An international team of scientists, including a group led by Prof. Dr. Iva Tolić from the Ruđer Bošković Institute (IRB), recently published significant research on cell division in the prestigious journal "Cell". This study has unveiled new insights into the behavior of centromeres during cell division. Centromeres are key structures that ensure the correct distribution of chromosomes during cell division. They act as control towers, allowing chromosomes to attach properly to microtubules. Microtubules are thin, hollow tubes within the cell that help maintain cell shape, transport substances, and separate chromosomes. Using advanced technologies such as super-resolution microscopy, electron tomography, and polymer modeling, scientists have discovered that centromeres consist of two parts. Each part binds to different bundles of microtubules that assist in chromosome separation. In cancer cells, issues often arise when these parts separate too much, which can lead to errors in chromosome division and serious health problems.

International Collaboration and Recognition
Prof. Dr. Iva Tolić emphasized the importance of international collaboration in this research. This study is the result of collaboration between teams from the Netherlands, the United Kingdom, Japan, Germany, and Croatia. Special recognition was given to the cover art of the journal, created by Simona Lafirenze from the team of Prof. Geert Kops at Utrecht University. The research findings are particularly important for understanding how cancer cells form. Prof. Tolić highlighted that her team discovered that in cancer cells, such as osteosarcoma and high-grade serous ovarian cancer, residual chromosomes often get "stuck" due to improper attachment to microtubules.

New Discovery on the Evolution of Cell Division
Alongside this work, Prof. Tolić's team also participated in research on the evolution of cell division, published in the journal Nature. This study, which includes teams from Heidelberg, Lausanne, Groningen, and the IRB, reveals a connection between an organism's life cycle and the way its cells divide. Different types of marine protists have preferences for open or closed mitosis depending on their life cycle stage. This research reveals that the way animal cells divide might have existed long before animals themselves. Dr. Monika Trupinić analyzed the architecture and chirality of spindles in protists, which was crucial for understanding similarities and differences compared to spindles in different organisms.

Funding and Support
Both studies by the IRB team were funded by a European Research Council (ERC) project awarded to Prof. Dr. Iva Tolić and Prof. Dr. Nenad Pavin. This ERC Synergy grant is worth 10 million euros and includes collaboration with the Dutch Hubrecht Institute and the American MIT. Additional information on the funding for the research published in Nature: The study by Monika Trupinić was supported by the project "Career Development of Young Researchers - Training of New Doctoral Students" from the Croatian Science Foundation. Prof. Iva M. Tolić thanks the European Research Council (ERC Synergy grant, GA 855158), the Croatian Science Foundation (HRZZ project IP-2019-04-5967), and projects co-financed by the Government of the Republic of Croatia and the European Union through the European Regional Development Fund - Operational Programme Competitiveness and Cohesion: Center of Excellence QuantiXLie (KK.01.1.1.01.0004) and IPSted (KK.01.1.1.04.0057).