A cell line which is temperature‐sensitive for cytokinesis

Abstract
We have isolated several cell lines which are temperature‐sensitive for growth. One of these appears to be temperature‐sensitive for cytokinesis. It was isolated from a Syrian hamster cell line by selecting cells which were not killed by 1 μg/ml cytosine arabinoside at 39° but which grew normally at 31°. It shows an increased proportion of binucleate cells when shifted to the non‐permissive temperature and time‐lapse photomicroscopy shows that a high proportion of attempted mitoses fail at 39°, apparently at the stage of cytokinesis. The cells which have failed to complete mitosis reattach to the plate and have two normal‐size nuclei but otherwise behave normally.