Probing the interactions of poly(U) and tRNA(Phe) with nucleotides 1530-1542 and 1390-1417 of 16 S rRNA of Escherichia coli.
The decoding region of 16 S rRNA (nucleotides 1396-1403) is not available to complementary DNA oligomer binding in 70 S ribosomes, despite high levels of binding of these oligomers to active 30 S ribosomal subunits. While addition of poly(U) or tRNA(Phe) alone did not affect the binding of either cDNA to 30 or 70 S ribosomes, poly(U)-directed tRNA(Phe) decreased the binding of cDNA (1396-1403) oligomers by 80% to the active 30 S ribosomal subunits. But the poly(U)-directed tRNA(Phe) cannot displace a prebound cDNA in this region, nor can the cDNA displace a prebound poly(U)-directed tRNA(Phe). A cDNA to the anti-Shine-Dalgarno region (nucleotides 1534-1541) binds equally well to 30 and 70 S ribosomal particles, but the simultaneous addition of poly(U)/tRNA(Phe) and cDNA results in a 50% decrease in binding of the cDNA. In this case the poly(U)-directed tRNA(Phe) does displace the prebound cDNA, but the cDNA cannot displace a prebound poly(U)-directed tRNA(Phe). Neither cDNA oligomer inhibits the reassociation of the ribosomal subunits into 70 S particles.
Division of Biological Sciences, University of Montana, Missoula 59812.
J
J
Weller
W E
WE
Hill
D001483:Base Sequence; D002499:Centrifugation, Density Gradient; D018076:DNA, Complementary / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics*; D008024:Ligands; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis / Q000378:metabolism; D011072:Poly U / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics* / Q000378:metabolism*; D012360:RNA, Transfer, Phe / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism
D018076:DNA, Complementary; D008024:Ligands; D009838:Oligodeoxyribonucleotides; D012336:RNA, Ribosomal, 16S; D012360:RNA, Transfer, Phe; D011072:Poly U