Eukaryotic Transport Control: The Turnover Years
The years 1974 to 1979 marked a transition period for Herman Kalckar. While at the Massachusetts General Hospital, he moved out of the Biochemical Research Unit into the Huntington Laboratories and, subsequently, to the Chemistry Department at Boston University. It was during this five-year period of changes in personnel and sites of research activity, a turnover period, that the “Carrier Turnover Model” for the regulation of transport in animal cells was developed. The model was designed to explain how a balance between carrier synthesis, opposed by carrier degradation, is regulated by some, as yet unknown, process of oxidative glucose metabolism. Although the process is not linked to glycolysis, it is known to require an “energized state” of the cell. The energized state is, however, not dependent on the intracellular supply of ATP. Instead, the energized state appears to be crucial to the process of carrier degradation which apparently takes place through the action of lysosomal proteinases.
KeywordsBaby Hamster Kidney Chicken Embryo Fibroblast Hexose Transport Carrier Activity Amino Isobutyric Acid
Unable to display preview. Download preview PDF.
- Christopher, C.W., 1979, Proteolysis as a potential factor in hexose transport regulation in cultured animal cells, in: “Limited Proteolysis in Microorganisms,” G.N. Cohen and H. Holzer (eds.), D.H.E.W. Publication No. (NIH) 79–1591, U.S. Government Printing Office, Washington, D.C., p. 37.Google Scholar
- Franchi, A., Silvestre, P., and Pouyssegur, J., 1978, “Carrier activation” and glucose transport in Chinese hamster fibroblasts, Biochem. Biophys. Res. Commun., 85:1526.Google Scholar
- Nishino, H., Christopher, C.W., Schiller, R.M., Gammon, M.T., Ullrey, D., and Isselbacher, K.J., 1978, Sodium-dependent amino acid transport by cultured hamster cells: Membrane vesicles retain transport changes due to glucose starvation and cycloheximide, Proc. Natl. Acad. Sci. USA, 75: 5048.PubMedCrossRefGoogle Scholar