Ascorbate Peroxidase of Moss Dicranum scoparium: Gene Identification and Enzyme Activity.

In the present work, the APX gene encoding ascorbate peroxidase in the moss Dicranum scoparium was for the first time cloned and sequenced, and a high homology of APX with ascorbate peroxidase genes of the mosses Grimmia pilifera and Physcomitrella patens was shown. The structure of the protein was characterized using bioinfomatics approach, and the activity of the enzyme under abiotic stresses was studied. An increase in the activity of ascorbate peroxidase was detected during desiccation of D. scoparium shoots. When exposed to heat shock, a decrease in the activity of ascorbate peroxidase correlated with a decrease in the expression of APX. Conserved elements, which were found in the structure of ascorbate peroxidase gene and protein, indicate that these sequences are conserved in the plant genome during evolution, in support of the importance of this enzyme in maintaining cellular redox status.