Cell
Volume 52, Issue 6, 25 March 1988, Pages 915-924
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The yeast GTP-binding YPT1 protein and a mammalian counterpart are associated with the secretion machinery

https://doi.org/10.1016/0092-8674(88)90433-3Get rights and content

Abstract

A yeast GTP-binding protein, the YPT1 gene product, has been found to function early in the secretion pathway. The ypt1-1mutation causes a phenotype reminiscent of early secretion-defective mutants, including accumulation of membranes and vesicles as well as a partial defect in secretion and incomplete glycosylation of invertase. Immunofluorescence localization studies using affinity-purified antibody directed against the YPT1 protein showed punctate staining of the cytoplasm of growing yeast cells and very intense staining of small buds, where membrane growth and secretion are most active. The punctate cytoplasmic staining is changed in a mutant (sec7) under conditions that cause aberrant Golgi structures to accumulate. The pattern of immunofluorescence obtained when mouse cells were stained with the antibody coincided closely with the pattern observed with wheat germ agglutinin, suggesting that a mammalian counterpart of the yeast YPT1 protein is located in the Golgi apparatus. These results are interpreted as suggesting that GTP-binding proteins may act to direct intracellular vesicle traffic.

References (36)

  • A.E.M. Adams et al.

    Relationship of actin and tubulin distribution to bud growth in wild-type and morphogeneticmutant Saccharomyces cerevisiae

    J. Cell Biol.

    (1984)
  • M. Barbacid

    ras genes

    Annu. Rev. Biochem.

    (1987)
  • D. Bar-Sagi et al.

    Induction of membrane ruffling and fluid-phase pinocytosis in quiescent fibroblasts by ras proteins

    Science

    (1986)
  • R.D. Burgoyne

    Control of exocytosis

    Nature

    (1987)
  • M. Carlson et al.

    The secreted form of invertase in Saccharomyces cerevisiae is synthesized from n-RNA encoding a signal sequence

    Mol. Cell Biol.

    (1983)
  • T. Connolly et al.

    Formation of a functional ribosome-membrane junction during translocation requires the participation of a GTP-binding protein

    J. Cell Biol.

    (1986)
  • D. Gallwitz et al.

    A yeast gene encoding a protein homologous to the human C-has1bas proto-oncogene product

    Nature

    (1983)
  • A.G. Gilman

    G proteins transducers of receptor-generated signals

    Annu. Rev. Biochem.

    (1987)
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