Broccoli D, Paweletz N, Vig B K
Department of Biology, University of Nevada, Reno 89557-0015.
Chromosoma. 1989 Jun;98(1):13-22. doi: 10.1007/BF00293330.
The B1 cell line of rat cerebral endothelium origin exhibits several dicentric and multicentric chromosomes. These chromosomes, unlike multicentrics in mouse (Vig and Zinkowski 1986) do not show premature centromere separation. All centromeres deposit kinetochore proteins and appear to be functional. Even the centromeres which fail to migrate to the poles during anaphase and make side arm bridges bind to spindle microtubules. Some multicentric chromosomes show kinetochores spaced apart with intervening stretches of euchromatin while others are located adjacent to each other thus exhibiting tandem repeats and forming a "compound" kinetochore (Brinkeley et al. 1984). Also, unlike mouse multicentric chromosomes in which different pericentric regions and the centromeres replicate at different times, the rat chromosomes appear to replicate all pericentric and centric regions in a given multicentric simultaneously. The present studies indicate that centromeres in rat and mouse replicate during the last part of the S-phase and in continuation with the pericentric heterochromatin.
源自大鼠脑内皮的B1细胞系呈现出几条双着丝粒和多着丝粒染色体。这些染色体与小鼠中的多着丝粒染色体不同（Vig和Zinkowski，1986），不会出现着丝粒过早分离的情况。所有着丝粒都沉积动粒蛋白，且似乎都具有功能。即使是在后期未能迁移到两极并形成侧臂桥的着丝粒，也会与纺锤体微管结合。一些多着丝粒染色体的动粒间隔开，其间有常染色质伸展，而另一些则彼此相邻，从而呈现串联重复并形成“复合”动粒（Brinkeley等人，1984）。此外，与小鼠多着丝粒染色体不同，在小鼠多着丝粒染色体中，不同的着丝粒周围区域和着丝粒在不同时间复制，而大鼠染色体似乎在给定的多着丝粒中同时复制所有着丝粒周围和着丝粒区域。目前的研究表明，大鼠和小鼠的着丝粒在S期的最后阶段与着丝粒周围异染色质连续复制。
