Two separate recently-published studies focusing on the structures and processes of cell division, one appearing in the journal Nature and the other in eLife, have resulted in findings that could be beneficial in understanding how cancer forms and how to better treat the disease.
In the older of the two studies, researchers from Warwick Medical School and the University of Liverpool in the UK found a new cell structure that holds the structure together – and, according to Science World Report, the structure (known as “the mesh”) was actually found by accident.
Stephen J. Royale of the Warwick Medical School Division of Biomedical Cell Biology and his colleagues were actually looking at gaps between microtubules in dividing cells, when they saw this web-like structure for the first time, linking all of the microtubules together.
Cells need to share chromosomes accurately when they divide, to prevent them from winding up with the wrong number of chromosomes and potentially causing tumors. While the mitotic spindle is responsible for sharing the chromosomes, the study authors believe that the mesh provides structural support during the chromosome-sharing process.
“Problems in cell division are common in cancer-cells frequently end up with the wrong number of chromosomes,” Emma Smith, senior science communications officer at Cancer Research UK, said in a statement. The research, she added, “provides the first glimpse of a structure that helps share out a cell’s chromosomes… [and] might be a crucial insight into why this process becomes faulty in cancer and whether drugs could be developed to stop it from happening.”
Chromosomes found to be actively involved in cell division
More recently, scientists from the University of Montreal and University College London found that chromosomes play an active role in cell division in animals – specifically during cytokinesis, the stage when the cell splits into a pair of daughter cells. While cell division takes place billions of times per day throughout an organism’s life, the mechanics are not fully understood.
Previously, scientists didn’t know that chromosomes played an active role in cytokinesis. While they knew that microtubules were involved in the process, pulling to opposite poles of the cell during the division process, experts believed the chromosomes themselves were not actively involved in the process themselves.
By conducting research using fruit fly cells, however, they found that chromosomes actually give off signals that influence the cell cortex to reinforce microtubule action. One of the signals found by the study authors involved an enzyme complex (a phosphatase called Sds22-PP1) found at the kinetochores. They also demonstrated that this pathway acts in human cells as well.
“We have been watching cells divide for more than 100 years,” said Gilles Hickson, an assistant professor at the University of Montreal’s Department of Pathology and Cell Biology, a researcher at the CHU Sainte-Justine Research Centre and one of the researchers involved in the study, “but we continue to seek to understand the molecular mechanisms involved.”
The research, he added, “is important because cell division is so central to life, and to certain diseases,” including cancer, which is typically caused by unchecked cell division. Learning more about these mechanisms could open up new potential targets for treatment in such diseases.
(Image credit: Thinkstock)