The secondary structure of mRNAs from Escherichia coli: its possible role in increasing the accuracy of translation.
AUTOR(ES)
Shpaer, E G
RESUMO
A secondary structure model was proposed for mRNAs during translation (in a polysome) where the secondary structure is described by a set of small unbranched hairpins. Computer simulation experiments reveal that the number of hairpins is much greater (P less than 10(-6) in highly expressed mRNAs from E. coli as compared with the random sequences coding for the same amino acid sequence, i.e. certain synonymous codons are used in definite mRNA positions to increase the number of hairpins. No constraints on the amino acid sequence, which would affect the secondary structure of mRNAs, were found. The codons UGU, UGC (Cys), GCC (Ala), ACA, ACG (Thr), CCU, CCC (Pro), etc. translated by minor tRNAs were found to occur significantly more frequently in the position 5' to the hairpins than the other codons translated by major tRNAs (P less than 5.10(-6). This correlation leads to the hypothesis that the process of hairpin unfolding can increase the time of translocation from the A to P ribosome site of the codon 5' to the hairpin, thus decreasing the probability of translational error (the latter would likely occur more frequently in the codons translated by minor tRNAs).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=340990Documentos Relacionados
- Removal of 5'-terminal m7G from eukaryotic mRNAs by potato nucleotide pyrophosphatase and its effect on translation.
- Bacteriophage f1 infection of Escherichia coli: identification and possible processing of f1-specific mRNAs in vivo.
- Translation inhibitors stabilize Escherichia coli mRNAs independently of ribosome protection
- Circumstances and mechanisms of inhibition of translation by secondary structure in eucaryotic mRNAs.
- Poly(riboadenylic acid) preferentially inhibits in vitro translation of cellular mRNAs compared with vaccinia virus mRNAs: possible role in vaccinia virus cytopathology.