Cooperative stacking and hydrogen bond pairing interactions of fragment peptide in cap binding protein with mRNA cap structure.
The stacking and hydrogen bonding abilities of Trp-(Gly)n-Glu (n = 0 approximately 3) for the interaction with 7-methylguanine (m7G) base were examined by fluorescence and 1H-NMR methods, and it was shown that they correlate with the distance between the Trp and Glu residues, and become most significant when both residues are separated from each other by two Gly residues (n = 2). Based on this insight, the sequence conserved between the human and yeast cap binding proteins (CBPs) was surveyed, and the sequence of Trp-Glu-Asp-Glu (No. 102-105 in human CBP) was selected as a probable site for the binding with mRNA cap structure. Thus, the stacking and hydrogen bonding abilities of Trp-Glu-Asp-Glu with m7G cap structure were examined by comparative experiments using its analogous peptides. The results showed that the fourth Glu residue is important not only for the construction of hydrogen bond pairing with m7G base but also for strengthening the stacking interaction between the Trp indole ring and m7G base. Taking account of the recognition analysis using the mutant CBP proteins by site-directed mutagenesis (Ueda, H., Iyo, H., Doi, M., Inoue, M., Ishida, T., Morioka, H., Tanaka, T., Nishikawa, S. and Uesugi, S. (1991) FEBS Lett. 280, 207-210), this cooperative interaction could be important for the recognition of mRNA cap structure.
Osaka University of Pharmaceutical Sciences, Matsubara, Japan.
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H
Ueda
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Iyo
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Doi
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Inoue
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Ishida
D000595:Amino Acid Sequence; D000818:Animals; D002846:Chromatography, Affinity; D003432:Cross-Linking Reagents; D005973:Glutamine / Q000737:chemistry; D006151:Guanosine / Q000031:analogs & derivatives / Q000737:chemistry; D006801:Humans; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D011487:Protein Conformation; D039381:RNA Cap-Binding Proteins; D012315:RNA Caps / Q000737:chemistry*; D012333:RNA, Messenger / Q000737:chemistry*; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D013050:Spectrometry, Fluorescence; D014364:Tryptophan / Q000737:chemistry
D003432:Cross-Linking Reagents; D010446:Peptide Fragments; D039381:RNA Cap-Binding Proteins; D012315:RNA Caps; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D005973:Glutamine; D006151:Guanosine; C016578:7-methylguanosine; D014364:Tryptophan