These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Phosphopeptide mapping of Avena phytochrome phosphorylated by protein kinases in vitro.
    Author: McMichael RW, Lagarias JC.
    Journal: Biochemistry; 1990 Apr 24; 29(16):3872-8. PubMed ID: 2354157.
    Abstract:
    We previously demonstrated that protein kinases are useful probes of conformational changes that occur upon photoconversion of phytochrome [Wong, Y.-S., Cheng, H.-C., Walsh, D. A., & Lagarias, J. C. (1986) J. Biol. Chem. 261, 12089-12097]. Here we present phosphopeptide analyses of oat phytochrome phosphorylated by three mammalian protein kinases and by a polycation-stimulated, phytochrome-associated protein kinase. Phosphorylation of the Pr form by the cAMP-dependent protein kinase occurs predominantly on Ser17 while Ser598 is the preferred phosphorylation site on Pfr. The cGMP-dependent and Ca2(+)-activated, phospholipid-dependent protein kinases, which phosphorylate only the Pr form of phytochrome, recognize the same region on the phytochrome polypeptide as the cAMP-dependent protein kinase. Polycation-stimulated phytochrome phosphorylation reveals that, in contrast to the mammalian enzymes, the plant kinase recognizes the serine-rich, blocked N-terminus of phytochrome. The potential regulatory role of phytochrome phosphorylation, particularly in the structurally conserved serine/threonine-rich N-terminal region of the phytochrome polypeptide, is suggested by these results.
    [Abstract] [Full Text] [Related] [New Search]