol metabolism. These studies show that the central role of the intestine in cholesterol efflux has been conserved through evolution, that the ancestral function of LipA is to coordinate triacylglycerol and cholesterol metabolism, and that the region-specific activities of magro correspond to the metabolic functions of its upstream regulator, DHR96.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cholesterol / metabolism*
  • Cholesterol Esters / metabolism
  • Drosophila / metabolism
  • Drosophila Proteins / antagonists & inhibitors
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Homeostasis / genetics
  • Mutation
  • Proventriculus / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Triglycerides / metabolism*

Substances

  • Cholesterol Esters
  • Drosophila Proteins
  • Hr96 protein, Drosophila
  • RNA, Small Interfering
  • Receptors, Cytoplasmic and Nuclear
  • Triglycerides
  • Cholesterol