Researchers from the Gerlich Group at IMBA – Institute of Molecular Biotechnology of the Austrian Academy of Sciences – discovered a molecular mechanism that confers special physical properties to chromosomes in dividing human cells to enable their faithful transport to the progeny. The team showed how a chemical modification establishes a sharp surface boundary on chromosomes, thus allowing them to resist perforation by microtubules of the spindle apparatus. The findings are published in the journal Nature.