Visual assessment of global chromatin intranuclear localization and its cellular diversification in mouse cells.

DNA is the core that controls the life activities of cells.In eukaryotic cells,DNA is dispersedly packaged into multiple strands of chromatin to regulate cellular life activities;however,the underlying logic and significance of this configuration remain unclear.In mouse cells,pericentromeric satellite DNA from multiple strands of chromatin can aggregate to form chromocenters[1,2].Based on microscopic imaging techniques and analysis,we further reveal that there is nonrandom recombination aggregation between chromatin in different mouse nuclei,leading to differentiation of nuclear structure and correlation with cell function.We speculate that the recombina-tion aggregation of chromatin nuclear localization can further enrich limited DNA genetic information,and its induced nuclear structural diversification is crucial for the formation of cellular diversification.The chromocenters of mouse cells are regions with abundant pericentromeric satellite DNA,which can be stained by DAPI to present a bright spot[3].Recent studies have revealed that the pericentromeric satellite DNA of mouse cells is involved in the intranuclear anchoring of chromatin[4],so the chromocenters can be used as the anchoring point of the chromatin,and then the chromatin of interphase cells can be observed.In this study,we found that the number of DAPI bright spots in the nucleus was not equal to the number of chromatin strips,and in many cases,it was much fewer than the number of chromatin strips[3,5](Figure 1A,B).In this regard,we speculate that the convergence of anchor points of different chromatin leads to a decrease in the number of observable chromocenters and part of the chromatin satellite DNA sequence is decompressed,so the highlighted spots cannot be displayed under the condition of DAPI labelling,causing a reduction in the observable chromocenter numbers.