Results 171 to 180 of about 49,487 (207)

Modelling of the three-dimensional architecture of group I catalytic introns based on comparative sequence analysis

Journal of Molecular Biology, 1990
Alignment of the 87 available sequences of group I self-splicing introns reveals numerous instances of covariation between distant sites. Some of these covariations cannot be ascribed to historical coincidences or the known secondary structure of group I introns, and are, therefore, best explained as reflecting tertiary contacts.
F, Michel, E, Westhof
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Minimal catalytic domain of a group I self-splicing intron RNA.

Nature structural biology, 2000
The self-splicing intron ribozymes have been regarded as primitive forms of the splicing machinery for eukaryotic pre-mRNAs. The splicing activity of group I self-splicing introns is dependent on an absolutely conserved and exceptionally densely packed core region composed of two helical domains, P3-P7 and P4-P6, that are connected rigidly via base ...
Y, Ikawa, H, Shiraishi, T, Inoue
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Mutational analysis of the yeast U2 snRNA suggests a structural similarity to the catalytic core of group I introns

Cell, 1992
We have used an in vitro reconstitution system to determine the effects of a large number of mutations in the highly conserved 5' terminal domain of the yeast U2 snRNA on pre-mRNA splicing. Whereas many mutations have little or no functional consequence, base substitutions in two regions were found to have drastic effects on pre-mRNA splicing.
D S, McPheeters, J, Abelson
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A minor groove RNA triple helix within the catalytic core of a group I intron

Nature Structural Biology, 1998
Close packing of several double helical and single stranded RNA elements is required for the Tetrahymena group I ribozyme to achieve catalysis. The chemical basis of these packing interactions is largely unknown. Using nucleotide analog interference suppression (NAIS), we demonstrate that the P1 substrate helix and J8/7 single stranded segment form an ...
A A, Szewczak, L, Ortoleva-Donnelly, S P, Ryder, E, Moncoeur, S A, Strobel   +4 more
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A Tyrosyl-tRNA Synthetase Protein Induces Tertiary Folding of the Group I Intron Catalytic Core

Journal of Molecular Biology, 1996
The Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (CYT-18 protein) functions in splicing group I introns. We have used chemical-structure mapping and footprinting to investigate the interaction of the CYT-18 protein with the N. crassa mitochondrial large subunit ribosomal RNA (mt LSU) and ND1 introns, which are not detectably self-splicing in
M G, Caprara, G, Mohr, A M, Lambowitz
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RNA as a Drug Target: Recent Patents on the Catalytic Activity of Trans- Splicing Ribozymes Derived from Group I Intron RNA

Recent Patents on DNA & Gene Sequences, 2010
The importance of RNA in vital cellular events like gene expression, transport, self-splicing catalytic activity etc., renders them an alternative target for drugs and other specific RNA binding ligands. RNA targets gain significance for the fact that targeting DNA with therapeutics sooner leads to drug resistance and severe side effects by impairing ...
Irudayam Maria Johnson
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A Pneumocystis carinii Group I Intron Ribozyme That Does Not Require 2‘ OH Groups on Its 5‘ Exon Mimic for Binding to the Catalytic Core

Biochemistry, 1997
The recent increase in the population of immunocompromised patients has led to an insurgence of opportunistic human fungal infections. The lack of effective treatments against some of these pathogens makes it important to develop new therapeutic strategies. One such strategy is to target key RNAs with antisense compounds. We report the development of a
S M, Testa, C G, Haidaris, F, Gigliotti, D H, Turner   +3 more
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A Tyrosyl-tRNA Synthetase Suppresses Structural Defects in the Two Major Helical Domains of the Group I Intron Catalytic Core

Journal of Molecular Biology, 1996
The Neurospora crassa mitochondrial tyrosyl-tRNA synthetase, the CYT-18 protein, functions in splicing group I introns by promoting the formation of the catalytically active structure of the intron RNA. The group I intron catalytic core is thought to consist of two extended helical domains, one formed by coaxial stacking of P5, P4, P6, and P6a (P4-P6 ...
C A, Myers, G J, Wallweber, R, Rennard, Y, Kemel, M G, Caprara, G, Mohr, A M, Lambowitz   +6 more
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The catalytic group-I introns of the psbA gene of Chlamydomonas reinhardtii  : core structures, ORFs and evolutionary implications

Current Genetics, 1999
The sequences and predicted secondary structures of the four catalytic group-I introns in the psbA gene of Chlamydomonas reinhardtii, Cr.psbA-1-Cr.psbA-4, have been determined. Cr.psbA-1 and Cr.psbA-4 are subgroup-IA1 introns and have similar secondary structures, except at the 3' end where Cr.psbA-1 contains a large inverted-repeat domain.
S P, Holloway, N N, Deshpande, D L, Herrin   +2 more
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Deletion of P9 and stem-loop structures downstream from the catalytic core affects both 5' and 3' splicing activities in a group-I intron

Gene, 1994
The P9 stem-loop is one of the conserved structural elements found in all group-I introns. Using two deletion mutants in this region of the Tetrahymena thermophilia large ribosomal subunit intron, we show that removal of the P9 element, either alone, or together with the non-conserved downstream P9.1 and P9.2 elements, results in an intron incapable of
M G, Caprara, R B, Waring
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