[en] RNA synthesis is activated in the cells of the plant embryo very soon after the start of seed imbibition. We previously reported that mainly heterogeneous nuclear RNA is synthesized in the radicle of Zea mays embryo during the first hours of germination. The present study was undertaken in order to detect the time of appearance of the newly synthesized messenger RNA in the polysomes of germinating maize axes.Free polysomes were prepared from embryonic axes rehydrated for 2 hours in the presence of radioactively labeled uridine. These polysomes were shown to be labeled and to contain labeled particles sedimenting, after dissociation with EDTA, in the 10S to 40S region of a sucrose gradient. The labeled polysomal RNA migrates heterogeneously in a gel with a mean size corresponding to about 16S, and 60% of these molecules are polyadenylated.The data indicate that the newly synthesized RNA associated with the polysomes after 2 h of germination consists of messenger RNA molecules. Analysis of the polysomes prepared 0.5 and 1 h after the start of imbibition suggests that translation of the newly synthesized messenger RNA probably occurs within the 1st hour of imbibition of the isolated axis, thus well before the completion of the initial water uptake.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Dommes, Jacques ; Université de Liège - ULiège > Département des sciences de la vie > Biologie moléculaire et biotechnologie végétales
Van de Walle, Claude ; Université de Liège - ULiège > Services généraux (Faculté des sciences) > Relations académiques et scientifiques (Sciences)
Language :
English
Title :
Newly Synthesized mRNA Is Translated During the Initial Imbibition Phase of Germinating Maize Embryo
Publication date :
October 1983
Journal title :
Plant Physiology
ISSN :
0032-0889
eISSN :
1532-2548
Publisher :
American Society of Plant Biologists, United States - Maryland