A conserved dibasic site is essential for correct processing of the peptide hormone AtRALF1 in Arabidopsis thaliana

FEBS Lett. 2008 Oct 15;582(23-24):3343-7. doi: 10.1016/j.febslet.2008.08.025. Epub 2008 Sep 5.

Abstract

Prohormone proteins in animals and yeast are typically processed at dibasic sites by convertases. Propeptide hormones are also found in plants but little is known about processing. We show for the first time that a dibasic site upstream of a plant peptide hormone, AtRALF1, is essential for processing. Overexpression of preproAtRALF1 causes semi-dwarfism whereas overexpression of preproAtRALF1(R69A), the propeptide with a mutation in the dibasic site, shows a normal phenotype. RALF1(R69A) plants accumulate only the mutated proprotein and not the processed peptide. In vitro processing using microsomal fractions suggests that processing is carried out by a kexin-like convertase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence / genetics
  • Arabidopsis / anatomy & histology
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Arginine / genetics
  • Arginine / metabolism*
  • Cell Fractionation
  • Conserved Sequence / genetics
  • Microsomes / metabolism
  • Molecular Sequence Data
  • Mutation
  • Peptide Hormones / genetics
  • Peptide Hormones / metabolism*
  • Plant Leaves / anatomy & histology
  • Plant Leaves / genetics
  • Plant Leaves / metabolism
  • Plant Roots / anatomy & histology
  • Plant Roots / genetics
  • Plant Roots / metabolism
  • Plants, Genetically Modified / anatomy & histology
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism
  • Transformation, Genetic

Substances

  • Arabidopsis Proteins
  • Peptide Hormones
  • RALF1 protein, Arabidopsis
  • Arginine