Ribosome recycling factor (RRF) is required for
disassembly of the posttermination complex of the ribosome
after release of polypeptides. The crystal structure of
RRF resembles a tRNA shape, with an architecturally different
flexibility compared with tRNA, but its structure-and-function
relationships are unknown. We here found that an RRF variant
defective in ribosome binding regains the binding capacity
through 20 independent secondary changes occurring in three
topologically distinct regions of RRF. Because two of these
regions are equivalent to the tip of the anticodon stem
and the upper surface of the acceptor stem of tRNA, RRF
may interact with the ribosome in a way similar to tRNA,
spanning 30S and 50S subunits, to exert its action for
splitting the ribosome.