Subcellular compartmentation of proline in the leaves of the subantarctic Kerguelen cabbage Pringlea antiscorbutica R-Br. in vivo 13C-NMR study

Proline is one of the major solutes accumulated upon salt stress in leaves, stem and roots of the subantarctic Brassicaceae Pringlea antiscorbutica R, Br. (Kerguelen cabbage). Using in vivo (13)C-NMR techniques, it was possible for the first time to visualize the subcellular compartmentation of proline between cytoplasmic and vacuolar compartments in Pringlea leaves. We observed that this osmolyte accumulated at a 2-3 times higher concentration in the cytoplasm than in the vacuole.