MersV1, PubMed, Checkpoint, bibRecord, 002308

Polydispersity of a mammalian chaperone: mass spectrometry reveals the population of oligomers in alphaB-crystallin.

Identifieur interne : 002308 ( PubMed/Checkpoint ); précédent : 002307; suivant : 002309

Polydispersity of a mammalian chaperone: mass spectrometry reveals the population of oligomers in alphaB-crystallin.

Auteurs : J Andrew Aquilina [Royaume-Uni] ; Justin L P. Benesch ; Orval A. Bateman ; Christine Slingsby ; Carol V. Robinson

Source :

Proceedings of the National Academy of Sciences of the United States of America [ 0027-8424 ] ; 2003.

RBID : pubmed:12947045

Descripteurs français

KwdFr :
- Animaux, Biopolymères (), Bovins, Chaperons moléculaires (), Cristallines (), Spectrométrie de masse.
MESH :
- Animaux, Biopolymères, Bovins, Chaperons moléculaires, Cristallines, Spectrométrie de masse.

English descriptors

KwdEn :
- Animals, Biopolymers (chemistry), Cattle, Crystallins (chemistry), Mass Spectrometry, Molecular Chaperones (chemistry).
MESH :
- chemical , chemistry : Biopolymers, Crystallins, Molecular Chaperones.
- Animals, Cattle, Mass Spectrometry.

Abstract

The quaternary structure of the polydisperse mammalian chaperone alphaB-crystallin, a member of the small heat-shock protein family, has been investigated by using electrospray mass spectrometry. The intact assemblies give rise to mass spectra that are complicated by the overlapping of charge states from the different constituent oligomers. Therefore, to determine which oligomers are formed by this protein, tandem mass spectrometry experiments were performed. The spectra reveal a distribution, primarily of oligomers containing 24-33 subunits, the relative populations of which were quantified, to reveal a dominant species being composed of 28 subunits. Additionally, low levels of oligomers as small as 10-mers and as large as 40-mers were observed. Interpretation of the tandem mass spectral data was confirmed by simulating and summing spectra arising from the major individual oligomers. The ability of mass spectrometry to quantify the relative populations of particular oligomeric states also revealed that, contrary to the dimeric associations observed in other small heat-shock proteins, there is no evidence for any stable substructures of bovine alphaB-crystallin isolated from the lens.

DOI: 10.1073/pnas.1932958100
PubMed: 12947045

Affiliations:

Royaume-Uni

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pubmed:12947045

Le document en format XML

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<front><div type="abstract" xml:lang="en">The quaternary structure of the polydisperse mammalian chaperone alphaB-crystallin, a member of the small heat-shock protein family, has been investigated by using electrospray mass spectrometry. The intact assemblies give rise to mass spectra that are complicated by the overlapping of charge states from the different constituent oligomers. Therefore, to determine which oligomers are formed by this protein, tandem mass spectrometry experiments were performed. The spectra reveal a distribution, primarily of oligomers containing 24-33 subunits, the relative populations of which were quantified, to reveal a dominant species being composed of 28 subunits. Additionally, low levels of oligomers as small as 10-mers and as large as 40-mers were observed. Interpretation of the tandem mass spectral data was confirmed by simulating and summing spectra arising from the major individual oligomers. The ability of mass spectrometry to quantify the relative populations of particular oligomeric states also revealed that, contrary to the dimeric associations observed in other small heat-shock proteins, there is no evidence for any stable substructures of bovine alphaB-crystallin isolated from the lens.</div>
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<Abstract><AbstractText>The quaternary structure of the polydisperse mammalian chaperone alphaB-crystallin, a member of the small heat-shock protein family, has been investigated by using electrospray mass spectrometry. The intact assemblies give rise to mass spectra that are complicated by the overlapping of charge states from the different constituent oligomers. Therefore, to determine which oligomers are formed by this protein, tandem mass spectrometry experiments were performed. The spectra reveal a distribution, primarily of oligomers containing 24-33 subunits, the relative populations of which were quantified, to reveal a dominant species being composed of 28 subunits. Additionally, low levels of oligomers as small as 10-mers and as large as 40-mers were observed. Interpretation of the tandem mass spectral data was confirmed by simulating and summing spectra arising from the major individual oligomers. The ability of mass spectrometry to quantify the relative populations of particular oligomeric states also revealed that, contrary to the dimeric associations observed in other small heat-shock proteins, there is no evidence for any stable substructures of bovine alphaB-crystallin isolated from the lens.</AbstractText>
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Polydispersity of a mammalian chaperone: mass spectrometry reveals the population of oligomers in alphaB-crystallin.

Polydispersity of a mammalian chaperone: mass spectrometry reveals the population of oligomers in alphaB-crystallin.

Source :

Descripteurs français

English descriptors

Abstract

Links toward previous steps (curation, corpus...)

Links to Exploration step

Le document en format XML

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Pour générer des pages wiki