Pecinka Ales, Schubert Veit, Meister Armin, Kreth Gregor, Klatte Marco, Lysak Martin A, Fuchs Jörg, Schubert Ingo
Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, 06466 Gatersleben, Germany.
Chromosoma. 2004 Nov;113(5):258-69. doi: 10.1007/s00412-004-0316-2. Epub 2004 Oct 9.
Differential painting of all five chromosome pairs of Arabidopsis thaliana revealed for the first time the interphase chromosome arrangement in a euploid plant. Side-by-side arrangement of heterologous chromosome territories and homologous association of chromosomes 1, 3 and 5 (on average in 35-50% of nuclei) are in accordance with the random frequency predicted by computer simulations. Only the nucleolus organizing region (NOR)-bearing chromosome 2 and 4 homologs associate more often than randomly, since NORs mostly attach to a single nucleolus. Somatic pairing of homologous approximately 100 kb segments occurs less frequently than homolog association, not significantly more often than expected at random and not simultaneously along the homologs. Thus, chromosome arrangement in Arabidopsis differs from that in Drosophila (characterized by somatic pairing of homologs), in spite of similar genome size, sequence organization and chromosome number. Nevertheless, in up to 31.5% of investigated Arabidopsis nuclei allelic sequences may share positions close enough for homologous recombination.
对拟南芥所有五对染色体的差异染色首次揭示了整倍体植物间期染色体的排列情况。异源染色体区域的并排排列以及1号、3号和5号染色体的同源关联（平均在35%-50%的细胞核中）与计算机模拟预测的随机频率一致。只有携带核仁组织区（NOR）的2号和4号染色体同源物的关联频率高于随机水平，因为核仁组织区大多附着于单个核仁。同源的约100 kb片段的体细胞配对发生频率低于同源物关联，并不显著高于随机预期，且不同时发生在同源物上。因此，尽管拟南芥与果蝇的基因组大小、序列组织和染色体数目相似，但其染色体排列与果蝇不同（果蝇以同源物的体细胞配对为特征）。然而，在高达31.5%的被研究拟南芥细胞核中，等位基因序列可能处于足够近的位置以进行同源重组。
