[Proline, a multifunctional amino-acid involved in plant adaptation to environmental constraints].

In addition to its role in primary metabolism as a component of proteins, proline is one of the most widely distributed compatible solutes that accumulates in plants during adverse environmental constraints and plays an important role in plant stress tolerance. Proline was proposed to act as stabilizer for proteins and macromolecular complexes, scavenger of free radicals and regulator of cellular redox potential. Intracellular proline concentration depends on a tight regulation between its biosynthesis and catabolism. However the exact role of proline and the signaling pathways involved in the regulation of its metabolism are not completely known yet. Investigation of proline metabolism in model plants would allow to acquire information about the diversity of the mechanisms developed by plants to overcome environmental constraints and to establish some reliable tools for the improvement of crop tolerance. © Société de Biologie, 2013.