Biochemist Christine Dunham and her colleagues have a new paper in PNAS illuminating a long-standing puzzle concerning ribosomes, the factories inside cells that produce proteins.
Ribosomes are where the genetic code â€œhappens,â€ because they are the workshops where messenger RNA is read out and proteins are assembled piece by piece. As a postdoc, Dunham contributed to Nobel Prize-winning work determining the molecular structure of the ribosome with mentor Venki Ramakrishnan.
The puzzle is this: how messenger RNA can be faithfully and precisely translated, when the interactions that hold RNA base pairs (A-U and G-C) together are not strong enough. There is enough â€œwobbleâ€ in RNA base pairing such that transfer RNAs that donâ€™t match all three letters on the messenger RNA can still fit.