The stability of maize nuclei to restriction enzyme digestion differs with transcriptional activity

The stability to restriction of nuclei obtained from plant cells of different transcriptional activity (dry embryo, root tip meristem and epicotyl protoplasts) has been studied. The morphological data obtained following fluorescent staining of nucleoid DNA with acridine orange indicate that the dry embryo structures are less stable than those actively involved in transcription, probably reflecting the lack of internal nuclear matrix structures in the dry embryo. The data support the suggestion for the key role these structures play in the functioning of the genome.