Research article

Regulation of cell cycle by the anaphase spindle midzone

Maki Murata-Hori^1,2 , Greenfield Sluder³ and Yu-li Wang¹

¹Department of Physiology, University of Massachusetts Medical School, 377 Plantation St., Worcester, Massachusetts, 01605, USA

²Mammalian Cell Biology Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, 117604, Singapore

³Department of Cell Biology, University of Massachusetts Medical School, 377 Plantation St., Worcester, Massachusetts, 01605, USA

author email corresponding author email

BMC Cell Biology 2004, 5:49doi:10.1186/1471-2121-5-49

Published:	23 December 2004

Abstract

Background

A number of proteins accumulate in the spindle midzone and midbody of dividing animal cells. Besides proteins essential for cytokinesis, there are also components essential for interphase functions, suggesting that the spindle midzone and/or midbody may play a role in regulating the following cell cycle.

Results

We microsurgically severed NRK epithelial cells during anaphase or telophase, such that the spindle midzone/midbody was associated with only one of the daughter cells. Time-lapse recording of cells severed during early anaphase indicated that the cell with midzone underwent cytokinesis-like cortical contractions and progressed normally through the interphase, whereas the cell without midzone showed no cortical contraction and an arrest or substantial delay in the progression of interphase. Similar microsurgery during telophase showed a normal progression of interphase for both daughter cells with or without the midbody. Microsurgery of anaphase cells treated with cytochalasin D or nocodazole indicated that interphase progression was independent of cortical ingression but dependent on microtubules.

Conclusions

We conclude that the mitotic spindle is involved in not only the separation of chromosomes but also the regulation of cell cycle. The process may involve activation of components in the spindle midzone that are required for the cell cycle, and/or degradation of components that are required for cytokinesis but may interfere with the cell cycle.