A research team from Cold Spring Harbor Laboratory last week published new details about human Argonaute proteins, further revealing why only one of these four proteins is able to slice target messenger RNA during RNA interference.

Small RNA binding to an Argonaute is a defining step in the RNAi process given that the proteins are critical components of the RNA-induced silencing complex. In humans, however, only Argonaute2 slices despite its structural similarity to the other three Argonaute proteins.