2009 Science News of the Year: Genes & Cells

Cancer-fighting roles
Scientists have discovered a new role in cancer protection for an already well-known tumor suppressor protein. The protein, called p53, protects cells from becoming cancerous by sensing stress and either shutting down cell division or triggering cell death. Researchers at the University of Tokyo and colleagues have discovered that p53 also plays a role in slicing stretches of RNA into regulatory molecules called microRNAs (SN: 8/15/09, p.