23 February 2022 How cells ensure proteins are cleared once their job is done Back to news Throughout the cell cycle, cells need a variety of specialized proteins to be able to divide. But how do cells ensure that all these proteins are cleared once they are no longer needed? That is one of the questions that Lenno Krenning and Stijn Sonnenveld, researchers from the group of Marvin Tanenbaum, have been focusing on. They discovered that the RNA, the genetic code for the production of these proteins, is degraded the moment the cell divides in two. The researchers published their results in eLife on 1 February 2022. Cell division forms the basis of life. It ensures that new cells are formed, so that a body can grow and damage can be repaired. Cell division is therefore essential for the development and maintenance of the tissues and organs in our bodies. When something goes wrong during cell division, diseases such as cancer can develop. Daughter cells When a cell prepares to divide, it first doubles its genetic material, the DNA. Next, the cell divides and two copies of DNA are divided equally between two new daughter cells. If the process goes well, the two cells that are formed by cell division each contain an identical copy of the DNA of the mother cell. Both daughter cells can in turn divide, creating four cells, and so on. Necessary proteins In order for the process of cell division to run smoothly, a wide variety of specialized proteins is needed at different stages of the cell cycle. These proteins not only need to be produced at the right moment during cell division, they also need to be removed once their job is done. If they remain in the cell, mistakes can occur during the next cell division. With their recent publication in eLife, Marvin Tanenbaum’s group offers new insights into how cells ensure that these proteins are cleared in time. Breakdown of genetic code The researchers discovered that the RNA – the genetic code for the production of the proteins that are important for cell division – is broken down when a cell divides in two. Without this RNA, also called messenger RNA or mRNA, no new proteins can be formed, which ensures that these proteins are quickly cleared from the cell. In addition, they discovered that a specific protein, CNOT1, is involved in the breakdown of the mRNA during cell division. Better understanding of diseases The results provide insight into the many processes that take place during cell division. Ultimately, this can contribute to our knowledge about healthy cell division, but also about what can go wrong. With this information, we can better understand the origin of diseases such as cancer. Publication Lenno Krenning*, Stijn Sonneveld* & Marvin Tanenbaum. Time-resolved single-cell sequencing identifies multiple waves of mRNA decay during the mitosis-to-G1 phase transition. eLife (2022). * equal contributions Marvin Tanenbaum is group leader at the Hubrecht Institute and Oncode researcher.