M. Mattana et al., EXPRESSION OF THE ENZYMES OF NITRATE REDUCTION DURING THE ANAEROBIC GERMINATION OF RICE, Plant physiology, 106(4), 1994, pp. 1605-1608
During the anaerobic germination of rice (Oryza sativa L.), nitrate is
translocated from the caryopsis and assimilated into the coleoptile (
R. Reggiani, M. Mattana, N. Aurisano, A. Bertani [1993] Plant Cell Phy
siol 34: 379-383). Using antibodies against nitrate and nitrite reduct
ases, proteins with the expected molecular mass were recognized by wes
tern blot analysis in extracts from 8-d-old rice coleoptiles. Both enz
ymes are de novo synthesized in 6- to 8-d-old seedlings, as shown by i
mmunoprecipitation of radiolabeled proteins from young plants grown in
the presence of [S-35]methionine. The anaerobic synthesis of both enz
ymes was enhanced by the addition of 5 mM KNO3. The effect of exogenou
s nitrate on the expression of the corresponding genes in anaerobic ri
ce coleoptiles was revealed by the analysis of their transcripts. The
importance of the expression of these enzymes during the anaerobic dev
elopment of rice seedlings is discussed.