Corpus ID: 9169003

Important role for phylogenetically invariant PP2Acalpha active site and C-terminal residues revealed by mutational analysis in Saccharomyces cerevisiae.

  title={Important role for phylogenetically invariant PP2Acalpha active site and C-terminal residues revealed by mutational analysis in Saccharomyces cerevisiae.},
  author={D. R. Evans and Brian A. Hemmings},
  volume={156 1},
PP2A is a central regulator of eukaryotic signal transduction. The human catalytic subunit PP2Acalpha functionally replaces the endogenous yeast enzyme, Pph22p, indicating a conservation of function in vivo. Therefore, yeast cells were employed to explore the role of invariant PP2Ac residues. The PP2Acalpha Y127N substitution abolished essential PP2Ac function in vivo and impaired catalysis severely in vitro, consistent with the prediction from structural studies that Tyr-127 mediates substrate… Expand
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