Biosynthesis of phosphatidylinositol-glycan (PI-G)-anchored membrane proteins in cell-free systems: cleavage of the nascent protein and addition of the PI-G moiety depend on the size of the COOH-terminal signal peptide.

@article{Kodukula1992BiosynthesisOP,
  title={Biosynthesis of phosphatidylinositol-glycan (PI-G)-anchored membrane proteins in cell-free systems: cleavage of the nascent protein and addition of the PI-G moiety depend on the size of the COOH-terminal signal peptide.},
  author={Krishna Kodukula and Douglas B. Cines and Rodolfo Amthauer and Louise Diekmann Gerber and Sidney Udenfriend},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  year={1992},
  volume={89 4},
  pages={
          1350-3
        }
}
Nascent translation products of PI-G-anchored membrane proteins contain both NH2- and COOH-terminal signal sequences of approximately 15-30 residues that are removed during processing. Removal of the latter occurs concomitant with the addition of the PI-G moiety to the newly formed COOH terminus. In human placental alkaline phosphatase (PLAP) the COOH-terminal signal peptide contains 29 residues. An engineered form of PLAP, miniPLAP 208, containing the same NH2- and COOH-terminal signal… 
Placental alkaline phosphatase: a model for studying COOH-terminal processing of phosphatidylinositol-glycan-anchored membrane proteins.
TLDR
Placental alkaline phosphatase has been used as a model for studying the biosynthesis of the phosphatidylinositol-glycan (PI-G)-protein linkage in intact cells and in cell-free systems but mutations adjacent and COOH-terminal to the omega site have revealed that the omega + 1 site is promiscuous in its requirements but that only glycine and alanine are effective at the omega - 2 site.
Comparative efficiencies of C‐terminal signals of native glycophosphatidylinositol (GPI)‐anchored proproteins in conferring GPI‐anchoring
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Recent developments in the molecular, biochemical and functional characterization of GPI8 and the GPI-anchoring mechanism [Review]
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The current aggregate of biochemical, gene-disruption and active site mutagenesis studies, which provide evidence that GPI8 is responsible for the protein-GPI anchoring reaction, are summarized.
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TLDR
Reconstitution of class K cells with hGPI8 abolishes their accumulation of G PI precursors and restores C-terminal processing of GPI-anchored proteins, and restores the ability of microsomes from the mutant cells to yield an active carbonyl in the presence of a proprotein, considered to be an intermediate in catalysis by a transamidase.
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TLDR
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The glycosylinositol phospholipid anchors of proteins such as Thy-1 of neurons and lymphocytes and the variant surface glycoprotein of African trypanosomes are posttranslationally linked to the C-terminus of the corresponding proteins, meaning that these proteins cannot be subject to many cytoplasmic events and impact on transmembrane proteins.
Glucose induces lipolytic cleavage of a glycolipidic plasma membrane anchor in yeast
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It is reported that transfer of yeast cells from lactate to glucose medium results in the conversion of the amphiphilic form of the cAMP receptor protein into a hydrophilic version accompanied by the rapid loss of fatty acids from the GPI anchor of the [14C]palmitic acid- labeled protein.
Proprotein interaction with the GPI transamidase
TLDR
The data indicate that recognition of the pro protein involves Gaa1p, that the interaction with the complex does not depend on a permissive ω site, and that Gpi8p forms a thioester intermediate with the proprotein.
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