Visualization of chromosome condensation in plants with large chromosomes

BMC Plant Biology

Research Article

Inna A. Chaban¹  Maria A. Kuznetsova²  Eugene V. Sheval³ 

[1] All-Russian Research Institute of Agricultural Biotechnology, Timiryazevskaja 42, 127550, Moscow, Russia;Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992, Moscow, Russia;Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992, Moscow, Russia;LIA 1066 LFR2O French-Russian Joint Cancer Research Laboratory, 94805, Villejuif, France;

关键词: Mitosis;    Chromosome;    Condensation;    Chromonema;    Plants;    Evolution;   

DOI  :  10.1186/s12870-017-1102-7

 received in 2017-06-23, accepted in 2017-09-07,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundMost data concerning chromosome organization have been acquired from studies of a small number of model organisms, the majority of which are mammals. In plants with large genomes, the chromosomes are significantly larger than the animal chromosomes that have been studied to date, and it is possible that chromosome condensation in such plants was modified during evolution. Here, we analyzed chromosome condensation and decondensation processes in order to find structural mechanisms that allowed for an increase in chromosome size.ResultsWe found that anaphase and telophase chromosomes of plants with large chromosomes (average 2C DNA content exceeded 0.8 pg per chromosome) contained chromatin-free cavities in their axial regions in contrast to well-characterized animal chromosomes, which have high chromatin density in the axial regions. Similar to animal chromosomes, two intermediates of chromatin folding were visible inside condensing (during prophase) and decondensing (during telophase) chromosomes of Nigella damascena: approximately 150 nm chromonemata and approximately 300 nm fibers. The spatial folding of the latter fibers occurs in a fundamentally different way than in animal chromosomes, which leads to the formation of chromosomes with axial chromatin-free cavities.ConclusionDifferent compaction topology, but not the number of compaction levels, allowed for the evolution of increased chromosome size in plants.

【 授权许可】

CC BY   
© The Author(s). 2017