NUCLEAR SIZE, DNA CONTENT, AND CHROMATIN CONDENSATION ARE DIFFERENT IN INDIVIDUAL TISSUES OF THE MAIZE ROOT APEX

Nuclei of various tissues exhibit different structure in the maize root apex. Moreover, the nuclear structure is in close correlation with the DNA and RNA synthesis. These observations are in contradiction with the hypothesis according to which the chromatin organization in plant nuclei is species-specific and does not correspond to the metabolic activity of nuclei. The possible reasons for this disagreement are discussed. The extended state of chromatin is not the passive result of synthetic processes in the nucleus, but, on the contrary, it is one of the primary factors which are indispensable for the DNA transcription. Results presented here together with data from literature suggest that the organization of chromatin complex appears as a general control mechanism which determines the efficiency of other more specific mechanisms. © 1990 Springer-Verlag.