i3S researchers discover switch that prevents errors in cell division
New research reveals a molecular mechanism that adjusts the timing of cell division to prevent genetic errors associated with cancer
An international team of scientists led by Carlos Conde, a researcher at the Institute for Research and Innovation in Health at the University of Porto (i3S), has identified a mechanism that acts as a safety switch during cell division (mitosis). This discovery, published in the prestigious journal Current Biology, reveals how this switch controls a protein that can halt the entire division process until it is certain that the chromosomes are distributed accurately. Understanding this mechanism paves the way for new therapeutic strategies that can interrupt the uncontrolled division of cells with errors, such as cancer cells.
Cell division is a high-risk event that requires precise control. “If genetic material is not distributed equally, the cells resulting from this division acquire an incorrect number of chromosomes (a condition called aneuploidy), which is a characteristic of almost all solid tumours and many developmental disorders”, explains Carlos Conde, a researcher in the ’Cell Division & Genomic Stability" group at i3S and a lecturer at the Abel Salazar Institute of Biomedical Sciences (ICBAS).
To ensure this precision, the researcher continues, “cells employ a quality control system called the "mitotic checkpoint" that acts as a brake, halting cell division until all chromosomes are perfectly attached to the cellular microtubule machinery that distributes them to the new cells being formed.” The central mystery has been to identify the mechanism that releases this brake quickly, but not prematurely. This study, Carlos Conde points out, “identifies a simple but powerful molecular switch that controls a specific enzyme, PP1, which is responsible for releasing the brake when everything is ready to be divided.”
The study also shows that when this switch is defective, errors occur in chromosome distribution and an accumulation of aneuploid cells, i.e., cells with the potential to form a tumour. “This demonstrates that fine-tuning the activity of the PP1 enzyme (the switch) is essential for the cells of an organism to divide at the right time to generate new cells free of genetic errors,” explains the i3S scientist.
“This discovery has future implications. Researchers now have a new molecular strategy to control cell division”, says Carlos Conde. This knowledge paves the way for the exploration of new therapeutic strategies, explains the researcher: “It could potentially lead to the development of drugs that selectively target this molecular switch to stop the uncontrolled division of cancer cells. It could also be important for improving the success of regenerative medicine, where precise cell growth is necessary”.