-stop signal
on mRNA read by protein release factors causes release of completed polypeptide chain
-RF1 recognizes UAA and UAG
-RF2 recognizes UAA and UGA
-RF3 binds GTP
and enhances action of RF1 and RF2
-binding of
RF1-RF3-GTP (or RF2-RF3-GTP) to ribosome causes hydrolysis of peptidyl-tRNA
-GTP is then
hydrolyzed and the release factors dissociate from ribosome