Publication Date:
1996-09-20
Description:
Group I self-splicing introns catalyze their own excision from precursor RNAs by way of a two-step transesterification reaction. The catalytic core of these ribozymes is formed by two structural domains. The 2.8-angstrom crystal structure of one of these, the P4-P6 domain of the Tetrahymena thermophila intron, is described. In the 160-nucleotide domain, a sharp bend allows stacked helices of the conserved core to pack alongside helices of an adjacent region. Two specific long-range interactions clamp the two halves of the domain together: a two-Mg2+-coordinated adenosine-rich corkscrew plugs into the minor groove of a helix, and a GAAA hairpin loop binds to a conserved 11-nucleotide internal loop. Metal- and ribose-mediated backbone contacts further stabilize the close side-by-side helical packing. The structure indicates the extent of RNA packing required for the function of large ribozymes, the spliceosome, and the ribosome.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cate, J H -- Gooding, A R -- Podell, E -- Zhou, K -- Golden, B L -- Kundrot, C E -- Cech, T R -- Doudna, J A -- 5T32GM08283-07/GM/NIGMS NIH HHS/ -- GM22778-21/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1996 Sep 20;273(5282):1678-85.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA. doudna@csb.yale.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8781224" target="_blank"〉PubMed〈/a〉
Keywords:
Adenine/chemistry
;
Animals
;
Base Composition
;
Base Sequence
;
Binding Sites
;
Catalysis
;
Crystallography, X-Ray
;
Hydrogen Bonding
;
*Introns
;
Magnesium/chemistry
;
Models, Molecular
;
Molecular Sequence Data
;
*Nucleic Acid Conformation
;
Phosphates/chemistry
;
Phylogeny
;
RNA Splicing
;
RNA, Catalytic/*chemistry/metabolism
;
RNA, Protozoan/*chemistry/metabolism
;
Ribose/chemistry
;
Tetrahymena thermophila/genetics
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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