Premium
Image analysis of the chromatin organization in the nuclear domains of freeze fractured hepatocytes and lymphocytes
Author(s) -
Marinelli Fiorenzo,
Falcieri Elisabetta,
Squarzoni Stefano,
Coco Rosalba,
Zini Nicoletta,
Manzoli Lucia,
Maraldi Nadir Maris
Publication year - 1990
Publication title -
biology of the cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.543
H-Index - 85
eISSN - 1768-322X
pISSN - 0248-4900
DOI - 10.1016/0248-4900(90)90366-b
Subject(s) - nucleolus , heterochromatin , biology , chromatin , interphase , nucleus , cell nucleus , solenoid , nuclear pore , microbiology and biotechnology , biophysics , physics , biochemistry , dna , quantum mechanics
Summary— The complex organization of the interphase nucleus can be analyzed, by way of thin sectioning and also freeze‐fracture. This approach has previously been utilized in association with image analysis to quantitatively describe the organization of isolated rat liver nuclei and nuclear matrices. The main nuclear domains which, in section, present marked differences due to their electron‐density, can be identified in replicas with more complex procedures, based on the quantitative evaluation of the number of particles per unit area and mainly by using image analysis. A quantitative analysis of the nuclear substructures has been performed by way of image analysis on in situ nuclei of freeze‐fractured cells presenting marked differences in the heterochromatin quantity, such as hepatocytes and lymphocytes. The replicated nuclear particles have been classified according to their diameter and the obtained histograms have been quantitatively evaluated. The nuclear domains, heterochromatin, interchromatin, nucleolus, present characteristic ratios among the three main classes of particles; that is, ribonucleoproteins, solenoid filaments and solenoid fibre aggregates. The typical patterns of the nuclear domains can be further stressed by selecting a single class of particles and by examining its topographic localization. While interchromatin and nucleolar domains present a similar quantitative pattern in hepatocytes and lymphocytes, the heterochromatin of lymphocytes contains a significative higher percentage of solenoid aggregates than that of hepatocytes.