Yamanaka factors

Four gene-regulating proteins, OCT4, SOX2, KLF4 and c-MYC, that together can reprogram an adult cell into a stem cell.

• Shinya Yamanaka found them in 2006 by screening 24 candidate genes in mouse cells, and shared the 2012 Nobel Prize.
• They are transcription factors: proteins that bind DNA and switch whole programmes of genes on or off, rewiring the cell's identity.
• c-MYC is a known cancer gene, so longevity research often uses only the other three (OSK).
• The process is inefficient, typically under 1% of cells fully converting, and prolonged activation in animals causes tumours called teratomas.