Viera Alberto, Parra María Teresa, Page Jesús, Santos Juan Luis, Rufas Julio S, Suja José A
Unidad de Biología Celular, Departamento de Biología, Edificio de Ciencias Biológicas, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
Chromosome Res. 2003;11(8):797-807. doi: 10.1023/b:chro.0000005781.71466.da.
Telomeric DNA repeats as well as different specific proteins such as TRF1 and Rap1 associate in functional telomere complexes found at chromosome ends. Using spreading techniques, the presence of TRF1 and Rap1 has been reported at mammalian meiotic telomeres during prophase I. In the present study, we have analysed, by fluorescence in-situ hybridization and immunofluorescence, the appearance and location of telomere complexes during both male mouse meiotic divisions. Additionally, we have studied their relationship with different centromere/kinetochore proteins and the synaptonemal complex protein SCP3. Our results show that telomere complexes are not located at condensed meiotic chromosome tips. Therefore, a change in chromosome structure may occur from pachytene up to metaphase I involving the dynamic relocation of telomere complexes in condensed chromosomes. Moreover, we have found that proximal telomere complexes are relocated internally to kinetochores from metaphase I up to anaphase II. We discuss the functional significance of the location of telomere complexes into internal domains of condensed meiotic chromosomes.
端粒DNA重复序列以及不同的特定蛋白质，如TRF1和Rap1，会在染色体末端的功能性端粒复合体中结合。运用铺展技术，有报道称在减数分裂前期I的哺乳动物减数分裂端粒处存在TRF1和Rap1。在本研究中，我们通过荧光原位杂交和免疫荧光分析了雄性小鼠减数分裂过程中端粒复合体的出现和位置。此外，我们研究了它们与不同着丝粒/动粒蛋白以及联会复合体蛋白SCP3的关系。我们的结果表明，端粒复合体并不位于浓缩的减数分裂染色体末端。因此，从粗线期到中期I，染色体结构可能会发生变化，这涉及到端粒复合体在浓缩染色体中的动态重新定位。此外，我们发现近端端粒复合体从中期I到后期II会在动粒内部重新定位。我们讨论了端粒复合体定位到浓缩减数分裂染色体内部区域的功能意义。
