ZFIN ID: ZDB-PUB-060323-23
GLUT1 deficiency links nutrient availability and apoptosis during embryonic development
Jensen, P.J., Gitlin, J.D., and Carayannopoulos, M.O.
Date: 2006
Source: The Journal of biological chemistry   281(19): 13382-13387 (Journal)
Registered Authors: Gitlin, Jonathan D.
Keywords: none
MeSH Terms:
  • Animals
  • Apoptosis/physiology*
  • Cloning, Molecular
  • Deoxyglucose/metabolism
  • Embryo, Nonmammalian/metabolism*
  • Gene Deletion
  • Gene Expression Regulation, Developmental
  • Glucose/metabolism
  • Glucose Transporter Type 1/deficiency*
  • Glucose Transporter Type 1/metabolism
  • Phenotype
  • Zebrafish
  • Zebrafish Proteins/metabolism
  • bcl-Associated Death Protein/metabolism
PubMed: 16543226 Full text @ J. Biol. Chem.
GLUT1 is essential for human brain development and function as evidenced by the severe epileptic encephalopathy observed in children with GLUT1 deficiency syndrome resulting from inherited loss-of-function mutations in the gene encoding this facilitative glucose transporter. To further elucidate the pathophysiology of this disorder, the zebrafish orthologue of human GLUT1 was identified and expression of this gene abrogated during early embryonic development, resulting in a phenotype of aberrant brain organogenesis consistent with the observed expression of Glut1 in the embryonic tectum and specifically rescued by human GLUT1 mRNA. Affected embryos displayed impaired glucose uptake concomitant with increased neural cell apoptosis and subsequent ventricle enlargement, trigeminal ganglion cell loss and abnormal hindbrain architecture. Strikingly, inhibiting expression of the zebrafish orthologue of the proapoptotic protein Bad resulted in complete rescue of this phenotype and this occurred even in the absence of restoration of apparent glucose uptake. Taken together, these studies describe a tractable system for elucidating the cellular and molecular mechanisms of Glut1 deficiency and provide compelling in vivo genetic evidence directly linking nutrient availability and activation of mitochondrial-dependent apoptotic mechanisms during embryonic brain development.