Drosophila alpha-1,4-glycosyltransferase (alpha-4GT1) inhibits reaper-mediated apoptosis in the eye

Cell Tissue Res. 2009 Apr;336(1):149-58. doi: 10.1007/s00441-009-0758-1. Epub 2009 Feb 28.

Abstract

In a genetic screen, alpha-4GT1 has been identified as a potential enhancer of Hairless-mediated cell death in the eye of Drosophila. alpha-4GT1 encodes an alpha-1,4-glycosyltransferase, known to catalyze the fifth step in a series of ceramide glycosylation events. As reported for other enzymes involved in the glycosylation of ceramide, alpha-4GT1 is strongly expressed during oogenesis and is deposited maternally in the egg. Moreover, the protein is enriched at cell membranes. Unexpectedly, overexpression of alpha-4GT1 does not enhance Hairless-mediated cell death; instead, Hairless enhancement is caused by an allele of Scutoid present on the alpha-4GT1 chromosome. Interestingly, the downregulation of alpha-4GT1 during eye development amplifies cell death induction by the pro-apoptotic gene reaper. Accordingly, overexpression of alpha-4GT1 represses reaper-induced cell death. Thus, alpha-4GT1 appears to be an inhibitor of apoptosis, as has previously been observed for other ceramide glycosylating enzymes, suggesting that it likewise contributes to ceramide anchoring in the membrane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Apoptosis / drug effects
  • Apoptosis / genetics*
  • Crosses, Genetic
  • Down-Regulation / drug effects
  • Down-Regulation / genetics
  • Drosophila / embryology
  • Drosophila / enzymology*
  • Drosophila / genetics
  • Drosophila / metabolism
  • Drosophila Proteins / antagonists & inhibitors
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila Proteins / physiology*
  • Embryo, Nonmammalian
  • Epistasis, Genetic / physiology
  • Eye / drug effects
  • Eye / embryology*
  • Eye / metabolism
  • Gene Expression
  • Glycosyltransferases / genetics
  • Glycosyltransferases / metabolism
  • Glycosyltransferases / physiology*
  • Models, Biological
  • Ocular Physiological Phenomena / drug effects
  • Ocular Physiological Phenomena / genetics*
  • RNA, Small Interfering / pharmacology

Substances

  • Drosophila Proteins
  • RNA, Small Interfering
  • rpr protein, Drosophila
  • Glycosyltransferases
  • alpha4GT1 protein, Drosophila