1z31: Difference between revisions
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'''The structure of an enzyme-activating fragment of human telomerase RNA'''<br /> | '''The structure of an enzyme-activating fragment of human telomerase RNA'''<br /> | ||
==Overview== | ==Overview== | ||
The ribonucleoprotein enzyme telomerase ensures the stability and fidelity | The ribonucleoprotein enzyme telomerase ensures the stability and fidelity of linear chromosome ends by elongating the telomeric DNA that is lost during each round of DNA replication. All telomerases contain a catalytic protein component homologous to viral reverse transcriptases (TERT) and an RNA (TR) that provides the template sequence, acts as the scaffold for ribonucleoprotein assembly, and activates the enzyme for catalysis. Vertebrate telomerase RNAs contain three highly conserved structural and functional domains: the template domain, the "CR4-CR5" or "activation" domain essential for activation of the enzymatic activity, and a 3'-terminal "box H/ACA"-homology domain responsible for ribonucleprotein assembly and maturation. Here we report the NMR structure of a functionally essential RNA structural element derived from the human telomerase RNA CR4-CR5 domain. This RNA, referred to as hTR J6, forms a stable hairpin interrupted by a single nucleotide bulge and an asymmetric internal loop. Previous work on telomerase has shown that deletion of the hTR J6 asymmetric internal loop results in an RNA incapable of binding the enzymatic protein component of the RNP and therefore an inactive RNP without telomerase activity. We demonstrate here that the J6 internal loop introduces a twist in the RNA structure that may position the entire domain into the catalytic site of the enzyme. | ||
==About this Structure== | ==About this Structure== | ||
1Z31 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http:// | 1Z31 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Z31 OCA]. | ||
==Reference== | ==Reference== | ||
The structure of an enzyme-activating fragment of human telomerase RNA., Leeper TC, Varani G, RNA. 2005 Apr;11(4):394-403. Epub 2005 Feb 9. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15703438 15703438] | The structure of an enzyme-activating fragment of human telomerase RNA., Leeper TC, Varani G, RNA. 2005 Apr;11(4):394-403. Epub 2005 Feb 9. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15703438 15703438] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Leeper, T | [[Category: Leeper, T C.]] | ||
[[Category: Varani, G.]] | [[Category: Varani, G.]] | ||
[[Category: asymmetric internal bulge]] | [[Category: asymmetric internal bulge]] | ||
| Line 18: | Line 18: | ||
[[Category: telomerase protein binding site]] | [[Category: telomerase protein binding site]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:11:39 2008'' | ||
Revision as of 17:11, 21 February 2008
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The structure of an enzyme-activating fragment of human telomerase RNA
OverviewOverview
The ribonucleoprotein enzyme telomerase ensures the stability and fidelity of linear chromosome ends by elongating the telomeric DNA that is lost during each round of DNA replication. All telomerases contain a catalytic protein component homologous to viral reverse transcriptases (TERT) and an RNA (TR) that provides the template sequence, acts as the scaffold for ribonucleoprotein assembly, and activates the enzyme for catalysis. Vertebrate telomerase RNAs contain three highly conserved structural and functional domains: the template domain, the "CR4-CR5" or "activation" domain essential for activation of the enzymatic activity, and a 3'-terminal "box H/ACA"-homology domain responsible for ribonucleprotein assembly and maturation. Here we report the NMR structure of a functionally essential RNA structural element derived from the human telomerase RNA CR4-CR5 domain. This RNA, referred to as hTR J6, forms a stable hairpin interrupted by a single nucleotide bulge and an asymmetric internal loop. Previous work on telomerase has shown that deletion of the hTR J6 asymmetric internal loop results in an RNA incapable of binding the enzymatic protein component of the RNP and therefore an inactive RNP without telomerase activity. We demonstrate here that the J6 internal loop introduces a twist in the RNA structure that may position the entire domain into the catalytic site of the enzyme.
About this StructureAbout this Structure
1Z31 is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
ReferenceReference
The structure of an enzyme-activating fragment of human telomerase RNA., Leeper TC, Varani G, RNA. 2005 Apr;11(4):394-403. Epub 2005 Feb 9. PMID:15703438
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