Site-specific regulatory interaction between spinach leaf sucrose-phosphate synthase and 14-3-3 proteins

FEBS Lett. 1998 Sep 11;435(1):110-4. doi: 10.1016/s0014-5793(98)01048-5.

Abstract

We report an Mg2+-dependent interaction between spinach leaf sucrose-phosphate synthase (SPS) and endogenous 14-3-3 proteins, as evidenced by co-elution during gel filtration and co-immunoprecipitation. The content of 14-3-3s associated with an SPS immunoprecipitate was inversely related to activity, and was specifically reduced when tissue was pretreated with 5-aminoimidazole-4-carboxamide riboside, suggesting metabolite control in vivo. A synthetic phosphopeptide based on Ser-229 was shown by surface plasmon resonance to bind a recombinant plant 14-3-3, and addition of the phosphorylated SPS-229 peptide was found to stimulate the SPS activity of an SPS:14-3-3 complex. Taken together, the results suggest a regulatory interaction of 14-3-3 proteins with Ser-229 of SPS.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • 14-3-3 Proteins
  • Amino Acid Sequence
  • Aminoimidazole Carboxamide / analogs & derivatives
  • Aminoimidazole Carboxamide / pharmacology
  • Binding Sites
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / metabolism
  • Enzyme Inhibitors / pharmacology
  • Glucosyltransferases / drug effects
  • Glucosyltransferases / metabolism*
  • Magnesium / metabolism
  • Molecular Sequence Data
  • Peptide Fragments / metabolism
  • Phosphorylation
  • Plant Leaves / drug effects
  • Plant Leaves / enzymology*
  • Proteins / metabolism*
  • Proteins / pharmacology
  • Ribonucleotides / pharmacology
  • Serine / metabolism
  • Spinacia oleracea / drug effects
  • Spinacia oleracea / enzymology*
  • Tyrosine 3-Monooxygenase*

Substances

  • 14-3-3 Proteins
  • Enzyme Inhibitors
  • Peptide Fragments
  • Proteins
  • Ribonucleotides
  • Aminoimidazole Carboxamide
  • Serine
  • Tyrosine 3-Monooxygenase
  • Glucosyltransferases
  • sucrose-phosphate synthase
  • AICA ribonucleotide
  • Magnesium