Chromosome separation and segregation in dinoflagellates and bacteria may depend on liquid crystalline states
Chromosome separation and segregation in dinoflagellates and bacteria may depend on liquid crystalline states
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DOI：
10.1016/s0300-9084(00)01211-6
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发表时间：
2001-02-01
期刊：
影响因子：
3.9
通讯作者：
Norris, V
中科院分区：
文献类型：
--
作者：
Bouligand, Y;Norris, V
在鞭毛藻和细菌染色体的薄片中观察到某些液晶的特征模式，称为“扭曲向列线”或“胆固醇”。这些液晶也在体外浓缩的DNA溶液中得到。原核生物染色体中的大部分DNA形成这样一个扭曲的液晶，而其余的则由横向环组成，并且不太集中。这些半有序的阶段可以帮助染色体分离发生在DNA复制期间和之后。我们认为，由于化学差异，两条复制的细丝中的一条与该染色体中其余的DNA不相容。这种不混溶发生在有序的液体中，DNA被规则的扭曲紧密地分层，这种情况被认为可以最大限度地减少复制后的缠结，从而促进分离。(C) 2001法国生物化学和生物分子学会/ Elsevier SAS科学和医学版。
The patterns characteristic of certain liquid crystals called 'twisted nematics' or 'cholesterics' have been observed in thin sections of both dinoflagellates and bacterial chromosomes. These liquid crystals have also been obtained in vitro in concentrated DNA solutions. A large part of DNA in prokaryotic chromosomes forms such a twisted liquid crystal, whilst the remainder consists of lateral loops and is less concentrated. These semi-ordered phases could help chromosome separation to occur during and after DNA replication. We suggest that, owing to chemical differences, one of the two replicated filaments is immiscible with the rest of DNA in this chromosome. This immiscibility occurs in the context of an ordered liquid, with the DNA closely layered by a regular twist, a situation proposed to strongly minimize entangling after replication and hence to facilitate segregation. (C) 2001 Societe francaise de biochimie et biologie moleculaire / Editions scientifiques et medicales Elsevier SAS.