Does Artemis End the Hunt for the Hairpin-Opening Activity in V(D)J Recombination?

When complexed with the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), the recently discovered dsDNA break repair protein named Artemis acquires the ability to open hairpin DNA molecules in vitro. Both genetic and biochemical data point toward a physiological role for this complex as the elusive hairpin-opening activity in V(D)J recombination.