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691.
N M Maraldi F Marinelli R Ranaldi S Papa G M Mariuzzi F A Manzoli 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1986,8(4):343-348
Interphase rat liver nuclei were studied by freeze fracturing followed by electron microscopic observations. This method permits information on the native organization of the nuclear components in the hydrated state to be obtained. Morphometric analyses, performed with a Leitz Texture Analysis System, gave precise information on the different nuclear components, based on the histograms of their size distribution in heterochromatin, interchromatin and nucleolar areas. The textural characteristics were analyzed by computer to determine the topologic distribution of the solenoid chromatin fibers, the nucleosome filaments and the ribonucleoproteins in the different nuclear domains. 相似文献
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N M Maraldi F Marinelli S Papa A Galanzi F A Manzoli 《Basic and applied histochemistry》1987,31(3):421-428
Isolated nuclei represent a suitable model for studying the influence of exogenous phospholipids, normally found as minor chromatin components, on the nuclear structure, which, in turn, could be related to the observed modifications of DNA and RNA synthesis. The morphological modifications induced on chromatin RNP granules and nuclear matrix have been analyzed both with conventional thin sectioning and with an original method based on image analysis of freeze-fractured and replicated nuclear samples. The results obtained support the hypothesis that anionic phospholipids, by removing histone H1, induce a transition of the chromatin from solenoid to nucleosome conformation and favour the RNA polymerizing activity which results in an increased release of RNP particles, while neutral phospholipids, probably affecting the matrix structure, partly impare the RNP maturation and transport, with consequent increase of chromatin condensation. 相似文献
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Emidio Albertini Renzo Torricelli Elena Bitocchi Lorenzo Raggi Gianpiero Marconi Luciano Pollastri Gabriella Di Minco Alfredo Battistini Roberto Papa Fabio Veronesi 《Molecular breeding : new strategies in plant improvement》2011,27(4):533-547
The olive is considered one of the most important fruit crops of the Mediterranean basin where it shows a wide range of variability,
with about 2,000 cultivars. Italy, with about 500 cultivars, plays a fundamental role. The ability to discriminate olive cultivars
and estimate genetic variability are important factors in better management of genetic resources and in helping to understand
how genetic diversity is partitioned among cultivars. The two main objectives of the present investigation were to evaluate
the identity of cultivars grown in Abruzzo region, central Italy, and to study their genetic structure. We applied amplified
fragment length polymorphism (AFLP) methodology on 84 genotypes belonging to the most relevant and oldest varieties cultivated
in Abruzzo and on six unknown genotypes. The information content of data was evaluated using the Marker Ratio index and the
Polymorphic Index Content. Moreover, STRUCTURE software was used to investigate the genetic population structure. The analysis
enabled us to clearly distinguish eight cultivars within seven clusters. Additionally, one cluster was found to have various
minor cultivars and showed a relatively high level of diversity. The partitioning of genetic diversity showed that the largest
amount of molecular variance was within groups. Our data suggest that both sexual and clonal propagation have played an important
role in the evolution of olive cultivars. In our hypothesis, some ancestral population spread in central Italy with a relevant
role of seed propagation, followed by a selection of superior clones from which more traditional varieties originated. In
a few cases, hybridization should be taken into consideration to explain the diffusion of recently developed cultivars. 相似文献