Formation of xanthine and the use of purine metabolites as a nitrogen source in Arabidopsis plants

Abstract

In our recent paper in Plant J1, we described the remobilization of purine metabolites during natural and dark induced senescence in wild type and Atxdh1 mutant lines impaired in xanthine dehydrogenase (XDH), a pivotal enzyme in the purine catabolism pathway. In the light of these observations and additional evidence shown here, we discuss the probable pathways leading to xanthine synthesis in Arabidopsis plants during senescence and the role that purine metabolites play as an ongoing source of nitrogen in plant growth.Addendum to: Brychkova G, Alikulov Z, Fluhr R, Sagi M. A critical role for ureides in dark and senescence-induced purine remobilization is unmasked in the Atxdh1 Arabidopsis mutant. Plant J 2008; 54:496–509.