Ribonucleases during ripening and after-ripening in Triticum durum embryos

Total and polyadenylated RNA content changes during ripening and after-ripening in embryos of Triticum durum cv. Cappelli. In this work, RNase activity was studied by means of enzymatic assays and activity staining SDS-PAGE in embryos at different stages of maturation and after-ripening. Qualitative and quantitative changes of RNases were found. Of particular interest was the continuous presence of acidic RNase in embryos, and the disappearance of neutral RNase activities during after ripening. Salt-inhibited RNases disappeared 42 days after anthesis, while salt-stimulated RNases with higher mobility disappeared in fully ripened embryos. Salt-stimulated RNases with lower mobility disappeared during after-ripening. The disappearance of neutral RNase activities during ripening may be related to the different physiological status induced by dehydration.