Abstract
An inherited amino acid transport deficiency results in low concentrations of glutathione (GSH) in the erythrocytes of certain sheep. Earlier studies based on phenotyping according to GSH concentrations indicated that the gene Tr H, which controls normal levels of GSH, behaves as if dominant or incompletely dominant to the allele Tr h, which controls the GSH deficiency. The present paper shows that when sheep are classified according to amino acid transport activity, the Tr H gene behaves as if codominant to Tr h. Erythrocytes from sheep homozygous for the Tr H gene exhibit rapid saturable l-alanine influx (apparent K m ,21.6mm; V max, 22.4 mmol/liter cells/hr). Cells from sheep homozygous for the Tr h gene exhibit slow nonsaturable l-alanine uptake (0.55 mmol/liter cells/hr at 50mm extracellular l-alanine). Cells from heterozygous sheep show saturable l-alanine uptake with a diminished V max (apparent K m, 19.1mm; V max, 12.7 mmol/liter cells/hr). These erythrocytes have a significantly lower GSH concentration than cells from Tr H, TrH sheep but similar intracellular levels of dibasic amino acids.
Similar content being viewed by others
References
Atrosi, F. (1979). Phenotypic and Genetic Association Between Production/Reproduction Traits and Blood Biochemical Polymorphic Characters in Finn Sheep Thesis, Faculty of Agriculture, University of Helsinki, Finland.
Beutler, E., Duron, O., and Kelly, B. M. (1963). Improved method for the determination of blood glutathione. J. Lab. Clin. Med. 61882.
Bliss, C. I., and James, A. T. (1966). Fitting the rectangular hyperbola. Biometrics 22573.
Ellory, J. C. (1977). The sodium pump in ruminant red cells. In Ellory, J. C., and Lew, V. L. (eds)., Transport in Red Cells Academic Press, London, p. 363.
Ellory, J. C., Tucker, E. M., and Deverson, E. V. (1972). The identification of ornithine and lysine at high concentrations in the red cells of sheep with an inherited deficiency of glutathione. Biochim. Biophys. Acta 279481.
Jarvis, S. M., and Young, J. D. (1978). Genetic control of nucleoside transport in sheep erythrocytes. Biochem. Genet. 161035.
Larsson, A. (1981). 5-Oxoprolinuria and other inborn errors related to the γ-glutamyl cycle. In Belton, N. R., and Toothill, C. (eds.), Transport in Inherited Disease MTP Press, Lancaster p. 277.
Smith, J. E., Lee, M. S., and Mia, A. S. (1974). Decreased γ-glutamylcysteine synthetase: The probable cause of glutathione deficiency in sheep erythrocytes. J. Lab. Clin. Med. 82713.
Tucker, E. M. (1975). The life span of glutathione-deficient red cells in Tasmanian Merino sheep. Res. Vet. Sci. 19343.
Tucker, E. M., and Kilgour, L. (1970). An inherited glutathione deficiency and a concomitant reduction in potassium concentration in sheep red cells. Experientia 26203.
Tucker, E. M., and Young, J. D. (1980). Biochemical changes during reticulocyte maturation in culture. A comparison of genetically different sheep erythrocytes. Biochem. J. 19233.
Tucker, E. M., Kilgour, L., and Young, J. D. (1976). The genetic control of red cell glutathione deficiencies in Finnish Landrace and Tasmanian Merino sheep and in crosses between these breeds. J. Agr. Sci. Cambr. 87315.
Tucker, E. M., Wright, P. C., and Young, J. D. (1977). Influence of arginase deficiency on amino acid concentrations in sheep erythrocytes with a normal and with a defective transport system for amino acids. J. Physiol. 271:47P.
Tucker, E. M., Young, J. D., and Crowley, C. (1981). Red cell glutathione deficiency. Clinical and biochemical investigations using sheep as an experimental model system. Br. J. Haematol. 48403.
Wright, P. C., Young, J. D., Mangan, J. L., and Tucker, E. M. (1977). An inherited arginase deficiency in sheep erythrocytes. J. Agr. Sci. Cambr. 88765.
Young, J. D., and Ellory, J. C. (1977). Substrate specificity of amino acid transport in sheep erythrocytes. Biochem. J. 16233.
Young, J. D. and Nimmo, I. A. (1975). GSH biosynthesis in glutathione-deficient erythrocytes from Finnish Landrace and Tasmanian Merino sheep. Biochim. Biophys. Acta 404132.
Young, J. D., and Wright, P. C. (1977). A simple spot-test for the detection of erythrocyte arginase deficiency. Clin Chim. Acta 79611.
Young, J. D., Nimmo, I. A., and Hall, J. G. (1975). The relationship between GSH, GSSG and non-GSH thiol in GSH-deficient erythrocytes from Finnish Landrace and Tasmanian Merino sheep. Biochim. Biophys. Acta 404124.
Young, J. D., Ellory, J. C., and Tucker, E. M. (1976). Amino acid transport in normal and glutathione-deficient sheep erythrocytes. Biochem. J. 15443.
Young, J. D., Jones, S. E. M., and Ellory, J. C. (1980). Amino acid transport in human and sheep erythrocytes. Proc. R. Soc. B. 209355.
Author information
Authors and Affiliations
Additional information
The authors are grateful to the M.R.C. for a Project Grant.
Rights and permissions
About this article
Cite this article
Young, J.D., Tucker, E.M. & Kilgour, L. Genetic control of amino acid transport in sheep erythrocytes. Biochem Genet 20, 723–731 (1982). https://doi.org/10.1007/BF00483969
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00483969