Translation Termination and Yeast Prions (Introductory Remarks of the
Guest Editor of This Special Issue)
L. L. Kisselev
Engelhardt Institute of Molecular Biology, Russian Academy of Sciences,
ul. Vavilova 32, Moscow, 117984 Russia; fax: (095) 135-1405; E-mail:
kissel@imb.ac.ru
Received July 10, 1999
Protein biosynthesis is the final step in the transfer of genetic
information in the cell. In turn, its last step is the release of a
nascent polypeptide from the ribosome. Therefore, termination of
translation may be considered (if we do not take into account protein
post-translational modification and folding) as a final step of the
transition from genotype to phenotype through the classic
DNA--RNA--protein pathway. In a narrow sense, termination of
translation is the hydrolytic cleavage of peptidyl-tRNA into free tRNA
and completed polypeptide chain carrying all the information encoded in
the corresponding mRNA and DNA. Then the completed protein molecule is
released from the ribosome and the ribosome dissociates into its
components (subunits, factors, mRNA, tRNA, etc.). After the synthesis
is completed, the polypeptide chain is folded either cotranslationally
or by an additional specialized mechanism, depending on the nature of
the protein, organism, and other factors. This issue of
Biochemistry (Moscow) highlights from various points of
view the problem of translation termination, excluding protein folding.
Yeast termination factors with prion-like properties are also
considered.
KEY WORDS: protein biosynthesis, translation termination,
prokaryotes, eukaryotes, release factors, prions