Chrysotile Block Centriole Reposition During Cytokinesis Failure In HeLa Cells

Chrysotile is a well known carcinogen which could induce malignant mesothelioma. Meanwhile, chrysotile induced binucleated cells are thought to be a potential precursor towards aneuploidy and cell transformation. However, the intrinsic mechanism of chrysotile induced binucleation is still unknown. Previous studies suggested that centriole repositioning to midbody during post-anaphase was essential for the following completion of cytokinesis. To investigate whether the centriole movements are disturbed by chrysotile treatment, we utilized live cell imaging to track centriole dynamics during chrysotile-induced binucleation in HeLa cells. For better visualization of centrioles and nuclear materials, green fluorescent protein (GFP) targeted centrin1 and red fluorescent protein (mCherry) targeted histone H2B were stably expressed in HeLa cells. Firstly, chrysotile treatment potently induced binucleation through cytoplasmic bridge regression, as expected. Meanwhile, the proportion of cells displaying aberrant centriole movement was significantly increased in chrysotile-treated cells, and centriole movement was also delayed. What is more, the aberrant centriole movements were observed to be highly correlated with cleavage furrow regression and binucleation in chrysotile-treated cells. Taken together, these results demonstrate that the disrupted centriole repositioning to midbody during the process of cytokinesis could potentially account for binucleation caused by chrysotiles.