Graifer D.,Russian Academy of Sciences |
Zhigailov A.,Ajtkhozhin Institute of Molecular Biology and Biochemistry |
Ven'Yaminova A.,Russian Academy of Sciences |
Malygin A.,Russian Academy of Sciences |
And 2 more authors.
FEBS Letters | Year: 2012
The roles of 2′-OH groups in the binding of mRNA to human ribosomes were studied using site-directed cross-linking. We found that both mRNA and mDNA analogues bearing a cross-linker can modify ribosomal proteins (rps) S3e and S2e at the mRNA entry site independently on tRNA presence, but only mRNA analogues were capable of a tRNA Phe-dependent binding to human ribosomes and cross-linking to rpS26e in the mRNA binding centre. Thus, 2′-OH groups of mRNA are unimportant for binding at the entry site but they are crucial for codon-anticodon interactions at the P site, implying the existence of mRNA-ribosome contacts that do not occur in bacteria. © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Zhigailov A.V.,Ajtkhozhin Institute of Molecular Biology and Biochemistry |
Babaylova E.S.,Russian Academy of Sciences |
Polimbetova N.S.,Ajtkhozhin Institute of Molecular Biology and Biochemistry |
Graifer D.M.,Russian Academy of Sciences |
And 2 more authors.
Molecular Biology | Year: 2011
A putative implication 3′-terminal 18S rRNA segment in the cap-independent initiation of translation on plant ribosomes was studied. It was shown that 3′-terminal segment (nucleotides 1777-1811) of 18S rRNA including the last hairpin 45 was accessible for complementary interactions within 40S ribosomal subunits. Oligonucleotides complementary to this segment of rRNA, when added to wheat germ cell-free protein synthesizing system, specifically inhibited translation of uncapped reporter mRNA encoding β-glucuronidase. In the 5′-untranslated region (UTR), the reporter mRNA contained a leader sequence of potato virus Y (PVY) genomic RNA with fragments complementary to the region 1777-1811. A sequence corresponding to nucleotides 291-316 of PVY, which was complementary to most of the 3′-terminal 18S rRNA segment 1777-1808, was shown to enhance translational efficiency of the reporter mRNAs when placed into 5′-UTR. The obtained results suggest that complementary interactions between 5′-UTR of mRNA and 3′-terminal segment of 18S rRNA can take place during cap-independent translation initiation. © 2011 Pleiades Publishing, Ltd.