Imagerie PI2

@article{,

title = {Comprehensive features of natural and in vitro selected GNRA tetraloop-binding receptors},

author = { C. Geary and S. Baudrey and L. Jaeger},

year  = {2008},

date = {2008-01-01},

journal = {Nucleic Acids Res},

volume = {36},

number = {4},

pages = {1138-52},

abstract = {Specific recognitions of GNRA tetraloops by small helical receptors are among the most widespread long-range packing interactions in large ribozymes. However, in contrast to GYRA and GAAA tetraloops, very few GNRA/receptor interactions have yet been identified to involve GGAA tetraloops in nature. A novel in vitro selection scheme based on a rigid self-assembling tectoRNA scaffold designed for isolation of intermolecular interactions with A-minor motifs has yielded new GGAA tetraloop-binding receptors with affinity in the nanomolar range. One of the selected receptors is a novel 12 nt RNA motif, (CCUGUG. AUCUGG), that recognizes GGAA tetraloop hairpin with a remarkable specificity and affinity. Its physical and chemical characteristics are comparable to those of the well-studied '11nt' GAAA tetraloop receptor motif. A second less specific motif (CCCAGCCC. GAUAGGG) binds GGRA tetraloops and appears to be related to group IC3 tetraloop receptors. Mutational, thermodynamic and comparative structural analysis suggests that natural and in vitro selected GNRA receptors can essentially be grouped in two major classes of GNRA binders. New insights about the evolution, recognition and structural modularity of GNRA and A-minor RNA-RNA interactions are proposed.},

note = {1362-4962 (Electronic) 

Journal Article 

Research Support, N.I.H., Extramural 

Research Support, U.S. Gov't, Non-P.H.S.},

keywords = {Acid, Adenine/chemistry, Analysis, Base, Conformation, Data, dimerization, directed, Evolution, KROL, Models, Molecular, Nucleic, RNA, RNA/*chemistry/classification, Sequence, Thermodynamics},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Nucleotides U28-A42 and A37 in unmodified yeast tRNA(Trp) as negative identity elements for bovine tryptophanyl-tRNA synthetase},

author = { D. Carnicelli and M. Brigotti and S. Rizzi and G. Keith and L. Montanaro and S. Sperti},

year  = {2001},

date = {2001-01-01},

journal = {FEBS Lett},

volume = {492},

number = {3},

pages = {238-41},

abstract = {Wild-type bovine and yeast tRNA(Trp) are efficiently aminoacylated by tryptophanyl-tRNA synthetase both from beef and from yeast. Upon loss of modified bases in the synthetic transcripts, mammalian tRNA(Trp) retains the double recognition by the two synthetases, while yeast tRNA(Trp) loses its substrate properties for the bovine enzyme and is recognised only by the cognate synthetase. By testing chimeric bovine-yeast transcripts with tryptophanyl-tRNA synthetase purified from beef pancreas, the nucleotides responsible for the loss of charging of the synthetic yeast transcript have been localised in the anticodon arm. A complete loss of charging akin to that observed with the yeast transcript requires substitution in the bovine backbone of G37 in the anticodon loop with yeast A37 and of C28-G42 in the anticodon stem with yeast U28-A42. Since A37 does not prevent aminoacylation of the wild-type yeast tRNA(Trp) by the beef enzyme, a negative combination apparently emerges in the synthetic transcript after unmasking of U28 by loss of pseudourydilation.},

note = {0014-5793 

Journal Article},

keywords = {Acid, Adenine/chemistry, Animals, Base, Cattle, cerevisiae/genetics, Conformation, Data, Fungal/genetics/metabolism, Gov't, Kinetics, Ligase/*metabolism, Molecular, Non-U.S., Nucleic, RNA, Saccharomyces, Sequence, Species, Specificity, Substrate, Support, Transfer, Trp/chemistry/*metabolism, Tryptophan-tRNA, Uridine/chemistry},

pubstate = {published},

tppubtype = {article}

}