Chloroplast nitrite uptake is enhanced in Arabidopsis PII mutants

FEBS Lett. 2008 Apr 2;582(7):1061-6. doi: 10.1016/j.febslet.2008.02.056. Epub 2008 Mar 4.


In higher plants, the PII protein is a nuclear-encoded plastid protein that regulates the activity of a key enzyme of arginine biosynthesis. We have previously observed that Arabidopsis PII mutants are more sensitive to nitrite toxicity. Using intact chloroplasts isolated from Arabidopsis leaves and (15)N-labelled nitrite we show that a light-dependent nitrite uptake into chloroplasts is increased in PII knock-out mutants when compared to the wild-type. This leads to a higher incorporation of (15)N into ammonium and amino acids in the mutant chloroplasts. However, the uptake differences do not depend on GS/GOGAT activities. Our observations suggest that PII is involved in the regulation of nitrite uptake into higher plant chloroplasts.

MeSH terms

  • Anion Transport Proteins / metabolism
  • Arabidopsis / drug effects
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / physiology*
  • Biological Transport
  • Chloroplasts / metabolism*
  • Diuron / pharmacology
  • Mutation
  • Nitrites / metabolism*
  • Nitrogen / metabolism
  • PII Nitrogen Regulatory Proteins / genetics
  • PII Nitrogen Regulatory Proteins / physiology*
  • Photosynthesis / drug effects


  • Anion Transport Proteins
  • Arabidopsis Proteins
  • Nitrites
  • PII Nitrogen Regulatory Proteins
  • PII protein, Arabidopsis
  • Diuron
  • Nitrogen