Abstract:
:The 33-amino-acid ankyrin motif comprises a beta-turn followed by two anti-parallel alpha-helices and a loop and tandem arrays of the motif pack in a linear fashion to produce elongated structures characterized by short-range interactions. In this article we use site-directed mutagenesis to investigate the kinetic unfolding mechanism of D34, a 426-residue, 12-ankyrin repeat fragment of the protein ankyrinR. The data are consistent with a model in which the N-terminal half of the protein unfolds first by unraveling progressively from the start of the polypeptide chain to form an intermediate; in the next step, the C-terminal half of the protein unfolds via two pathways whose transition states have either the early or the late C-terminal ankyrin repeats folded. We conclude that the two halves of the protein unfold by different mechanisms because the N-terminal moiety folds and unfolds in the context of a folded C-terminal moiety, which therefore acts as a "seed" and confers a unique directionality on the process, whereas the C-terminal moiety folds and unfolds in the context of an unfolded N-terminal moiety and therefore behaves like a single-domain ankyrin repeat protein, having a high degree of symmetry and consequently more than one unfolding pathway accessible to it.
journal_name
Proc Natl Acad Sci U S Aauthors
Werbeck ND,Rowling PJ,Chellamuthu VR,Itzhaki LSdoi
10.1073/pnas.0705300105subject
Has Abstractpub_date
2008-07-22 00:00:00pages
9982-7issue
29eissn
0027-8424issn
1091-6490pii
0705300105journal_volume
105pub_type
杂志文章abstract::Bacteriophage T3-induced RNA polymerase, upon copying its specific template, native T3 DNA, initiates RNA chains only with GTP. Denaturation of the DNA results in loss of template specificity for the polymerase. With denatured T3 DNA as template, T3 polymerase initiates RNA chains with both ATP and GTP, and the averag...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.69.1.55
更新日期:1972-01-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.2.787
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.24.11388
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2001-02-27 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2018-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1600899113
更新日期:2016-06-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.13.6939
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1516536112
更新日期:2015-11-10 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.92.26.12357
更新日期:1995-12-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.5.1992
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1984-01-01 00:00:00
abstract::The translocation from chromosome 8 to chromosome 21, t(8;21), associated with acute myeloid leukemia results in production of an AML1/MTG8(ETO) fusion transcript. The product of the AML1 gene contains an evolutionarily conserved 128-amino acid region referred to as the "Runt domain," which is necessary for binding to...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1994-11-22 00:00:00
abstract::Direct measurements of the intracellular level of lambda repressor have been made by a DNA-filter assay and a radioimmune assay. Transcription of cI, the structural gene for repressor, appears to initiate at two different promoters, prm and pre. Promoter pre is activated during the establishment of lysogeny by the act...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1971-09-01 00:00:00
abstract::Efforts to delineate the advent of many enzymes essential to protein translation are often limited by the fact that the modern genetic code evolved before divergence of the tree of life. Glutaminyl-tRNA synthetase (GlnRS) is one noteworthy exception to the universality of the translation apparatus. In eukaryotes and s...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2003-09-30 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1983-09-01 00:00:00
abstract::Analysis of the mRNA capping apparatus of the malaria parasite Plasmodium falciparum illuminates an evolutionary connection to fungi rather than metazoans. We show that P. falciparum encodes separate RNA guanylyltransferase (Pgt1) and RNA triphosphatase (Prt1) enzymes and that the triphosphatase component is a member ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.061636198
更新日期:2001-03-13 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1998-02-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.6.1614
更新日期:1985-03-01 00:00:00
abstract::A panel of 26 mouse-human somatic cell hybrids containing different human chromosome complements was analyzed with a cloned human pepsinogen cDNA probe to determine the chromosomal location and the number of genes encoding these proteins. A complex containing variable numbers of pepsinogen genes was localized to the c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.18.6240
更新日期:1985-09-01 00:00:00