Abstract: We have examined the rates of chromosome and pole motion during anaphase in HeLa cells using differential interference contrast and polarization optics. In early anaphase both chromosomes and poles move apart. When the chromosomes are separated by a distance about equal to the metaphase spindle length, both chromosomes and poles slow but continue to move at a reduced rate. Throughout anaphase, the chromosomes move faster than the poles, so the chromosome-to-pole distance decreases. Treatment of the cells with about 5 × 10−8 M colchicine up to 45 min before observation tends to block normal formation of metaphase spindles, but more than half of the cells in metaphase go on through anaphase. In these cells, both chromosome and pole motions are essentially normal until the chromosomes are separated by a distance equal to the length of the metaphase spindle. After that time, chromosome motion is supressed and the poles move slowly toward one another. These data suggest that the mechanism of anaphase motion changes character when the chromosomes become spaced by the metaphase spindle length. We call anaphase before and after that time phase 1 and phase 2, respectively. The results are discussed in the light of a sliding tubule model for chromosome motion.
Publication Year: 1973
Publication Date: 1973-05-01
Language: en
Type: article
Indexed In: ['crossref', 'pubmed']
Access and Citation
Cited By Count: 39
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot