Signal-Mediated Cellular Retention and Subunit Assembly of Human Acetylcholinesterase

  • C. Kronman
  • Y. Flashner
  • A. Shafferman
  • B. Velan

Abstract

Kinetic analysis of human AChE T- subunit secretion by 293-HEK cells revealed preferential secretion of assembled dimers (Kerem et al., 1993). Secretion of ER resident enzymes is precluded through a signal mediated process involving a membrane-bound receptor (Munro and Pelham, 1987) which recognizes a specific signal at the COOH-termi-nus of the lumenal proteins (Pelham, 1990) of which the Acid-Leu terminus appears to be the most critical structural element in the interaction between the ER lumenal proteins and their cognate receptor (Pelham, 1990; Andres et al., 1991). The presence of a CSDL motif at the C-terminus of the AChE polypeptide could suggest the participation of a selective signal-mediated ER retrieval process in the preferential export of assembled AChE catalytic subunits. To examine this possibility, secreted and cell-associated enzymatic activities in transiently transfected cells expressing HuAChE carboxyl-terminus mutants were determined (See Table 1).

References

  1. Andres, D.A., Rhodes, J.D., Meisel, R.L., and Dixon, J.E. (1991). J. Biol. Chem. 266, 14277–14282.PubMedGoogle Scholar
  2. Kerem, A., Kronman, C., Bar-Nun, S., Shafferman, A. and Velan, B. (1993). J. Biol. Chem. 268, 180–184.PubMedGoogle Scholar
  3. Munro, S. and Pelham, H.R.B. (1987). Cell 48, 899–907.PubMedCrossRefGoogle Scholar
  4. Pelham, H.R.B. (1990). Trends Biochem. Sci. 15, 483–486.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • C. Kronman
    • 1
  • Y. Flashner
    • 1
  • A. Shafferman
    • 1
  • B. Velan
    • 1
  1. 1.Israel Institute Biological ResearchNess-ZionaIsrael

Personalised recommendations