On the origin of crossover interference: A chromosome oscillatory movement (COM) model.
On the origin of crossover interference: A chromosome oscillatory movement (COM) model.
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DOI：
10.1186/1755-8166-4-10
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发表时间：
2011-04-08
影响因子：
1.3
通讯作者：
Hultén MA
中科院分区：
文献类型：
--
作者：
Hultén MA
自从首次发现起源于减数分裂Ⅰ前期的同源亲本染色体之间的交换不是随机放置以来，已经过去了将近世纪。事实上，交换的数量和分布受到严格调节，交换/交叉形成在沿着个体染色体长度的最佳位置，促进第一次减数分裂时染色体的规则分离。尽管许多研究解决这个问题，基本机制（S）的现象称为交叉/交叉干扰仍然是未知的，这构成了一个突出的生物学之谜。交叉/交叉干扰的染色体振荡运动（COM）模型意味着，在减数分裂I的前期，端粒的振荡运动（附着在核膜上）和动粒（在着丝粒内）沿着染色体对的长度产生沿着波（二价体），以致─通过在由此产生的波的波节区域处诱导的亲本同源物的接近，促进了重叠和交叉的形成。该模型充分解释了交换/交叉干扰的显著特征，其中（1）每个二价体通常至少有一个交换/交叉，（2）数目与二价体长度相关，（3）位置取决于每个二价体的数目，（4）在着丝粒上的干扰距离平均比沿着染色体臂的干扰距离长，（5）染色体结构重排的携带者有明显变化。具有正常核型的人和小鼠以及结构染色体重排携带者中的交叉/交叉频率分布是COM模型中预期的。正在进行进一步的研究，以分析该模型的机械/数学方面的交叉/交叉干扰的起源，使用在减数分裂I前期阶段的同源染色体的串复制品。在这类实验中变化的参数将包括：（1）有丝分裂核型，即所涉及染色体的排列长度和着丝粒指数，（2）特定的二价/多价长度和柔性，取决于该结构在细胞核内的定位方式和相应性母细胞核的大小，（3）端粒和动粒振荡运动的频率特性。
It is now nearly a century since it was first discovered that crossovers between homologous parental chromosomes, originating at the Prophase stage of Meiosis I, are not randomly placed. In fact, the number and distribution of crossovers are strictly regulated with crossovers/chiasmata formed in optimal positions along the length of individual chromosomes, facilitating regular chromosome segregation at the first meiotic division. In spite of much research addressing this question, the underlying mechanism(s) for the phenomenon called crossover/chiasma interference is/are still unknown; and this constitutes an outstanding biological enigma. The Chromosome Oscillatory Movement (COM) model for crossover/chiasma interference implies that, during Prophase of Meiosis I, oscillatory movements of the telomeres (attached to the nuclear membrane) and the kinetochores (within the centromeres) create waves along the length of chromosome pairs (bivalents) so that crossing-over and chiasma formation is facilitated by the proximity of parental homologs induced at the nodal regions of the waves thus created. This model adequately explains the salient features of crossover/chiasma interference, where (1) there is normally at least one crossover/chiasma per bivalent, (2) the number is correlated to bivalent length, (3) the positions are dependent on the number per bivalent, (4) interference distances are on average longer over the centromere than along chromosome arms, and (5) there are significant changes in carriers of structural chromosome rearrangements. The crossover/chiasma frequency distribution in humans and mice with normal karyotypes as well as in carriers of structural chromosome rearrangements are those expected on the COM model. Further studies are underway to analyze mechanical/mathematical aspects of this model for the origin of crossover/chiasma interference, using string replicas of the homologous chromosomes at the Prophase stage of Meiosis I. The parameters to vary in this type of experiment will include: (1) the mitotic karyotype, i.e. ranked length and centromere index of the chromosomes involved, (2) the specific bivalent/multivalent length and flexibility, dependent on the way this structure is positioned within the nucleus and the size of the respective meiocyte nuclei, (3) the frequency characteristics of the oscillatory movements at respectively the telomeres and the kinetochores.
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影响因子：
4.5
作者：
Cheng EY;Hunt PA;Naluai-Cecchini TA;Fligner CL;Fujimoto VY;Pasternack TL;Schwartz JM;Steinauer JE;Woodruff TJ;Cherry SM;Hansen TA;Vallente RU;Broman KW;Hassold TJ
通讯作者：
Hassold TJ
影响因子：
2.6
作者：
Basheva, E. A.;Bidau, C. J.;Borodin, P. M.
通讯作者：
Borodin, P. M.
影响因子：
2.4
作者：
Borodin, P. M.;Basheva, E. A.;Zhelezova, A. I.
通讯作者：
Zhelezova, A. I.
影响因子：
6.1
作者：
Codina-Pascual, M;Oliver-Bonet, M;Benet, J
通讯作者：
Benet, J
影响因子：
64.5
作者：
Conrad, Michael N.;Lee, Chih-Ying;Dresser, Michael E.
通讯作者：
Dresser, Michael E.