. Subtilisin-like serine proteases involved on N remobilization during grain filling in wheat

ROBERTS, I.N.; CAPUTO, CARLA; KADE M; CRIADO, M. VICTORIA; BARNEIX, ATILIO J

ACTA PHYSIOLOGIAE PLANTARUM

SPRINGER HEIDELBERG

Año: 2011 vol. 33 p. 1997 - 2001

0137-5881

The induction of two senescence-associated subtilisin-like proteases during the grain filling phase of wheat plants was evaluated by western blot. One of them, named P1 was detected very late in the life cycle of the plants (9 d post-anthesis) and seven days later reached a 2.5-fold increment respect to the initial value at flowering. The other one, named P2, was already detected previous to anthesis, and began to augment soon after flowering reaching a 4-fold increment by the end of the grain filling. These finding suggests the participation of both proteases in nitrogen remobilization from the flag leaf to the developing grains during natural senescence. Moreover, a differential role for each one of them is proposed. P2 is most likely directed to protein degradation for nitrogen reallocation, while P1 is synthesized late in senescence and presumably involved in the execution of cell death.