The catalytic subunit of phosphatase 2A dephosphorylates phosphoopsin.

@article{Palczewski1989TheCS,
  title={The catalytic subunit of phosphatase 2A dephosphorylates phosphoopsin.},
  author={Krzysztof Palczewski and P. Hargrave and J. H. Mcdowell and Thomas S. Ingebritsen},
  journal={Biochemistry},
  year={1989},
  volume={28 2},
  pages={
          415-9
        }
}
Rod cell outer segments were found to contain a protein phosphatase activity toward phosphoopsin with properties very similar to those of protein phosphatase 1 or 2A. The opsin phosphatase activity was stable to ethanol precipitation, had a Mr of 35,000-38,000 as determined by gel filtration, and was not dependent on divalent cations for activity. The chromatographic properties on DEAE-cellulose of the rod outer segment protein phosphatase were also similar to those reported for protein… Expand
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Study of the ability of four highly purified well characterized protein phosphatases to dephosphorylate preparations of rhodopsin or beta 2-adrenergic receptor which had been highly phosphorylated by beta-adenergic receptor kinase suggests a potential role for the latent phosphatase 2 as a specific receptor phosphat enzyme. Expand
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The use of uncharacterized phosphoprotein substrates for the isolation of protein phosphatases necessitates the identification of the 32P-labeled phosphoamino acids present in the substrates and the analysis of their specific dephosphorylation. Expand
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TLDR
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TLDR
Kinetic analysis indicated that both LP-1 and LP-2 enzymes dephosphorylate histone 2A, myelin basic protein, and phosphorylase a at a rather comparable rate, but the deph phosphorylation of hist one 2A and myelinbasic protein seems to be spontaneously active, supporting the notion that a two-site mechanism may possibly be involved in the regulation of substrate specificity of LP- 1 and LP -2 enzymes in the central nervous system. Expand
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TLDR
The remarkable similarities between starfish oocyte protein phosphatases and their mammalian counterparts are indicative of strict phylogenetic conservation of these enzymes. Expand
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