A translational enhancer derived from tobacco mosaic virus is functionally equivalent to a Shine-Dalgarno sequence.

AUTOR(ES)

Gallie, D R

RESUMO

When present at the 5' end of mRNAs, the untranslated leader sequence (omega) of tobacco mosaic virus RNA significantly enhances translation in eukaryotes and prokaryotes. We have tested a deletion derivative of the omega sequence, omega delta 3, for its enhancing ability on gene constructs in which the ribosomal binding site was either present or deleted, in several Gram-negative bacterial species including Escherichia coli, Agrobacterium tumefaciens, Xanthomonas campestris pv. vitians, Erwinia amylovora, and Salmonella typhimurium. In vivo production of chloramphenicol acetyltransferase from a gene construct lacking its native ribosomal binding site was enhanced 40- to 120-fold by the presence of omega delta 3. Similar levels of enhancement (30- to 240-fold) were observed when the gene encoding beta-glucuronidase was tested. With a chloramphenicol acetyltransferase construct containing a ribosomal binding site, enhancement was markedly less, between 1- and 3.8-fold. Omega delta 3 appeared to enhance translation independent of its position upstream of the AUG codon used for initiation.

Documentos Relacionados

• Separation of mutant and wild-type ribosomes based on differences in their anti Shine-Dalgarno sequence.
• An efficient Shine-Dalgarno sequence but not translation is necessary for lacZ mRNA stability in Escherichia coli.
• Multiple elements required for translation of plastid atpB mRNA lacking the Shine-Dalgarno sequence
• Identification of the Shine-Dalgarno sequence required for expression and translational control of the pyrC gene in Escherichia coli K-12.
• Bacteriophage T4 regA protein binds to the Shine-Dalgarno region of gene 44 mRNA.