Phosphorylation of brain specific membrane proteins of developing chick embryo.
Phosphorylation of plasma membrane proteins in various tissues of chick embryos was investigated during the development. A polypeptide of Mr 22,000 was found to be the major phosphorylated plasma membrane protein in embryonic brain; this protein was absent in embryonic muscle, liver, and gizzard tissues. Extraction of plasma membranes with Triton X-100 (1%) or Nonidet p40 (1%) or sodium deoxycholate (1%) resulted in the solubilization of most membrane proteins including the 22 KDa phosphoprotein suggesting that the 22 KDa protein is a membrane-bound protein. Maximum phosphorylation of the 22 KDa protein by [gamma-32P]ATP was observed at 0.01 mM Ca2+. Higher concentrations of Ca2+ (2.5 mM) inhibited the phosphorylation of the 22 KDa protein whereas 3.5 mM Mg2+ stimulated the phosphorylation.
David
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E
School of Biological Sciences, Madurai Kamaraj University, India.
Shanmugam
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G
D000818:Animals; D001921:Brain / Q000196:embryology / Q000378:metabolism*; D002413:Cations, Divalent; D002642:Chick Embryo; D000242:Cyclic AMP / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism*; D008970:Molecular Weight; D010766:Phosphorylation; D011112:Polymyxin B / Q000494:pharmacology
D002413:Cations, Divalent; D008565:Membrane Proteins; D000242:Cyclic AMP; D011112:Polymyxin B