Abstract:
:Elucidation of the molecular details of the cyclic actomyosin interaction requires the ability to examine structural changes at specific sites in the actin-binding interface of myosin. To study these changes dynamically, we have expressed two mutants of a truncated fragment of chicken gizzard smooth muscle myosin, which includes the motor domain and essential light chain (MDE). These mutants were engineered to contain a single tryptophan at (Trp-546) or near (Trp-625) the putative actin-binding interface. Both 546- and 625-MDE exhibited actin-activated ATPase and actin-binding activities similar to wild-type MDE. Fluorescence emission spectra and acrylamide quenching of 546- and 625-MDE suggest that Trp-546 is nearly fully exposed to solvent and Trp-625 is less than 50% exposed in the presence and absence of ATP, in good agreement with the available crystal structure data. The spectrum of 625-MDE bound to actin was quite similar to the unbound spectrum indicating that, although Trp-625 is located near the 50/20-kDa loop and the 50-kDa cleft of myosin, its conformation does not change upon actin binding. However, a 10-nm blue shift in the peak emission wavelength of 546-MDE observed in the presence of actin indicates that Trp-546, located in the A-site of the lower 50-kDa subdomain of myosin, exists in a more buried environment and may directly interact with actin in the rigor acto-S1 complex. This change in the spectrum of Trp-546 constitutes direct evidence for a specific molecular interaction between residues in the A-site of myosin and actin.
journal_name
Proc Natl Acad Sci U S Aauthors
Yengo CM,Fagnant PM,Chrin L,Rovner AS,Berger CLdoi
10.1073/pnas.95.22.12944subject
Has Abstractpub_date
1998-10-27 00:00:00pages
12944-9issue
22eissn
0027-8424issn
1091-6490journal_volume
95pub_type
杂志文章abstract::We have isolated from vaccinia virus cores an enzyme, 5'-phosphate-polyribonucleotide kinase, that in the presence of ATP and Mg2+ catalyzes the conversion of 5'-phosphate and 5'-diphosphate termini of RNA to the 5'-triphosphate species. With the exception of dATP, other nucleoside triphosphates were inactive as phosp...
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.75.10.4793
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abstract::Pre-mRNA splicing requires the function of a number of RNA-dependent ATPases/helicases, yet no three-dimensional structure of any spliceosomal ATPases/helicases is known. The highly conserved DECD-box protein UAP56/Sub2 is an essential splicing factor that is also important for mRNA export. The expected ATPase/helicas...
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:2004-12-21 00:00:00
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doi:10.1073/pnas.1219937110
更新日期:2013-02-12 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
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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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abstract::Inbred Lewis (LEW/N) female rats develop an arthritis in response to group A streptococcal cell wall peptidoglycan polysaccharide (SCW), which mimics human rheumatoid arthritis. Histocompatible Fischer (F344/N) rats do not develop arthritis in response to the same SCW stimulus. To evaluate this difference in inflammat...
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.86.7.2374
更新日期:1989-04-01 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
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更新日期:2016-08-02 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.92.25.11741
更新日期:1995-12-05 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
doi:10.1073/pnas.76.8.3824
更新日期:1979-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,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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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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更新日期:1979-10-01 00:00:00
abstract::The rabbit kappa light chain gene family is characterized by the presence of two constant region (C kappa) genes; the C kappa 1 gene encodes the constant region of the principal rabbit immunoglobulin light chain, the C kappa 2 gene being not or very poorly expressed in domestic rabbits. There exist four major K1 allel...
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
doi:10.1073/pnas.76.7.3111
更新日期:1979-07-01 00:00:00
abstract::It has recently been recognized that human serum contains a protein that specifically binds human growth hormone (hGH). This protein has the same restricted specificity for hGH as the membrane-bound GH receptor. To determine whether the GH-binding protein is a derivative of, or otherwise related to, the GH receptor, w...
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:1987-07-01 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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更新日期:1980-04-01 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.76.5.2268
更新日期:1979-05-01 00:00:00
abstract::Ants are the world's most conspicuous and important eusocial insects and their diversity, abundance, and extreme behavioral specializations make them a model system for several disciplines within the biological sciences. Here, we report the discovery of a new ant that appears to represent the sister lineage to all ext...
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:2008-09-30 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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更新日期:2017-04-18 00:00:00
abstract::The functional architecture of mammalian visual cortex has been elucidated in impressive detail by experimental work of the past 20-25 years. The origin of many of the salient features of this architecture, however, has remained unexplained. This paper is the first of three (the others will appear in subsequent issues...
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.83.19.7508
更新日期:1986-10-01 00:00:00