The importance of base pairing in the penultimate stem of Escherichia coli 16S rRNA for ribosomal subunit association.

AUTOR(ES)

Firpo, M A

RESUMO

The influence of base pairing in the penultimate stem of Escherichia coli 16S rRNA (defined as nt 1409-1491) on ribosome function has been addressed by the construction of mutations in this region of rRNA. Two sets of mutations were made on either side of a structurally conserved region in the penultimate stem that disrupted base pairing, while a third set of mutations replaced the wild-type sequence with other base pair combinations. The effects of these mutations were analyzed in vivo and in vitro . The mutations that disrupted base pairing caused significant increases in cell doubling times as well as a severe subunit association defect and a modest increase in frame shifting and stop codon read-through. Restoration of base pairing restored wild-type growth rates, decoding and subunit association, indicating that base pairing in this region is essential for proper ribosome function.

Documentos Relacionados

• Involvement of bases 787-795 of Escherichia coli 16S ribosomal RNA in ribosomal subunit association.
• Enhancement of translation by the downstream box does not involve base pairing of mRNA with the penultimate stem sequence of 16S rRNA
• Assembly of the Escherichia coli 30S ribosomal subunit reveals protein-dependent folding of the 16S rRNA domains.
• Interaction of Escherichia coli ribosomal protein S7 with 16S rRNA.
• Complementarity of the 16S rRNA penultimate stem with sequences downstream of the AUG destabilizes the plastid mRNAs