Journal article
Actin Isoform-specific Conformational Differences Observed with Hydrogen/Deuterium Exchange and Mass Spectrometry
The Journal of biological chemistry, Vol.284(37), pp.25421-25430
09/11/2009
DOI: 10.1074/jbc.M109.013078
PMCID: PMC2757243
PMID: 19605362
Abstract
Actin can exist in multiple conformations necessary for normal function. Actin isoforms, although highly conserved in sequence, exhibit different biochemical properties and cellular roles. We used amide proton hydrogen/deuterium (HD) exchange detected by mass spectrometry to analyze conformational differences between
Saccharomyces cerevisiae
and muscle actins in the G and F forms to gain insight into these differences. We also utilized HD exchange to study interdomain and allosteric communication in yeast-muscle hybrid actins to better understand the conformational dynamics of actin. Areas showing differences in HD exchange between G- and F-actins are areas of intermonomer contacts, consistent with the current filament models. Our results showed greater exchange for yeast G-actin compared with muscle actin in the barbed end pivot region and areas in subdomains 1 and 2 and for F-actin in monomer-monomer contact areas. These results suggest greater flexibility of the yeast actin monomer and filament compared with muscle actin. For hybrid G-actins, the muscle-like and yeastlike parts of the molecule generally showed exchange characteristics resembling their parent actins. A few exceptions were a peptide on top of subdomain 2 and the pivot region between subdomains 1 and 3 with muscle actin-like exchange characteristics although the areas were yeastlike. These results demonstrate that there is cross-talk between subdomains 1 and 2 and the large and small domains. Hybrid F-actin data showing greater exchange compared with both yeast and muscle actins are consistent with mismatched yeast-muscle interfaces resulting in decreased stability of the hybrid filament contacts.
Details
- Title: Subtitle
- Actin Isoform-specific Conformational Differences Observed with Hydrogen/Deuterium Exchange and Mass Spectrometry
- Creators
- Ema Stokasimov - From the Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242Peter A Rubenstein - From the Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.284(37), pp.25421-25430
- DOI
- 10.1074/jbc.M109.013078
- PMID
- 19605362
- PMCID
- PMC2757243
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Publisher
- American Society for Biochemistry and Molecular Biology; 9650 Rockville Pike, Bethesda, MD 20814, U.S.A
- Grant note
- GM33689 / National Institutes of Health
- Language
- English
- Date published
- 09/11/2009
- Academic Unit
- Stead Family Department of Pediatrics; Biochemistry and Molecular Biology; Internal Medicine
- Record Identifier
- 9984025294002771
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