Abstract
Dissected Malpighian tubules from wild type and the eye color mutant white of Drosophila were compared with respect to their abilities to transport tryptophan and kynurenine into tubule cells. It was determined that mutation at white greatly impairs the ability of Malpighian tubule cells to take up tryptophan. Functional studies on the extracellular spaces and ultrastructural observations indicated no differences in these respects between wild type and white tubules. It is consistent with several observations that much of the tryptophan associated with white exists in the intercellular spaces. Furthermore, the uptake of tryptophan by the w + system of wild type tubules is inhibited by the analogue 5-methyl-tryptophan. However, the incorporation of radioactive tryptophan into protein in tubule cells from wild type and white occurs at the same rates and is not affected by 5-methyl-tryptophan. Therefore, it is apparent that Malpighian tubules have a transport system that enables entry of tryptophan into a cellular pool and that this cellular pool is initially independent of the tryptophan pool used for protein synthesis. The mutant white lacks this transport system. From these studies and others it appears that compartmentalization of cellular pools may be brought about via the utilization of specific membrane transport systems.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Biber, T. U. L., Cruz, L. J., and Curran, P. F. (1972). Sodium influx at the outer surface of frog skin. Evaluation of different extracellular markers. J. Membrane Biol. 7365–372.
Green, M. M. (1969). Controlling element mediated transpositions of the white gene in Drosophila melanogaster. Genetics 61429–441.
Howells, A. J., Summers, K. M. and Ryall, R. L. (1977). Developmental patterns of 3-hydroxykynurenine accumulation in white and various other eye color mutants of Drosophila melanogaster. Biochem. Genet. 151049–1059.
Johnson, T., and Riegel, J. A. (1977). Ultrastructural studies on the Malpighian tubule of the Pill millipede, Glomeris marginata (Vellers). Cell Tissue Res. 180357–366.
Khairallah, E. A., and Mortimore, G. E. (1976). Assessment of protein turnover in perfused rat liver. J. Biol. Chem. 2511375–1384.
Maddrell, S. H. P., and Gardiner, B. O. C. (1973). The passive permeability of insect Malpighian tubules to organic solutes. J. Exp. Biol. 60641–652.
Moore, P. A., Jayme, D. W., and Oxender, D. L. (1977). A role for aminoacyl-tRNA synthetases in the regulation of amino acid transport in mammalian cell lines. J. Biol. Chem. 2527427–7430.
Robb, J. A. (1969). Maintenance of imaginal discs of Drosophila melanogaster in chemically defined media. J. Cell Biol. 41876–885.
Shields, G., Dubendorfer, A., and Sang, J. (1975). Differentiation in vitro of larval cell types from early embryonic cells of Drosophila melanogaster. J. Embryol. Exp. Morph. 331959–1975.
Sullivan, D. T., and Sullivan, M. C. (1975). Transport defects as the physiological basis for eye color mutants in Drosophila melanogaster. Biochem. Genet. 13603–613.
Sullivan, D. T., Kitos, R. J., and Sullivan, M. C. (1973). Developmental and genetic studies on kynurenine hydroxylase from Drosophila melanogaster. Genetics 75651–661.
Sullivan, D. T., Bell, L. A., Paton, D. R., and Sullivan, M. C. (1979). Purine transport by Malpighian tubules of pteridine deficient eye color mutants of Drosophila melanogaster. Biochem. Genet. 17565–573.
Vidrich, A., Airhart, J., Bruno, M. K., and Khairallah, E. (1977). Compartmentation of free amino acids for protein biosynthesis. Biochem. J. (1977):257–266.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sullivan, D.T., Bell, L.A., Paton, D.R. et al. Genetic and functional analysis of tryptophan transport in Malpighian tubules of Drosophila . Biochem Genet 18, 1109–1130 (1980). https://doi.org/10.1007/BF00484342
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00484342