Nutrients mobilized from leaves of Arabidopsis thaliana during leaf senescence

During leaf senescence nutrients are mobilized to seeds, storage organs or new vegetative growth. Here we determine the changes in the levels of vario us nutrients during leaf senescence in Arabidopsis thaliana. Levels of C, C r, Cu, Fe, K, Mo, N, P, S and Zn drop by greater than 40% during senescence indicating that these nutrients are mobilized from senescing leaves. Thus, for some elements, Arabidopsis is an effective model for the study of mobi lization during senescence. Mutations in two senescence-induced genes invol ved in copper transport, COPPER CHAPERONE and RESPONSIVE-TO-ANTAGONIST1 wer e identified. Nutrient mobilization is not affected in the cch-1 mutant ind icating that the CCH gene product does not play a role in this process or t hat a gene with redundant function exists. It was not possible to analyze n utrient mobilization in the ran 1-4 mutant due to the numerous pleiotropic effects of this mutation. Nevertheless, these experiments provide an approa ch for future studies of the molecular genetics of nutrient mobilization.