Begg D A, Ellis G W
J Cell Biol. 1979 Aug;82(2):542-54. doi: 10.1083/jcb.82.2.542.
The degree of mechanical coupling of chromosomes to the spindles of Nephrotoma and Trimeratropis primary spermatocytes varies with the stage of meiosis and the birefringent retardation of the chromosomal fibers. In early prometaphase, before birefringent chromosomal fibers have formed, a bivalent can be displaced toward a spindle pole by a single, continuous pull with a microneedle. Resistance to poleward displacement increases with increased development of the chromosomal fibers, reaching a maximum at metaphase. At this stage kinetochores cannot be displaced greater than 1 micrometer toward either spindle pole, even by a force which is sufficient to displace the entire spindle within the cell. The abolition of birefringence with either colcemid or vinblastine results in the loss of chromosome-spindle attachment. In the absence of birefringent fibers a chromosome can be displaced anywhere within the cell. The photochemical inactivation of colcemid by irradiation with 366-nm light results in the reformation of birefringent chromosomal fibers and the concomitant re-establishment of chromosome attachment to the spindle. These results support the hypothesis that the birefringent chromosomal fibers anchor the chromosomes to the spindle and transmit the force for anaphase chromosome movement.
肾大蚊和三点盲蝽初级精母细胞中染色体与纺锤体的机械偶联程度随减数分裂阶段和染色体纤维的双折射延迟而变化。在早前期，在双折射染色体纤维形成之前，一个二价体可以通过用微针单次连续牵拉而向纺锤体极移动。随着染色体纤维发育程度的增加，向极移动的阻力增大，在中期达到最大值。在这个阶段，即使是足以使整个纺锤体在细胞内移动的力，着丝粒也不能向任何一个纺锤体极移动超过1微米。用秋水仙酰胺或长春花碱消除双折射会导致染色体与纺锤体附着的丧失。在没有双折射纤维的情况下，染色体可以在细胞内的任何位置移动。用366纳米光照射使秋水仙酰胺发生光化学失活，会导致双折射染色体纤维的重新形成以及染色体与纺锤体附着的同时重新建立。这些结果支持了这样的假说，即双折射染色体纤维将染色体锚定在纺锤体上，并传递后期染色体移动的力。
