Mutations in a Sar1 GTPase of COPII vesicles are associated with lipid absorption disorders

@article{Jones2003MutationsIA,
  title={Mutations in a Sar1 GTPase of COPII vesicles are associated with lipid absorption disorders},
  author={Bethan S. Jones and Emma Jones and Stephanie A. Bonney and Hetal N. Patel and Arjen R Mensenkamp and Sophie Eichenbaum-Voline and Mats Rudling and Urban Myrdal and Grazia Annesi and Sandhia Naik and N J Meadows and Aldo Quattrone and Suhail A. Islam and Rossitza P. Naoumova and Bo Angelin and Recaredo Infante and Emile Levy and Claude C. Roy and Paul S. Freemont and James Scott and Carol C. Shoulders},
  journal={Nature Genetics},
  year={2003},
  volume={34},
  pages={29-31}
}
Dietary fat is an important source of nutrition. Here we identify eight mutations in SARA2 that are associated with three severe disorders of fat malabsorption. The Sar1 family of proteins initiates the intracellular transport of proteins in COPII (coat protein)-coated vesicles. Our data suggest that chylomicrons, which vastly exceed the size of typical COPII vesicles, are selectively recruited by the COPII machinery for transport through the secretory pathways of the cell. 
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This study highlights the importance of fatty acid targeting in regulating chylomicron production by finding that knockdown of CD36 or FABP1 using short-hairpin RNA interference techniques would impair triacylglycerol (TG) and apolipoprotein B (apoB) secretion.
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