In a first, UC Santa Cruz researchers and colleagues have directly observed the mechanism for protein synthesis in living cells, using “optical tweezers” to probe the physical steps of the ribosome machine as it translates genetic code into a protein molecule.

They engineered ribosomes containing messenger RNA molecules with strands of DNA attached to both ends to serve as “handles.” The DNA strands, in turn, were attached to tiny beads. Both beads were fixed by lasers, which exerted opposing forces on the translation system.