Recent evidence corroborates the idea that the structure of the cycling nucleus is closely associated with ts ability to progress toward mitosis. The present project is firstly undertaken in order to explorate the nuclear chromatin structure and topological replicative pattern in the interphasic cells of onion root meristems. Chromatin changes are evaluated in terms of densiometric DNA measurements from the Feulgen-stained or PI-fluorescent nuclei and texture analysis from ultraestructural images. An intranuclear heterogenity of the replication site distribution could appear following the BrdUrd-labelling of replicated DNA. Measurements of BrdUrd incorporation patterns can be obtained from cytophotometry and image analysis after immunocytochemical reaction involving peroxidas-staining or FITC-fluorescence. Likewise, quantitative assessements of chromatin and replication patterns will be performed in the external granular layer of the rat cerebrall cortex. In order to relate nucleolar activity and interphase progress in meristematic cells, a morphometric analysis of subnucleolar localiztion of the B-36 protein will be done by inmunogold electron microscopy. We will also study the interphase timing of plant microtubule arrays by a double-immunofluorescence staining method for microtubules and intranuclear BrdUrd-pattern.
|Effective start/end date||21/12/97 → 21/12/00|