Banfalvi Gaspar
Department of Microbial Biotechnology and Cell Biology, University of Debrecen, Debrecen, Hungary.
DNA Cell Biol. 2008 Feb;27(2):65-70. doi: 10.1089/dna.2007.0671.
Reversible permeable cells have been used to isolate chromatin structures during the process of chromosome condensation. Analysis of individual structures slipping out from nuclei after reversal of permeabilization revealed that chromosomes of Drosophila cells consist of small units called rodlets. The fluorescent images of chromatin fibers were subjected to computer analysis allowing the computer-aided visualization of chromatin fibers. The zig-zag array of fibers consisting of 12-15 nucleosomes with a length of 270-330 nm (average 300 nm) showed decondensed extended strings, condensed loops, and coiled condensed loops. Theoretical considerations leading to the plectonemic model of chromatin condensation are based on experimental data, and give an explanation how the 30 chromatin fibers are formed and further condensed to the 300 nm chromatin loops in Drosophila cells.
可逆渗透细胞已被用于在染色体浓缩过程中分离染色质结构。对透化作用逆转后从细胞核中滑出的单个结构进行分析发现，果蝇细胞的染色体由称为小杆的小单元组成。染色质纤维的荧光图像经过计算机分析，从而实现了染色质纤维的计算机辅助可视化。由12 - 15个核小体组成、长度为270 - 330纳米（平均300纳米）的纤维之字形阵列呈现出解聚的伸展链、浓缩环和卷曲浓缩环。导致染色质浓缩的超螺旋模型的理论考量基于实验数据，并解释了果蝇细胞中30纳米染色质纤维是如何形成并进一步浓缩为300纳米染色质环的。
