Post #4864

Scientists Overturn 20 Years of Textbook Biology With Stunning Discovery About Cell Division Researchers at the Ruđer Bošković Institute (RBI) in Zagreb, Croatia, have uncovered that the protein CENP-E, once thought to function as a motor pulling chromosomes into position during cell division, actually serves a different purpose. Rather than dragging chromosomes, CENP-E stabilizes their initial connections to the cell’s internal “tracks,” ensuring they are properly aligned before being separated. In a complementary study, scientists also discovered that centromeres—small structures within cells once believed to work independently—actually guide this essential protein to help maintain accurate cell division. These findings overturn more than twenty years of established textbook knowledge and have major implications for the life sciences, as mistakes in this process are linked to cancer and genetic disorders. Every second, trillions of times over, the human body performs an extraordinary feat. A single cell prepares to divide, containing three billion DNA letters, and somehow guarantees that both daughter cells inherit precise copies of this genetic code. When that precision falters, the outcome can be devastating. Even one misplaced chromosome can disrupt development, lead to infertility, or trigger cancer. Cell division is among the most exacting processes in biology. For decades, researchers believed they understood at least one of the key components involved: CENP-E, described as a molecular motor responsible for pulling stray chromosomes to the center of the cell to ensure proper division. The explanation was tidy, convincing, and ultimately incorrect. Two new studies from RBI, published in Nature Communications and led by Dr. Kruno Vukušić and Professor Iva Tolić, have redefined that understanding and proposed new mechanisms for how CENP-E functions. Dr. Vukušić, a leading young researcher in cell biology, completed his postdoctoral work within an elite ERC Synergy team and is now preparing to form his own research group at RBI. Professor Tolić, an internationally recognized cell biologist who heads the Laboratory for Cell Biophysics at RBI, has received two ERC grants and is a member of EMBO and Academia Europaea. Together, their combined expertise revealed that CENP-E is not the system’s motor but its regulator—the crucial switch that activates at just the right time to ensure flawless coordination of chromosome movement. “CENP-E is not the engine pulling chromosomes to the center,” Vukušić says. “It is the factor that ensures they can attach properly in the first place. Without that initial stabilization, the system stalls.” Source:SciTechDaily @EverythingScience