论文信息 - Binding constants in the formation of mammalian protein synthesis initiation complexes and the role of mRNA.

Binding constants in the formation of mammalian protein synthesis initiation complexes and the role of mRNA.

The findings of Parkhurst et al. (Biochemistry 33, 15168-15177:1994) that a 10-mer oligoribonucleotide containing the AUG triplet enhances the binding of the eIF-2 x Met-tRNAi complex to the 40S ribosomal subunit are questioned on the basis of a re-evaluation of their calculations. It is not possible to conclude, as they did, that addition of the AUG-containing oligonucleotide produces an exceptionally large increase (as judged by the magnitude of the coupling free energy) in the binding of the eIF-2 x Met-tRNAi complex to the 40S subunit, or that their results are more consistent with internal initiation than with the scanning initiation model.

K L Manchester

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